Preventive healthcare, or prophylaxis, consists of measures taken for disease prevention. Disease and disability are affected by environmental factors, genetic predisposition, disease agents, and lifestyle choices and are dynamic processes which begin before individuals realize they are affected. Disease prevention relies on anticipatory actions that can be categorized as primal, primary, secondary, and tertiary prevention.
Each year, millions of people die of preventable deaths. A 2004 study showed that about half of all deaths in the United States in 2000 were due to preventable behaviors and exposures. Leading causes included cardiovascular disease, chronic respiratory disease, unintentional injuries, diabetes, and certain infectious diseases. This same study estimates that 400,000 people die each year in the United States due to poor diet and a sedentary lifestyle. According to estimates made by the World Health Organization (WHO), about 55 million people died worldwide in 2011, two thirds of this group from non-communicable diseases, including cancer, diabetes, and chronic cardiovascular and lung diseases. This is an increase from the year 2000, during which 60% of deaths were attributed to these diseases. Preventive healthcare is especially important given the worldwide rise in prevalence of chronic diseases and deaths from these diseases.
There are many methods for prevention of disease. One of them is prevention of teenage smoking through information giving. It is recommended that adults and children aim to visit their doctor for regular check-ups, even if they feel healthy, to perform disease screening, identify risk factors for disease, discuss tips for a healthy and balanced lifestyle, stay up to date with immunizations and boosters, and maintain a good relationship with a healthcare provider. Some common disease screenings include checking for hypertension (high blood pressure), hyperglycemia (high blood sugar, a risk factor for diabetes mellitus), hypercholesterolemia (high blood cholesterol), screening for colon cancer, depression, HIV and other common types of sexually transmitted disease such as chlamydia, syphilis, and gonorrhea, mammography (to screen for breast cancer), colorectal cancer screening, a Pap test (to check for cervical cancer), and screening for osteoporosis. Genetic testing can also be performed to screen for mutations that cause genetic disorders or predisposition to certain diseases such as breast or ovarian cancer. However, these measures are not affordable for every individual and the cost effectiveness of preventive healthcare is still a topic of debate.
Levels of preventionEdit
Preventive healthcare strategies are described as taking place at the primal, primary, secondary, and tertiary prevention levels. Although advocated as preventive medicine in the early twentieth century by Sara Josephine Baker, in the 1940s, Hugh R. Leavell and E. Gurney Clark coined the term primary prevention. They worked at the Harvard and Columbia University Schools of Public Health, respectively, and later expanded the levels to include secondary and tertiary prevention. Goldston (1987) notes that these levels might be better described as "prevention, treatment, and rehabilitation", although the terms primary, secondary, and tertiary prevention are still in use today. The concept of primal prevention has been created much more recently, in relation to the new developments in molecular biology over the last fifty years, more particularly in epigenetics, which point to the paramount importance of environmental conditions - both physical and affective - on the organism during its fetal and newborn life (or so-called primal period of life).
|Primal and primordial prevention||Any measure aimed at helping future parents provide their upcoming child with adequate attention, as well as secure physical and affective environments from conception to first birthday.|
|Primary prevention||Methods to avoid occurrence of disease either through eliminating disease agents or increasing resistance to disease. Examples include immunization against disease, maintaining a healthy diet and exercise regimen, and avoiding smoking.|
|Secondary prevention||Methods to detect and address an existing disease prior to the appearance of symptoms. Examples include treatment of hypertension (a risk factor for many cardiovascular diseases), and cancer screenings.|
|Tertiary prevention||Methods to reduce the harm of symptomatic disease, such as disability or death, through rehabilitation and treatment. Examples include surgical procedures that halt the spread or progression of disease.|
|Quaternary prevention||Methods to mitigate or avoid results of unnecessary or excessive interventions in the health system|
Primal and primordial preventionEdit
Primal prevention has recently been propounded as a separate category of "health promotion". This health promotion par excellence is based on the 'new knowledge' in molecular biology, in particular on epigenetic knowledge, which points to how much affective - as well as physical - environment during fetal and newborn life may determine each and every aspect of adult health. This new way of promoting health consists mainly in providing future parents with pertinent, unbiased information on primal health and supporting them during their child's primal period of life (i.e., "from conception to first anniversary" according to definition by the Primal Health Research Centre, London). This includes adequate parental leave - ideally for both parents - with kin caregiving and financial help where needed.
Primary prevention consists of traditional "health promotion" and "specific protection." Health promotion activities are current, non-clinical life choices. For example, eating nutritious meals and exercising daily, that both prevent disease and create a sense of overall well-being. Preventing disease and creating overall well-being, prolongs our life expectancy. Health-promotional activities do not target a specific disease or condition but rather promote health and well-being on a very general level. On the other hand, specific protection targets a type or group of diseases and complements the goals of health promotion.
Food is very much the most basic tool in preventive health care. The 2011 National Health Interview Survey performed by the Centers for Disease Control was the first national survey to include questions about ability to pay for food. Difficulty with paying for food, medicine, or both is a problem facing 1 out of 3 Americans. If better food options were available through food banks, soup kitchens, and other resources for low-income people, obesity and the chronic conditions that come along with it would be better controlled. A "food desert" is an area with restricted access to healthy foods due to a lack of supermarkets within a reasonable distance. These are often low-income neighborhoods with the majority of residents lacking transportation. There have been several grassroots movements in the past 20 years to encourage urban gardening, such as the GreenThumb organization in New York City. Urban gardening uses vacant lots to grow food for a neighborhood and is cultivated by the local residents. Mobile fresh markets are another resource for residents in a "food desert", which are specially outfitted buses bringing affordable fresh fruits and vegetables to low-income neighborhoods. These programs often hold educational events as well such as cooking and nutrition guidance. Programs such as these are helping to provide healthy, affordable foods to people who need them.
Scientific advancements in genetics have significantly contributed to the knowledge of hereditary diseases and have facilitated great progress in specific protective measures in individuals who are carriers of a disease gene or have an increased predisposition to a specific disease. Genetic testing has allowed physicians to make quicker and more accurate diagnoses and has allowed for tailored treatments or personalized medicine. Similarly, specific protective measures such as water purification, sewage treatment, and the development of personal hygienic routines (such as regular hand-washing) became mainstream upon the discovery of infectious disease agents such as bacteria. These discoveries have been instrumental in decreasing the rates of communicable diseases that are often spread in unsanitary conditions. Preventing sexually transmitted infections is another form of primary prevention.
Secondary prevention deals with latent diseases and attempts to prevent an asymptomatic disease from progressing to symptomatic disease. Certain diseases can be classified as primary or secondary. This depends on definitions of what constitutes a disease, though, in general, primary prevention addresses the root cause of a disease or injury whereas secondary prevention aims to detect and treat a disease early on. Secondary prevention consists of "early diagnosis and prompt treatment" to contain the disease and prevent its spread to other individuals, and "disability limitation" to prevent potential future complications and disabilities from the disease. For example, early diagnosis and prompt treatment for a syphilis patient would include a course of antibiotics to destroy the pathogen and screening and treatment of any infants born to syphilitic mothers. Disability limitation for syphilitic patients includes continued check-ups on the heart, cerebrospinal fluid, and central nervous system of patients to curb any damaging effects such as blindness or paralysis.
Finally, tertiary prevention attempts to reduce the damage caused by symptomatic disease by focusing on mental, physical, and social rehabilitation. Unlike secondary prevention, which aims to prevent disability, the objective of tertiary prevention is to maximize the remaining capabilities and functions of an already disabled patient. Goals of tertiary prevention include: preventing pain and damage, halting progression and complications from disease, and restoring the health and functions of the individuals affected by disease. For syphilitic patients, rehabilitation includes measures to prevent complete disability from the disease, such as implementing work-place adjustments for the blind and paralyzed or providing counseling to restore normal daily functions to the greatest extent possible.
Leading causes of preventable deathEdit
The leading cause of death in the United States was tobacco. However, poor diet and lack of exercise may soon surpass tobacco as a leading cause of death. These behaviors are modifiable and public health and prevention efforts could make a difference to reduce these deaths.
|Cause||Deaths caused||% of all deaths|
|Poor diet and physical inactivity||400,000||16.6|
|Sexually transmitted infections||20,000||0.8|
The leading causes of preventable death worldwide share similar trends to the United States. There are a few differences between the two, such as malnutrition, pollution, and unsafe sanitation, that reflect health disparities between the developing and developed world.
|Cause||Deaths caused (millions per year)|
|Sexually transmitted infections||3.0|
|Overweight and obesity||2.5|
|Indoor air pollution from solid fuels||1.8|
|Unsafe water and poor sanitation||1.6|
In 2010, 7.6 million children died before reaching the age of 5. While this is a decrease from 9.6 million in the year 2000, it is still far from the fourth Millennium Development Goal to decrease child mortality by two-thirds by the year 2015. Of these deaths, about 64% were due to infection (including diarrhea, pneumonia, and malaria). About 40% of these deaths occurred in neonates (children ages 1–28 days) due to pre-term birth complications. The highest number of child deaths occurred in Africa and Southeast Asia. In Africa, almost no progress has been made in reducing neonatal death since 1990. India, Nigeria, Democratic Republic of the Congo, Pakistan, and China contributed to almost 50% of global child deaths in 2010. Targeting efforts in these countries is essential to reducing the global child death rate.
Child mortality is caused by a variety of factors including poverty, environmental hazards, and lack of maternal education. The World Health Organization created a list of interventions in the following table that were judged economically and operationally "feasible," based on the healthcare resources and infrastructure in 42 nations that contribute to 90% of all infant and child deaths. The table indicates how many infant and child deaths could have been prevented in the year 2000, assuming universal healthcare coverage.
|Intervention||Percent of all child deaths preventable|
|Water, sanitation, hygiene||3|
|Newborn temperature management||2|
|Nevirapine and replacement feeding||2|
|Antibiotics for premature rupture of membranes||1|
|Antimalarial intermittent preventive treatment in pregnancy||<1%|
Obesity is a major risk factor for a wide variety of conditions including cardiovascular diseases, hypertension, certain cancers, and type 2 diabetes. In order to prevent obesity, it is recommended that individuals adhere to a consistent exercise regimen as well as a nutritious and balanced diet. A healthy individual should aim for acquiring 10% of their energy from proteins, 15-20% from fat, and over 50% from complex carbohydrates, while avoiding alcohol as well as foods high in fat, salt, and sugar. Sedentary adults should aim for at least half an hour of moderate-level daily physical activity and eventually increase to include at least 20 minutes of intense exercise, three times a week. Preventive health care offers many benefits to those that chose to participate in taking an active role in the culture. The medical system in our society is geared toward curing acute symptoms of disease after the fact that they have brought us into the emergency room. An ongoing epidemic within American culture is the prevalence of obesity. Eating healthier and routinely exercising plays a huge role in reducing an individual's risk for type 2 diabetes. A 2008 study concluded that about 23.6 million people in the United States had diabetes, including 5.7 million that had not been diagnosed. Ninety to 95 percent of people with diabetes have type 2 diabetes. Diabetes is the main cause of kidney failure, limb amputation, and new-onset blindness in American adults.
Sexually transmitted infectionsEdit
Sexually transmitted infections (STIs), such as syphilis and HIV, are common but preventable with safe-sex practices. STIs can be asymptomatic, or cause a range of symptoms. Preventive measures for STIs are called prophylactics. The term especially applies to the use of condoms, which are highly effective at preventing disease, but also to other devices meant to prevent STIs, such as dental dams and latex gloves. Other means for preventing STIs include education on how to use condoms or other such barrier devices, testing partners before having unprotected sex, receiving regular STI screenings, to both receive treatment and prevent spreading STIs to partners, and, specifically for HIV, regularly taking prophylactic antiretroviral drugs, such as Truvada. Post-exposure prophylaxis, started within 72 hours (optimally less than 1 hour) after exposure to high-risk fluids, can also protect against HIV transmission.
Malaria prevention using genetic modificationEdit
Thrombosis is a serious circulatory disease affecting thousands, usually older persons undergoing surgical procedures, women taking oral contraceptives and travelers. Consequences of thrombosis can be heart attacks and strokes. Prevention can include: exercise, anti-embolism stockings, pneumatic devices, and pharmacological treatments.
In recent years, cancer has become a global problem. Low and middle income countries share a majority of the cancer burden largely due to exposure to carcinogens resulting from industrialization and globalization. However, primary prevention of cancer and knowledge of cancer risk factors can reduce over one third of all cancer cases. Primary prevention of cancer can also prevent other diseases, both communicable and non-communicable, that share common risk factors with cancer.
Lung cancer is the leading cause of cancer-related deaths in the United States and Europe and is a major cause of death in other countries. Tobacco is an environmental carcinogen and the major underlying cause of lung cancer. Between 25% and 40% of all cancer deaths and about 90% of lung cancer cases are associated with tobacco use. Other carcinogens include asbestos and radioactive materials. Both smoking and second-hand exposure from other smokers can lead to lung cancer and eventually death. Therefore, prevention of tobacco use is paramount to prevention of lung cancer.
Individual, community, and statewide interventions can prevent or cease tobacco use. 90% of adults in the US who have ever smoked did so prior to the age of 20. In-school prevention/educational programs, as well as counseling resources, can help prevent and cease adolescent smoking. Other cessation techniques include group support programs, nicotine replacement therapy (NRT), hypnosis, and self-motivated behavioral change. Studies have shown long term success rates (>1 year) of 20% for hypnosis and 10%-20% for group therapy.
Cancer screening programs serve as effective sources of secondary prevention. The Mayo Clinic, Johns Hopkins, and Memorial Sloan-Kettering hospitals conducted annual x-ray screenings and sputum cytology tests and found that lung cancer was detected at higher rates, earlier stages, and had more favorable treatment outcomes, which supports widespread investment in such programs.
Legislation can also affect smoking prevention and cessation. In 1992, Massachusetts (United States) voters passed a bill adding an extra 25 cent tax to each pack of cigarettes, despite intense lobbying and $7.3 million spent by the tobacco industry to oppose this bill. Tax revenue goes toward tobacco education and control programs and has led to a decline of tobacco use in the state.
Lung cancer and tobacco smoking are increasing worldwide, especially in China. China is responsible for about one-third of the global consumption and production of tobacco products. Tobacco control policies have been ineffective as China is home to 350 million regular smokers and 750 million passive smokers and the annual death toll is over 1 million. Recommended actions to reduce tobacco use include: decreasing tobacco supply, increasing tobacco taxes, widespread educational campaigns, decreasing advertising from the tobacco industry, and increasing tobacco cessation support resources. In Wuhan, China, a 1998 school-based program implemented an anti-tobacco curriculum for adolescents and reduced the number of regular smokers, though it did not significantly decrease the number of adolescents who initiated smoking. This program was therefore effective in secondary but not primary prevention and shows that school-based programs have the potential to reduce tobacco use.
Skin cancer is the most common cancer in the United States. The most lethal form of skin cancer, melanoma, leads to over 50,000 annual deaths in the United States. Childhood prevention is particularly important because a significant portion of ultraviolet radiation exposure from the sun occurs during childhood and adolescence and can subsequently lead to skin cancer in adulthood. Furthermore, childhood prevention can lead to the development of healthy habits that continue to prevent cancer for a lifetime.
The Centers for Disease Control and Prevention (CDC) recommends several primary prevention methods including: limiting sun exposure between 10 AM and 4 PM, when the sun is strongest, wearing tighter-weave natural cotton clothing, wide-brim hats, and sunglasses as protective covers, using sunscreens that protect against both UV-A and UV-B rays, and avoiding tanning salons. Sunscreen should be reapplied after sweating, exposure to water (through swimming for example) or after several hours of sun exposure. Since skin cancer is very preventable, the CDC recommends school-level prevention programs including preventive curricula, family involvement, participation and support from the school's health services, and partnership with community, state, and national agencies and organizations to keep children away from excessive UV radiation exposure.
Most skin cancer and sun protection data comes from Australia and the United States. An international study reported that Australians tended to demonstrate higher knowledge of sun protection and skin cancer knowledge, compared to other countries. Of children, adolescents, and adults, sunscreen was the most commonly used skin protection. However, many adolescents purposely used sunscreen with a low sun protection factor (SPF) in order to get a tan. Various Australian studies have shown that many adults failed to use sunscreen correctly; many applied sunscreen well after their initial sun exposure and/or failed to reapply when necessary. A 2002 case-control study in Brazil showed that only 3% of case participants and 11% of control participants used sunscreen with SPF >15.
Cervical cancer ranks among the top three most common cancers among women in Latin America, sub-Saharan Africa, and parts of Asia. Cervical cytology screening aims to detect abnormal lesions in the cervix so that women can undergo treatment prior to the development of cancer. Given that high quality screening and follow-up care has been shown to reduce cervical cancer rates by up to 80%, most developed countries now encourage sexually active women to undergo a Pap test every 3–5 years. Finland and Iceland have developed effective organized programs with routine monitoring and have managed to significantly reduce cervical cancer mortality while using fewer resources than unorganized, opportunistic programs such as those in the United States or Canada.
In developing nations in Latin America, such as Chile, Colombia, Costa Rica, and Cuba, both public and privately organized programs have offered women routine cytological screening since the 1970s. However, these efforts have not resulted in a significant change in cervical cancer incidence or mortality in these nations. This is likely due to low quality, inefficient testing. However, Puerto Rico, which has offered early screening since the 1960s, has witnessed almost a 50% decline in cervical cancer incidence and almost a four-fold decrease in mortality between 1950 and 1990. Brazil, Peru, India, and several high-risk nations in sub-Saharan Africa which lack organized screening programs, have a high incidence of cervical cancer.
Colorectal cancer is globally the second most common cancer in women and the third-most common in men, and the fourth most common cause of cancer death after lung, stomach, and liver cancer, having caused 715,000 deaths in 2010.
It is also highly preventable; about 80 percent of colorectal cancers begin as benign growths, commonly called polyps, which can be easily detected and removed during a colonoscopy. Other methods of screening for polyps and cancers include fecal occult blood testing. Lifestyle changes that may reduce the risk of colorectal cancer include increasing consumption of whole grains, fruits and vegetables, and reducing consumption of red meat (see Colorectal cancer).
Health disparities and barriers to accessing careEdit
Access to healthcare and preventive health services is unequal, as is the quality of care received. A study conducted by the Agency for Healthcare Research and Quality (AHRQ) revealed health disparities in the United States. In the United States, elderly adults (>65 years old) received worse care and had less access to care than their younger counterparts. The same trends are seen when comparing all racial minorities (black, Hispanic, Asian) to white patients, and low-income people to high-income people. Common barriers to accessing and utilizing healthcare resources included lack of income and education, language barriers, and lack of health insurance. Minorities were less likely than whites to possess health insurance, as were individuals who completed less education. These disparities made it more difficult for the disadvantaged groups to have regular access to a primary care provider, receive immunizations, or receive other types of medical care. Additionally, uninsured people tend to not seek care until their diseases progress to chronic and serious states and they are also more likely to forgo necessary tests, treatments, and filling prescription medications.
These sorts of disparities and barriers exist worldwide as well. Often, there are decades of gaps in life expectancy between developing and developed countries. For example, Japan has an average life expectancy that is 36 years greater than that in Malawi. Low-income countries also tend to have fewer physicians than high-income countries. In Nigeria and Myanmar, there are fewer than 4 physicians per 100,000 people while Norway and Switzerland have a ratio that is ten-fold higher. Common barriers worldwide include lack of availability of health services and healthcare providers in the region, great physical distance between the home and health service facilities, high transportation costs, high treatment costs, and social norms and stigma toward accessing certain health services.
Economics of lifestyle-based preventionEdit
With lifestyle factors such as diet and exercise rising to the top of preventable death statistics, the economics of healthy lifestyle is a growing concern. There is little question that positive lifestyle choices provide an investment in health throughout life. To gauge success, traditional measures such as the quality years of life method (QALY), show great value. However, that method does not account for the cost of chronic conditions or future lost earnings because of poor health. Developing future economic models that would guide both private and public investments as well as drive future policy to evaluate the efficacy of positive lifestyle choices on health is a major topic for economists globally.
Americans spend over three trillion a year on health care but have a higher rate of infant mortality, shorter life expectancies, and a higher rate of diabetes than other high-income nations because of negative lifestyle choices. Despite these large costs, very little is spent on prevention for lifestyle-caused conditions in comparison. The Journal of the American Medical Association estimates that $101 billion was spent in 2013 on the preventable disease of diabetes, and another $88 billion was spent on heart disease. In an effort to encourage healthy lifestyle choices, workplace wellness programs are on the rise; but the economics and effectiveness data are still continuing to evolve and develop.
Health insurance coverage impacts lifestyle choices. In a study by Sudano and Baker, even intermittent loss of coverage has negative effects on healthy choices. The potential repeal of the Affordable Care Act (ACA) could significantly impact coverage for many Americans, as well as “The Prevention and Public Health Fund” which is our nation's first and only mandatory funding stream dedicated to improving the public's health. Also covered in the ACA is counseling on lifestyle prevention issues, such as weight management, alcohol use, and treatment for depression. Policy makers can have substantial effects on the lifestyle choices made by Americans.
Because chronic illnesses predominate as a cause of death in the US and pathways for treating chronic illnesses are complex and multifaceted, prevention is a best practice approach to chronic disease when possible. In many cases, prevention requires mapping complex pathways to determine the ideal point for intervention. Cost-effectiveness of prevention is achievable, but impacted by the length of time it takes to see effects/outcomes of intervention. This makes prevention efforts difficult to fund—particularly in strained financial contexts. Prevention potentially creates other costs as well, due to extending the lifespan and thereby increasing opportunities for illness. In order to assess the cost-effectiveness of prevention, the cost of the preventive measure, savings from avoiding morbidity, and the cost from extending the lifespan need to be considered. Life extension costs become smaller when accounting for savings from postponing the last year of life, which makes up a large fraction of lifetime medical expenditures and becomes cheaper with age. Prevention leads to savings only if the cost of the preventive measure is less than the savings from avoiding morbidity net of the cost of extending the life span. In order to establish reliable economics of prevention for illnesses that are complicated in origin, knowing how best to assess prevention efforts, i.e. developing useful measures and appropriate scope, is required.
There is no general consensus as to whether or not preventive healthcare measures are cost-effective, but they increase the quality of life dramatically. There are varying views on what constitutes a "good investment." Some argue that preventive health measures should save more money than they cost, when factoring in treatment costs in the absence of such measures. Others argue in favor of "good value" or conferring significant health benefits even if the measures do not save money. Furthermore, preventive health services are often described as one entity though they comprise a myriad of different services, each of which can individually lead to net costs, savings, or neither. Greater differentiation of these services is necessary to fully understand both the financial and health effects.
A 2010 study reported that in the United States, vaccinating children, cessation of smoking, daily prophylactic use of aspirin, and screening of breast and colorectal cancers had the most potential to prevent premature death. Preventive health measures that resulted in savings included vaccinating children and adults, smoking cessation, daily use of aspirin, and screening for issues with alcoholism, obesity, and vision failure. These authors estimated that if usage of these services in the United States increased to 90% of the population, there would be net savings of $3.7 billion, which comprised only about -0.2% of the total 2006 United States healthcare expenditure. Despite the potential for decreasing healthcare spending, utilization of healthcare resources in the United States still remains low, especially among Latinos and African-Americans. Overall, preventive services are difficult to implement because healthcare providers have limited time with patients and must integrate a variety of preventive health measures from different sources.
While these specific services bring about small net savings not every preventive health measure saves more than it costs. A 1970s study showed that preventing heart attacks by treating hypertension early on with drugs actually did not save money in the long run. The money saved by evading treatment from heart attack and stroke only amounted to about a quarter of the cost of the drugs. Similarly, it was found that the cost of drugs or dietary changes to decrease high blood cholesterol exceeded the cost of subsequent heart disease treatment. Due to these findings, some argue that rather than focusing healthcare reform efforts exclusively on preventive care, the interventions that bring about the highest level of health should be prioritized.
Cohen et al. (2008) outline a few arguments made by skeptics of preventive healthcare. Many argue that preventive measures only cost less than future treatment when the proportion of the population that would become ill in the absence of prevention is fairly large. The Diabetes Prevention Program Research Group conducted a 2012 study evaluating the costs and benefits (in quality-adjusted life-years or QALYs) of lifestyle changes versus taking the drug metformin. They found that neither method brought about financial savings, but were cost-effective nonetheless because they brought about an increase in QALYs. In addition to scrutinizing costs, preventive healthcare skeptics also examine efficiency of interventions. They argue that while many treatments of existing diseases involve use of advanced equipment and technology, in some cases, this is a more efficient use of resources than attempts to prevent the disease. Cohen et al. (2008) suggest that the preventive measures most worth exploring and investing in are those that could benefit a large portion of the population to bring about cumulative and widespread health benefits at a reasonable cost.
- Cost-effectiveness of childhood obesity interventions
There are at least four nationally implemented childhood obesity interventions in the United States: the Sugar-Sweetened Beverage excise tax (SSB), the TV AD program, active physical education (Active PE) policies, and early care and education (ECE) policies. They each have similar goals of reducing childhood obesity. The effects of these interventions on BMI have been studied, and the cost-effectiveness analysis (CEA) has led to a better understanding of projected cost reductions and improved health outcomes. The Childhood Obesity Intervention Cost-Effectiveness Study (CHOICES) was conducted to evaluate and compare the CEA of these four interventions.
Gortmaker, S.L. et al. (2015) states: "The four initial interventions were selected by the investigators to represent a broad range of nationally scalable strategies to reduce childhood obesity using a mix of both policy and programmatic strategies... 1. an excise tax of $0.01 per ounce of sweetened beverages, applied nationally and administered at the state level (SSB), 2. elimination of the tax deductibility of advertising costs of TV advertisements for "nutritionally poor" foods and beverages seen by children and adolescents (TV AD), 3. state policy requiring all public elementary schools in which physical education (PE) is currently provided to devote ≥50% of PE class time to moderate and vigorous physical activity (Active PE), and 4. state policy to make early child educational settings healthier by increasing physical activity, improving nutrition, and reducing screen time (ECE)."
The CHOICES found that SSB, TV AD, and ECE led to net cost savings. Both SSB and TV AD increased quality adjusted life years and produced yearly tax revenue of 12.5 billion US dollars and 80 million US dollars, respectively.
Some challenges with evaluating the effectiveness of child obesity interventions include:
- The economic consequences of childhood obesity are both short and long term. In the short term, obesity impairs cognitive achievement and academic performance. Some believe this is secondary to negative effects on mood or energy, but others suggest there may be physiological factors involved. Furthermore, obese children have increased health care expenses (e.g. medications, acute care visits). In the long term, obese children tend to become obese adults with associated increased risk for a chronic condition such as diabetes or hypertension. Any effect on their cognitive development may also affect their contributions to society and socioeconomic status.
- In the CHOICES, it was noted that translating the effects of these interventions may in fact differ among communities throughout the nation. In addition it was suggested that limited outcomes are studied and these interventions may have an additional effect that is not fully appreciated.
- Modeling outcomes in such interventions in children over the long term is challenging because advances in medicine and medical technology are unpredictable. The projections from cost-effective analysis may need to be reassessed more frequently.
- The economics of preventive care in the US
The cost-effectiveness of preventive care is a highly debated topic. While some economists argue that preventive care is valuable and potentially cost saving, others believe it is an inefficient waste of resources. Preventive care is composed of a variety of clinical services and programs including annual doctor's check-ups, annual immunizations, and wellness programs; recent models show that these simple interventions can have significant economic impacts.
Clinical preventive services & programs
Research on preventive care addresses the question of whether it is cost saving or cost effective and whether there is an economics evidence base for health promotion and disease prevention. The need for and interest in preventive care is driven by the imperative to reduce health care costs while improving quality of care and the patient experience. Preventive care can lead to improved health outcomes and cost savings potential. Services such as health assessments/screenings, prenatal care, and telehealth and telemedicine can reduce morbidity or mortality with low cost or cost savings. Specifically, health assessments/screenings have cost savings potential, with varied cost-effectiveness based on screening and assessment type. Inadequate prenatal care can lead to an increased risk of prematurity, stillbirth, and infant death. Time is the ultimate resource and preventive care can help mitigate the time costs. Telehealth and telemedicine is one option that has gained consumer interest, acceptance and confidence and can improve quality of care and patient satisfaction.
Understanding the economics for investment
There are benefits and trade-offs when considering investment in preventive care versus other types of clinical services. Preventive care can be a good investment as supported by the evidence base and can drive population health management objectives. The concepts of cost saving and cost-effectiveness are different and both are relevant to preventive care. For example, preventive care that may not save money may still provide health benefits. Thus, there is a need to compare interventions relative to impact on health and cost.
Preventive care transcends demographics and is applicable to people of every age. The Health Capital Theory underpins the importance of preventive care across the lifecycle and provides a framework for understanding the variances in health and health care that are experienced. It treats health as a stock that provides direct utility. Health depreciates with age and the aging process can be countered through health investments. The theory further supports that individuals demand good health, that the demand for health investment is a derived demand (i.e. investment is health is due to the underlying demand for good health), and the efficiency of the health investment process increases with knowledge (i.e. it is assumed that the more educated are more efficient consumers and producers of health).
The prevalence elasticity of demand for prevention can also provide insights into the economics. Demand for preventive care can alter the prevalence rate of a given disease and further reduce or even reverse any further growth of prevalence. Reduction in prevalence subsequently leads to reduction in costs.
Economics for policy action
There are a number of organizations and policy actions that are relevant when discussing the economics of preventive care services. The evidence base, viewpoints, and policy briefs from the Robert Wood Johnson Foundation, the Organisation for Economic Co-operation and Development (OECD), and efforts by the U.S. Preventive Services Task Force (USPSTF) all provide examples that improve the health and well-being of populations (e.g. preventive health assessments/screenings, prenatal care, and telehealth/telemedicine). The Patient Protection and Affordable Care Act (PPACA, ACA) has major influence on the provision of preventive care services, although it is currently under heavy scrutiny and review by the new administration. According to the Centers for Disease Control and Prevention (CDC), the ACA makes preventive care affordable and accessible through mandatory coverage of preventive services without a deductible, copayment, coinsurance, or other cost sharing.
The U.S. Preventive Services Task Force (USPSTF), a panel of national experts in prevention and evidence-based medicine, works to improve health of Americans by making evidence-based recommendations about clinical preventive services. They do not consider the cost of a preventive service when determining a recommendation. Each year, the organization delivers a report to Congress that identifies critical evidence gaps in research and recommends priority areas for further review.
The National Network of Perinatal Quality Collaboratives (NNPQC), sponsored by the CDC, supports state-based perinatal quality collaboratives (PQCs) in measuring and improving upon health care and health outcomes for mothers and babies. These PQCs have contributed to improvements such as reduction in deliveries before 39 weeks, reductions in healthcare associated blood stream infections, and improvements in the utilization of antenatal corticosteroids.
Telehealth and telemedicine has realized significant growth and development recently. The Center for Connected Health Policy (The National Telehealth Policy Resource Center) has produced multiple reports and policy briefs on the topic of Telehealth and Telemedicine and how they contribute to preventive services.
Policy actions and provision of preventive services do not guarantee utilization. Reimbursement has remained a significant barrier to adoption due to variances in payer and state level reimbursement policies and guidelines through government and commercial payers. Americans use preventive services at about half the recommended rate and cost-sharing, such as deductibles, co-insurance, or copayments, also reduce the likelihood that preventive services will be used. Further, despite the ACA's enhancement of Medicare benefits and preventive services, there were no effects on preventive service utilization, calling out the fact that other fundamental barriers exist.
- The Affordable Care Act and preventive healthcare
The Patient Protection and Affordable Care Act, also known as just the Affordable Care Act or Obamacare, was passed and became law in the United States on March 23, 2010. The finalized and newly ratified law was to address many issues in the U.S. healthcare system, which included expansion of coverage, insurance market reforms, better quality, and the forecast of efficiency and costs. Under the insurance market reforms the act required that insurance companies no longer exclude people with pre-existing conditions, allow for children to be covered on their parents' plan until the age of 26, and expand appeals that dealt with reimbursement denials. The Affordable Care Act also banned the limited coverage imposed by health insurances, and insurance companies were to include coverage for preventive health care services. The U.S. Preventive Services Task Force has categorized and rated preventive health services as either ‘”A” or “B”, as to which insurance companies must comply and present full coverage. Not only has the U.S. Preventive Services Task Force provided graded preventive health services that are appropriate for coverage, they have also provided many recommendations to clinicians and insurers to promote better preventive care to ultimately provide better quality of care and lower the burden of costs.
Health insurance and preventive care
Healthcare insurance companies are willing to pay for preventive care despite the fact that patients are not acutely sick in hope that it will prevent them from developing a chronic disease later on in life. Today, health insurance plans offered through the Marketplace, mandated by the Affordable Care Act are required to provide certain preventive care services free of charge to patients. Section 2713 of the Affordable Care Act, specifies that all private Marketplace and all employer-sponsored private plans (except those grandfathered in) are required to cover preventive care services that are ranked A or B by the US Preventive Services Task Force free of charge to patients. For example, UnitedHealthcare insurance company has published patient guidelines at the beginning of the year explaining their preventive care coverage.
Evaluating incremental benefits of preventive care
Evaluating the incremental benefits of preventive care requires a longer period of time when compared to acutely ill patients. Inputs into the model such as discounting rate and time horizon can have significant effects on the results. One controversial subject is use of a 10-year time frame to assess cost effectiveness of diabetes preventive services by the Congressional Budget Office.
The preventive care services mainly focus on chronic disease. The Congressional Budget Office has provided guidance that further research is needed in the area of the economic impacts of obesity in the US before the CBO can estimate budgetary consequences. A bipartisan report published in May 2015 recognizes the potential of preventive care to improve patients' health at individual and population levels while decreasing the healthcare expenditure.
An economic case for preventive health
Mortality from modifiable risk factors
Chronic diseases such as heart disease, stroke, diabetes, obesity and cancer have become the most common and costly health problems in the United States. In 2014, it was projected that by 2023 that the number of chronic disease cases would increase by 42%, resulting in $4.2 trillion in treatment and lost economic output. They are also among the top ten leading causes of mortality. Chronic diseases are driven by risk factors that are largely preventable. Sub-analysis performed on all deaths in the United States in the year 2000 revealed that almost half were attributed to preventable behaviors including tobacco, poor diet, physical inactivity and alcohol consumption. More recent analysis reveals that heart disease and cancer alone accounted for nearly 46% of all deaths. Modifiable risk factors are also responsible for a large morbidity burden, resulting in poor quality of life in the present and loss of future life earning years. It is further estimated that by 2023, focused efforts on the prevention and treatment of chronic disease may result in 40 million fewer chronic disease cases, potentially reducing treatment costs by $220 billion.
Childhood vaccinations reduce health care costs
Childhood immunizations are largely responsible for the increase in life expectancy in the 20th century. From an economic standpoint, childhood vaccines demonstrate a very high return on investment. According to Healthy People 2020, for every birth cohort that receives the routine childhood vaccination schedule, direct health care costs are reduced by $9.9 billion and society saves $33.4 billion in indirect costs. The economic benefits of childhood vaccination extend beyond individual patients to insurance plans and vaccine manufacturers, all while improving the health of the population.
Prevention and health capital theory
The burden of preventable illness extends beyond the healthcare sector, incurring significant costs related to lost productivity among workers in the workforce. Indirect costs related to poor health behaviors and associated chronic disease costs U.S. employers billions of dollars each year.
According to the American Diabetes Association (ADA), medical costs for employees with diabetes are twice as high as for workers without diabetes and are caused by work-related absenteeism ($5 billion), reduced productivity at work ($20.8 billion), inability to work due to illness-related disability ($21.6 billion), and premature mortality ($18.5 billion). Reported estimates of the cost burden due to increasingly high levels of overweight and obese members in the workforce vary, with best estimates suggesting 450 million more missed work days, resulting in $153 billion each year in lost productivity, according to the CDC Healthy Workforce.
In the field of economics, the Health Capital model explains how individual investments in health can increase earnings by “increasing the number of healthy days available to work and to earn income.” In this context, health can be treated both as a consumption good, wherein individuals desire health because it improves quality of life in the present, and as an investment good because of its potential to increase attendance and workplace productivity over time. Preventive health behaviors such as healthful diet, regular exercise, access to and use of well-care, avoiding tobacco, and limiting alcohol can be viewed as health inputs that result in both a healthier workforce and substantial cost savings.
Preventive care and quality adjusted life years
Health benefits of preventive care measures can be described in terms of quality-adjusted life-years (QALYs) saved. A QALY takes into account length and quality of life, and is used to evaluate the cost-effectiveness of medical and preventive interventions. Classically, one year of perfect health is defined as 1 QALY and a year with any degree of less than perfect health is assigned a value between 0 and 1 QALY. As an economic weighting system, the QALY can be used to inform personal decisions, to evaluate preventive interventions and to set priorities for future preventive efforts.
Cost-saving and cost-effective benefits of preventive care measures are well established. The Robert Wood Johnson Foundation evaluated the prevention cost-effectiveness literature, and found that many preventive measures meet the benchmark of <$100,000 per QALY and are considered to be favorably cost-effective. These include screenings for HIV and chlamydia, cancers of the colon, breast and cervix, vision screening, and screening for abdominal aortic aneurysms in men >60 in certain populations. Alcohol and tobacco screening were found to be cost-saving in some reviews and cost-effective in others. According to the RWJF analysis, two preventive interventions were found to save costs in all reviews: childhood immunizations and counseling adults on the use of aspirin.
Prevention in minority populations
Health disparities are increasing in the United States for chronic diseases such as obesity, diabetes, cancer, and cardiovascular disease. Populations at heightened risk for health inequities are the growing proportion of racial and ethnic minorities, including African Americans, American Indians, Hispanics/Latinos, Asian Americans, Alaska Natives and Pacific Islanders.
According to the Racial and Ethnic Approaches to Community Health (REACH), a national CDC program, non-Hispanic blacks currently have the highest rates of obesity (48%), and risk of newly diagnosed diabetes is 77% higher among non-Hispanic blacks, 66% higher among Hispanics/Latinos and 18% higher among Asian Americans compared to non-Hispanic whites. Current U.S. population projections predict that more than half of Americans will belong to a minority group by 2044. Without targeted preventive interventions, medical costs from chronic disease inequities will become unsustainable. Broadening health policies designed to improve delivery of preventive services for minority populations may help reduce substantial medical costs caused by inequities in health care, resulting in a return on investment.
Policies of prevention
Chronic disease is a population level issue that requires population health level efforts and national and state level public policy to effectively prevent, rather than individual level efforts. The United States currently employs many public health policy efforts aligned with the preventive health efforts discussed above. For instance, the Centers for Disease Control and Prevention support initiatives such as Health in All Policies and HI-5 (Health Impact in 5 Years), collaborative efforts that aim to consider prevention across sectors and address social determinants of health as a method of primary prevention for chronic disease. Specific examples of programs targeting vaccination and obesity prevention in childhood are discussed in the sections to follow.
Policy prevention of obesity
Policies that address the obesity epidemic should be proactive and far-reaching, including a variety of stakeholders both in healthcare and in other sectors. Recommendations from the Institute of Medicine in 2012 suggest that “…concerted action be taken across and within five environments (physical activity (PA), food and beverage, marketing and messaging, healthcare and worksites, and schools) and all sectors of society (including government, business and industry, schools, child care, urban planning, recreation, transportation, media, public health, agriculture, communities, and home) in order for obesity prevention efforts to truly be successful.”
There are dozens of current policies acting at either (or all of) the federal, state, local and school levels. Most states employ a physical education requirement of 150 minutes of physical education per week at school, a policy of the National Association of Sport and Physical Education. In some cities, including Philadelphia, a sugary food tax is employed. This is a part of an amendment to Title 19 of the Philadelphia Code, “Finance, Taxes and Collections”; Chapter 19-4100, “Sugar-Sweetened Beverage Tax, that was approved 2016, which establishes an excise tax of $0.015 per fluid ounce on distributors of beverages sweetened with both caloric and non-caloric sweeteners. Distributors are required to file a return with the department, and the department can collect taxes, among other responsibilities.
These policies can be a source of tax credits. For example, under the Philadelphia policy, businesses can apply for tax credits with the revenue department on a first-come, first-served basis. This applies until the total amount of credits for a particular year reaches one million dollars.
Recently, advertisements for food and beverages directed at children have received much attention. The Children's Food and Beverage Advertising Initiative (CFBAI) is a self-regulatory program of the food industry. Each participating company makes a public pledge that details its commitment to advertise only foods that meet certain nutritional criteria to children under 12 years old. This is a self-regulated program with policies written by the Council of Better Business Bureaus. The Robert Wood Johnson Foundation funded research to test the efficacy of the CFBAI. The results showed progress in terms of decreased advertising of food products that target children and adolescents.
To explore other programs and initiatives related to policies of childhood obesity, visit the following organizations and online databases: U.S. Department of Agriculture, Robert Wood Johnson Foundation-supported Bridging the Gap Program, National Association of County and City Health Officials, Yale Rudd Center for Food Policy & Obesity, Centers for Disease Control and Prevention's Chronic Disease State Policy Tracking System, National Conference of State Legislatures, Prevention Institute's ENACT local policy database, Organization for Economic Cooperation and Development (OECD), and the U.S. Preventive Services Task Force (USPSTF).
Childhood immunization policies
Despite nationwide controversies over childhood vaccination and immunization, there are policies and programs at the federal, state, local and school levels outlining vaccination requirements. All states require children to be vaccinated against certain communicable diseases as a condition for school attendance. However, currently 18 states allow exemptions for “philosophical or moral reasons.” Diseases for which vaccinations form part of the standard ACIP vaccination schedule are diphtheria tetanus pertussis (whooping cough), poliomyelitis (polio), measles, mumps, rubella, haemophilus influenzae type b, hepatitis B, influenza, and pneumococcal infections. These schedules can be viewed on the CDC website.
The CDC website describes a federally funded program, Vaccines for Children (VFC), which provides vaccines at no cost to children who might not otherwise be vaccinated because of inability to pay. Additionally, the Advisory Committee on Immunization Practices (ACIP) is an expert vaccination advisory board that informs vaccination policy and guides on-going recommendations to the CDC, incorporating the most up-to-date cost-effectiveness and risk-benefit evidence in its recommendations.
An economic case conclusion
There are economic and health related arguments for preventive healthcare. Direct and indirect medical costs related to preventable chronic disease are high, and will continue to rise with an aging and increasingly diverse U.S. population. The government, at federal, state, local and school levels has acknowledged this and created programs and policies to support chronic disease prevention, notably at the childhood age, and focusing on obesity prevention and vaccination. Economically, with an increase in QALY and a decrease in lost productivity over a lifetime, existing and innovative prevention interventions demonstrate a high return on investment and are expected to result in substantial healthcare cost-savings over time.
- American Board of Preventive Medicine
- American Journal of Preventive Medicine
- American Osteopathic Board of Preventive Medicine
- Mental illness prevention
- Pre-exposure prophylaxis
- Preventive Medicine (journal)
- Primary Health Care
- Screening (medicine)
- Treatment as prevention
- United States Preventive Services Task Force (USPSTF)
- Hugh R. Leavell and E. Gurney Clark as "the science and art of preventing disease, prolonging life, and promoting physical and mental health and efficiency. Leavell, H. R., & Clark, E. G. (1979). Preventive Medicine for the Doctor in his Community (3rd ed.). Huntington, NY: Robert E. Krieger Publishing Company.
- ""New parents" secure a lifelong well-being for their offspring by refusing to be victims of societal stress during its primal period". Primal Prevention.
- Primal Health Research Database, on https://web.archive.org/web/20180815043657/http://primalhealthresearch.com/glossary.php
- Mokdad A. H., Marks J. S., Stroup D. F., Gerberding J. L. (2004). "Actual Causes of Death in the United States, 2000". Journal of the American Medical Association. 291 (10): 1238–1245. doi:10.1001/jama.291.10.1238. PMID 15010446.CS1 maint: multiple names: authors list (link)
- The Top 10 Causes of Death. (n.d.). Retrieved March 16, 2014, from World Health Organization website: http://www.who.int/mediacentre/factsheets/fs310/en/index2.html
- LeChelle Saunders, BSc: Smoking is Critical to Our Health. Be Smart, Don’t Start
- Isensee B, Hanewinkel R (2018). "[School-based tobacco prevention: the "Be Smart - Don't Start" program]". Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz. 61 (11): 1446–1452. doi:10.1007/s00103-018-2825-9. PMID 30276431.
- Thrul Johannes, Bühler Anneke, Herth Felix J.F. (2014). "Prevention of teenage smoking through negative information giving, a cluster randomized controlled trial". Drugs: Education, Prevention and Policy. 21: 35–42. doi:10.3109/09687637.2013.798264.CS1 maint: multiple names: authors list (link)
- ‘Be Smart, Don’t Start’ campaign launched to deter youths from smoking
- Vorvick, L. (2013). Preventive health care. In D. Zieve, D. R. Eltz, S. Slon, & N. Wang (Eds.), The A.D.A.M. Medical Encyclopedia. Retrieved from https://www.nlm.nih.gov/medlineplus/encyclopedia.html
- Maciosek Michael V., Coffield Ashley B., Flottemesch Thomas J., Edwards Nichol M., Solberg Leif I. (2010). "Greater Use Of Preventive Services In U.S. Health Care Could Save Lives At Little Or No Cost". Health Affairs. 29 (9): 1656–1660. doi:10.1377/hlthaff.2008.0701. PMID 20820022.CS1 maint: multiple names: authors list (link)
- Cohen J.T., Neumann P.J., Weinstein M.C. (2008). "Does Preventive Care Save Money? Health Economics and the Presidential Candidates". New England Journal of Medicine. 358 (7): 661–663. doi:10.1056/nejmp0708558. PMID 18272889.CS1 maint: multiple names: authors list (link)
- Goldston, S. E. (Ed.). (1987). Concepts of primary prevention: A framework for program development. Sacramento, California Department of Mental Health
- Baker, Sara Josephine. Fighting for Life.1939.
- Darnell, James, RNA, Life's Indispensable Molecule, Cold Spring Harbor Laboratory Press, 2011
- see: http://www.primalprevention.org
- Gillman MW (2015). "Primordial Prevention of Cardiovascular Disease". Circulation. 131 (7): 599–601. doi:10.1161/circulationaha.115.014849. PMC 4349501. PMID 25605661.
- Chiolero A; et al. (2015). "The pseudo-high-risk prevention strategy". Int J Epidemiol. 44 (5): 1469–1473. doi:10.1093/ije/dyv102. PMID 26071137.
- Katz, D., & Ather, A. (2009). Preventive Medicine, Integrative Medicine & The Health of The Public. Commissioned for the IOM Summit on Integrative Medicine and the Health of the Public. Retrieved from "Archived copy" (PDF). Archived from the original (PDF) on 2010-08-27. Retrieved 2014-03-16.CS1 maint: archived copy as title (link)
- Patterson C., Chambers L. W. (1995). "Preventive health care". The Lancet. 345 (8965): 1611–1615. doi:10.1016/s0140-6736(95)90119-1. PMID 7783540.
- Gofrit ON, Shemer J, Leibovici D, Modan B, Shapira SC. Quaternary prevention: a new look at an old challenge. Isr Med Assoc J. 2000;2(7):498-500.
- Perry, Bruce D, Maltreated Children: Experience, Brain Development and the Next Generation, Norton Professional Books, 1996
- Gluckman, Peter D.; Hanson, Mark A.; Cooper, Cyrus; Thornburg, Kent L. (3 July 2008). "Effect of In Utero and Early-Life Conditions on Adult Health and Disease". The New England Journal of Medicine. 359 (1): 61–73. doi:10.1056/NEJMra0708473. PMC 3923653. PMID 18596274.
- Scherrer et al., Systemic and Pulmonary Vascular Dysfunction in Children Conceived by Assisted Reproductive Technologies, Swiss Cardiovascular Center, Bern, CH; Facultad de Ciencias, Departamento de Biologia, Tarapaca, Arica, Chile: Hirslander Group, Lausanne, CH; Botnar Cemter for Extreme Medicine and Department of Internal Medicine, CHUV, Lausanne, CH, and Centre de Procréation Médicalement Assistée, Lausanne, CH, 2012
- Gollwitzer, Eva S.; Marsland, Benjamin J. (November 2015). "Impact of Early-Life Exposures on Immune Maturation and Susceptibility to Disease". Trends in Immunology. 36 (11): 684–696. doi:10.1016/j.it.2015.09.009. PMID 26497259.
- Garcia, Patricia, Why Silicon Valley’s Paid Leave Policies Need to Go Viral, Vogue, culture, opinion, 2015
- Marucs, Erin (2014-04-07). "Access to Good Food as Preventive Medicine". The Atlantic. Atlantic Media Company. Retrieved 11 April 2015.
- "Food Deserts". Food is Power.org. Retrieved 11 April 2015.
- "GreenThumb". NYC Parks. Retrieved 11 April 2015.
- "It's a Market on a Bus". Twin Cities Mobile Market. Retrieved 11 April 2015.
- Module 13: Levels of Disease Prevention. (2007, April 24). Retrieved March 16, 2014, from Centers for Disease Control and Prevention website: https://www.cdc.gov/excite/skincancer/mod13.htm
- Lopez AD, Mathers CD, Ezzati M, Jamison DT, Murray CJ (2006). "Global and regional burden of disease and risk factors, 2001: systematic analysis of population health data". Lancet. 367 (9524): 1747–57. doi:10.1016/s0140-6736(06)68770-9. PMID 16731270.
- Liu L., Johnson H. L., Cousens S., Perin J., Scott S., Lawn J. E., Black R. E. (2012). "Global, regional, and national causes of child mortality: an updated systematic analysis for 2010 with time trends since 2000". The Lancet. 379 (9832): 2151–2161. doi:10.1016/s0140-6736(12)60560-1. PMID 22579125.CS1 maint: multiple names: authors list (link)
- Countdown to 2015, decade report (2000–10)—taking stock of maternal, newborn and child survival WHO, Geneva (2010)
- Jones G, Steketee R, Black R, Bhutta Z, Morris S (2003). "How many child deaths can we prevent this year?". Lancet. 362 (9377): 65–71. doi:10.1016/s0140-6736(03)13811-1. PMID 12853204.
- Kumanyika, S; Jeffery, R; Ritenbaugh, C; Antipatis, VJ (2002). "Obesity prevention: the case for action". International Journal of Obesity. 26 (3): 425–436. doi:10.1038/sj.ijo.0801938. PMID 11896500.
- Kumanyika S., Jeffery R. W., Morabia A., Ritenbaugh C., Antipatis V. J. (2002). "Obesity prevention: the case for action". International Journal of Obesity. 26 (3): 425–436. doi:10.1038/sj.ijo.0801938. PMID 11896500.CS1 maint: multiple names: authors list (link)
- "Diabetes Prevention Program (DPP)." Diabetes Prevention Program (DPP). US Department of Health and Human Services, Oct. 2008. Web. 23 Apr. 2016.http://www.niddk.nih.gov/about-niddk/research-areas/diabetes/diabetes-prevention-program-dpp/Pages/default.aspx
- "Prophylactic". Merriam-Webster. Retrieved December 30, 2018.
- Centers for Disease Control and Prevention. 2014. 2013 Sexually Transmitted Disease Surveillance. Retrieved from: https://www.cdc.gov/std/stats13/syphilis.htm
- W. Takken, T.W. Scott (1991). Ecological Aspects for Application of Genetically Modified Mosquitoes. Science. University of California. pp. X. ISBN 9781402015854.
- Vineis P., Wild C. P. (2014). "Global cancer patterns: causes and prevention". The Lancet. 383 (9916): 549–57. doi:10.1016/s0140-6736(13)62224-2. PMID 24351322.
- Goodman G. E. (2000). "Prevention of lung cancer". Critical Reviews in Oncology/Hematology. 33 (3): 187–197. doi:10.1016/s1040-8428(99)00074-8. PMID 10789492.
- Risser, N. L. (1996). Prevention of Lung Cancer: The Key Is to Stop Smoking. Seminars in Oncology Nursing, 12, 260-269.
- Koh H. K. (1996). "An analysis of the successful 1992 Massachusetts tobacco tax initiative". Tobacco Control. 5 (3): 220–225. doi:10.1136/tc.5.3.220. PMC 1759517. PMID 9035358.
- Zhang J., Ou J., Bai C. (2011). "Tobacco smoking in China: Prevalence, disease burden, challenges and future strategies". Respirology. 16 (8): 1165–1172. doi:10.1111/j.1440-1843.2011.02062.x. PMID 21910781.CS1 maint: multiple names: authors list (link)
- Chou C. P., Li Y., Unger J. B., Xia J., Sun P., Guo Q., Johnson C. A. (2006). "A randomized intervention of smoking for adolescents in urban Wuhan, China". Preventive Medicine. 42 (4): 280–285. doi:10.1016/j.ypmed.2006.01.002. PMID 16487998.CS1 maint: multiple names: authors list (link)
- MMWR. Recommendations and Reports : Morbidity and Mortality Weekly Report. Recommendations and Reports / Centers for Disease Control [2002, 51(RR-4):1-18]
- Stanton W. R., Janda M., Baade P. D., Anderson P. (2004). "Primary prevention of skin cancer: a review of sun protection in Australia and internationally". Health Promotion International. 19 (3): 369–378. doi:10.1093/heapro/dah310. PMID 15306621.CS1 maint: multiple names: authors list (link)
- Broadstock M (1991). "Sun protection at cricket". Medical Journal of Australia. 154 (6): 430. doi:10.5694/j.1326-5377.1991.tb121157.x.
- Pincus M. W., Rollings P. K., Craft A. B., Green B. (1991). "Sunscreen use on Queensland beaches". Australasian Journal of Dermatology. 32 (1): 21–25. doi:10.1111/j.1440-0960.1991.tb00676.x. PMID 1930002.CS1 maint: multiple names: authors list (link)
- Hill D., White V., Marks R., Theobald T., Borland R., Roy C. (1992). "Melanoma prevention: behavioural and non-behavioural factors in sunburn among an Australian urban population". Preventive Medicine. 21 (5): 654–669. doi:10.1016/0091-7435(92)90072-p. PMID 1438112.CS1 maint: multiple names: authors list (link)
- Bakos L., Wagner M., Bakos R. M., Leite C. S. M., Sperhacke C. L., Dzekaniak K. S.; et al. (2002). "Sunburn, sunscreens, and phenotypes: some risk factors for cutaneous melanoma in southern Brazil". International Journal of Dermatology. 41 (9): 557–562. doi:10.1046/j.1365-4362.2002.01412.x. PMID 12358823.CS1 maint: multiple names: authors list (link)
- Sankaranarayanan R., Budukh A. M., Rajkumar R. (2001). "Effective screening programmes for cervical cancer in low- and middle-income developing countries". Bulletin of the World Health Organization. 79 (10): 954–962. PMC 2566667. PMID 11693978.CS1 maint: multiple names: authors list (link)
- World Cancer Report 2014. International Agency for Research on Cancer, World Health Organization. 2014. ISBN 978-92-832-0432-9.
- "Cancer". World Health Organization. February 2010. Retrieved January 5, 2011.
- Lozano R; Naghavi M; Foreman K; et al. (December 2012). "Global and regional mortality from 235 causes of death for 20 age groups in 1990 and 2010: a systematic analysis for the Global Burden of Disease Study 2010". Lancet. 380 (9859): 2095–128. doi:10.1016/S0140-6736(12)61728-0. hdl:10536/DRO/DU:30050819. PMID 23245604.
- Carol A. Burke & Laura K. Bianchi. "Colorectal Neoplasia". Cleveland Clinic. Retrieved January 12, 2015.
- Disparities in Healthcare Quality Among Racial and Ethnic Groups: Selected Findings from the 2011 National Healthcare Quality and Disparities Reports. Fact Sheet. AHRQ Publication No. 12-0006-1-EF, September 2012. Agency for Healthcare Research and Quality, Rockville, MD. http://www.ahrq.gov/qual/nhqrdr11/nhqrdrminority11.htm
- Carrillo J. Emilio, Carrillo Victor A., Perez Hector R., Salas-Lopez Debbie, Natale-Pereira Ana, Byron Alex T. (2011). "Defining and Targeting Health Care Access Barriers". Journal of Health Care for the Poor and Underserved. 22 (2): 562–575. doi:10.1353/hpu.2011.0037. PMID 21551934.CS1 maint: multiple names: authors list (link)
- Fact file on health inequities. (n.d.). Retrieved April 25, 2014, from World Health Organization website: http://www.who.int/sdhconference/background/news/facts/en/
- Jacobs, B., Ir, P., Bigdeli, M., Annear, P. L., & Damme, W. V. (2011). Addressing access barriers to health services: an analytical framework for selecting appropriate interventions in low-income Asian countries. Health Policy and Planning, 1-13.
- Medicine, Institute of Medicine (US) Roundtable on Evidence-Based; Yong, Pierre L.; Saunders, Robert S.; Olsen, LeighAnne (2010-01-01). Missed Prevention Opportunities. National Academies Press (US).
- Arenas, Daniel J.; Lett, Lanair A.; Klusaritz, Heather; Teitelman, Anne M.; van Wouwe, Jacobus P. (28 December 2017). "A Monte Carlo simulation approach for estimating the health and economic impact of interventions provided at a student-run clinic". PLOS ONE. 12 (12): e0189718. Bibcode:2017PLoSO..1289718A. doi:10.1371/journal.pone.0189718. PMID 29284026.
- Miller, Wilhelmine; Grady, Michael O.; Jean-Ezra Yeung; Eichner, June; McMahon, Megan; Rein, David B. (2013). "A Review and Analysis of Economic Models of Prevention Benefits". doi:10.13140/RG.2.1.1225.6803. Cite journal requires
- Frist, B (May 28, 2015). "US Healthcare reform should focus on prevention efforts to cut skyrocketing costs". US News and World Report. Archived from the original on 2015-05-28. Retrieved 2016-03-24.
- Dieleman, Joseph L.; Baral, Ranju; Birger, Maxwell; Bui, Anthony L.; Bulchis, Anne; Chapin, Abigail; Hamavid, Hannah; Horst, Cody; Johnson, Elizabeth K. (2016-12-27). "US Spending on Personal Health Care and Public Health, 1996-2013". JAMA. 316 (24): 2627–2646. doi:10.1001/jama.2016.16885. ISSN 0098-7484. PMC 5551483. PMID 28027366.
- Baicker, Katherine; Cutler, David; Song, Zirui (2010-02-01). "Workplace Wellness Programs Can Generate Savings". Health Affairs. 29 (2): 304–311. doi:10.1377/hlthaff.2009.0626. ISSN 0278-2715. PMID 20075081.
- Sudano, Joseph J.; Baker, David W. (2003-01-01). "Intermittent Lack of Health Insurance Coverage and Use of Preventive Services". American Journal of Public Health. 93 (1): 130–137. doi:10.2105/AJPH.93.1.130. ISSN 0090-0036. PMC 1447707. PMID 12511402.
- "Prevention and Public Health Fund". American Public Health Association. Retrieved 2017-03-24.
- (ASPA), Assistant Secretary for Public Affairs (2013-06-10). "Preventive Care". HHS.gov. Retrieved 2017-03-24.
- Schorr, L.B. (2007). Pathway to the Prevention of Child Abuse and Neglect. http://www.childsworld.ca.gov/res/pdf/Pathway.pdf: Harvard University.
- Gandjour, Afschin (March 2009). "Aging diseases - do they prevent preventive health care from saving costs?". Health Economics. 18 (3): 355–362. doi:10.1002/hec.1370. PMID 18833543.
- Gandjour, A; Lauterbach, KW (July 2005). "Does prevention save costs? Considering deferral of the expensive last year of life". Journal of Health Economics. 24 (4): 715–24. doi:10.1016/j.jhealeco.2004.11.009. PMID 15960993.
- Fuchs, VR (1984). ""Though much is taken": reflections on aging, health, and medical care". The Milbank Memorial Fund Quarterly. Health and Society. 62 (2): 143–66. doi:10.2307/3349821. JSTOR 3349821. PMID 6425716.
- Yang, Z; Norton, EC; Stearns, SC (January 2003). "Longevity and health care expenditures: the real reasons older people spend more". The Journals of Gerontology. Series B, Psychological Sciences and Social Sciences. 58 (1): S2–10. doi:10.1093/geronb/58.1.S2. PMID 12496303.
- "Obesity and the Economics of Prevention | OECD READ edition". OECD iLibrary. Retrieved 2017-03-27.
- Russell Louise B (1993). "The role of prevention in health reform". N Engl J Med. 329 (5): 352–354. doi:10.1056/nejm199307293290511. PMID 8321264.
- Maciosek MV, Coffield AB, Edwards NM, Flottemesch TJ, Goodman MJ, Solberg LI (2006). "Priorities among effective clinical preventive services: results of a systematic review and analysis". Am J Prev Med. 31 (1): 52–61. doi:10.1016/j.amepre.2006.03.012. PMID 16777543.
- Weinstein MC, Stason WB. "Hypertension: a policy perspective. Cambridge, Mass.: Harvard University Press, 1976.
- Weinstein MC, Stason WB (1978). "Economic considerations in the management of mild hypertension". Ann N Y Acad Sci. 304 (1): 424–440. Bibcode:1978NYASA.304..424W. doi:10.1111/j.1749-6632.1978.tb25625.x. PMID 101118.
- Taylor WC, Pass TM, Shepard DS, Komaroff AL. Cost effectiveness of cholesterol reduction for the primary prevention of coronary heart disease in men. In: Goldbloom RB, Lawrence RS, eds. Preventing disease: beyond the rhetoric. New York: Springer-Verlag, 1990:437-41.
- Goldman L, Weinstein MC, Goldman PA, Williams LW (1991). "Cost-effectiveness of HMG-CoA reductase inhibition for primary and secondary prevention of coronary heart disease". JAMA. 265 (9): 1145–1151. doi:10.1001/jama.265.9.1145.
- The Diabetes Prevention Program Research Group (2012). "The 10-Year Cost-Effectiveness of Lifestyle Intervention or Metformin for Diabetes Prevention". Diabetes Care. 35 (4): 723–730. doi:10.2337/dc11-1468. PMC 3308273. PMID 22442395.
- Gortmaker, Steven L.; Long, Michael W.; Resch, Stephen C.; Ward, Zachary J.; Cradock, Angie L.; Barrett, Jessica L.; Wright, Davene R.; Sonneville, Kendrin R.; Giles, Catherine M. (2015). "Cost Effectiveness of Childhood Obesity Interventions". American Journal of Preventive Medicine. 49 (1): 102–111. doi:10.1016/j.amepre.2015.03.032. PMID 26094231.
- Barrett, Jessica L.; Gortmaker, Steven L.; Long, Michael W.; Ward, Zachary J.; Resch, Stephen C.; Moodie, Marj L.; Carter, Rob; Sacks, Gary; Swinburn, Boyd A. (2015). "Cost Effectiveness of an Elementary School Active Physical Education Policy". American Journal of Preventive Medicine. 49 (1): 148–159. doi:10.1016/j.amepre.2015.02.005. PMID 26094235.
- Wright, Davene R.; Kenney, Erica L.; Giles, Catherine M.; Long, Michael W.; Ward, Zachary J.; Resch, Stephen C.; Moodie, Marj L.; Carter, Robert C.; Wang, Y. Claire (2015). "Modeling the Cost Effectiveness of Child Care Policy Changes in the U.S.". American Journal of Preventive Medicine. 49 (1): 135–147. doi:10.1016/j.amepre.2015.03.016. PMID 26094234.
- Black, Nicole; Johnston, David W.; Peeters, Anna (2015-09-01). "Childhood Obesity and Cognitive Achievement". Health Economics. 24 (9): 1082–1100. doi:10.1002/hec.3211. ISSN 1099-1050. PMID 26123250.
- Schmeiser, Maximilian D. (2012-04-01). "The impact of long-term participation in the supplemental nutrition assistance program on child obesity". Health Economics. 21 (4): 386–404. doi:10.1002/hec.1714. ISSN 1099-1050. PMID 21305645.
- Serdula, M. K.; Ivery, D.; Coates, R. J.; Freedman, D. S.; Williamson, D. F.; Byers, T. (1993-03-01). "Do Obese Children Become Obese Adults? A Review of the Literature". Preventive Medicine. 22 (2): 167–177. doi:10.1006/pmed.1993.1014. PMID 8483856.
- Cohen, Joshua. "The cost savings and cost-effectiveness of clinical preventative [sic] care. Robert Wood Johnson Foundation". THE SYNTHESIS PROJECT. Robert Wood Johnson Foundation. Retrieved March 24, 2016.
- Arenas, Daniel J.; Lett, Lanair A.; Klusaritz, Heather; Teitelman, Anne M.; van Wouwe, Jacobus P. (28 December 2017). "A Monte Carlo simulation approach for estimating the health and economic impact of interventions provided at a student-run clinic". PLOS ONE. 12 (12): e0189718. Bibcode:2017PLoSO..1289718A. doi:10.1371/journal.pone.0189718. PMID 29284026.
- Merkur, S., Sassi, F., & McDaid, D. (2013). Promoting health, preventing disease: Is there an economic case? European Observatory on Health Systems and Policies. Retrieved from http://eprints.lse.ac.uk/55659/
- David, McDaid; F., Sassi; Sherry, Merkur; iLibrary., OECD (June 2015). Promoting health, preventing disease: the economic case. ISBN 9780335262267. OCLC 973090310.
- Hackl F., Halla M., Hummer M., Pruckner G.J. (2015). "The Effectiveness of Health Screening" (PDF). Health Economics. 24 (8): 913–935. doi:10.1002/hec.3072. hdl:10419/115079. PMID 25044494.CS1 maint: multiple names: authors list (link)
- Partridge S., Balayla J., Holcroft C.A., Abenhaim H.A. (2012). "Inadequate Prenatal Care Utilization and Risks of Infant Mortality and Poor Birth Outcome: A Retrospective Analysis of 28,729,765 U.S. Deliveries over 8 Years". American Journal of Perinatology. 29 (10): 787–794. doi:10.1055/s-0032-1316439. PMID 22836820.CS1 maint: multiple names: authors list (link)
- Folland, S., Goodman, A., & Stano, M. (2013). The economics of health and health care. (7th ed.). Upper Saddle River: Pearson Education.
- American Hospital Association. (2015, Jan). The Promise of Telehealth for Hospitals, Health Systems and Their Communities. Retrieved from http://www.aha.org/research/reports/tw/15jan-tw-telehealth.pdf
- Robert Wood Johnson Foundation. (2009). The cost savings and cost-effectiveness of clinical preventive care. The Synthesis Project: New Insights from Research Results. Research Synthesis Report No. 18.
- Galama T. J., van Kippersluis H. (2013). "Health Inequalities through the Lens of Health-Capital Theory: Issues, Solutions, and Future Directions". Health Inequalities through the Lens of Health Capital Theory: Issues, Solutions, and Future Directions. Research on Economic Inequality. 21. pp. 263–284. doi:10.1108/S1049-2585(2013)0000021013. ISBN 978-1-78190-553-1. PMC 3932058. PMID 24570580.
- Centers for Disease Control and Prevention. (2013). Preventive Health Care. Retrieved from https://www.cdc.gov/healthcommunication/toolstemplates/entertainmented/tips/preventivehealth.html
- U.S. Preventive Services Task Force (USPSTF). (2017, Jan). USPSTF A and B Recommendations. Retrieved from https://www.uspreventiveservicestaskforce.org/Page/Name/uspstf-a-and-b-recommendations/
- U.S. Preventive Services Task Force (USPSTF). (2016, Dec). Reports to Congress. Retrieved from https://www.uspreventiveservicestaskforce.org/Page/Name/reports-to-congress
- Centers for Disease Control and Prevention. (2017, Feb. 27). Perinatal Quality Collaboratives. Retrieved from https://www.cdc.gov/reproductivehealth/maternalinfanthealth/pqc.htm
- Center for Connected Health Policy. The National Telehealth Policy Resource Center. Reports and Policy Briefs. Retrieved from http://www.telehealthpolicy.us/reports-and-policy-briefs
- Jensen G.A., Salloum R.G., Hu J., Ferdows N.B., Tarraf W. (2015). "A slow start: Use of preventive services among seniors following the Affordable Care Act's enhancement of Medicare benefits in the U.S". Preventive Medicine. 76: 37–42. doi:10.1016/j.ypmed.2015.03.023. PMID 25895838.CS1 maint: multiple names: authors list (link)
- Fein, Oliver (1 January 2010). "Keep the Single Payer Vision". Medical Care. 48 (9): 759–760. doi:10.1097/mlr.0b013e3181f28be4. JSTOR 25750554. PMID 20716995.
- Harrington, Scott E. (1 January 2010). "U. S. Health-care Reform: The Patient Protection and Affordable Care Act". The Journal of Risk and Insurance. 77 (3): 703–708. doi:10.1111/j.1539-6975.2010.01371.x. JSTOR 40783701.
- Rosenbaum, Sara (1 January 2011). "The Patient Protection and Affordable Care Act: Implications for Public Health Policy and Practice". Public Health Reports. 126 (1): 130–135. doi:10.1177/003335491112600118. JSTOR 41639332. PMC 3001814. PMID 21337939.
- Centers for Disease Control Prevention (1 January 2011). "Health Plan Implementation of U.S. Preventive Services Task Force A and B Recommendations — Colorado, 2010". Morbidity and Mortality Weekly Report. 60 (39): 1348–1350. JSTOR 23320884. PMID 21976117.
- Folland, S (2010). The economics of health and health care. Upper Saddle River: Pearson Education.
- "ACA: Preventive Care Coverage Requirements — Compliancedashboard: Interactive Web-Based Compliance Tool". complianceadministrators.com. Retrieved 2016-03-25.
- "Preventive Services Covered by Private Health Plans under the Affordable Care Act". kff.org. 2015-08-04. Retrieved 2016-03-25.
- "Preventative [sic] care services". UnitedHealthcare. Retrieved March 23, 2016.
- O'Grady, M. "Health-Care Cost Projections for Diabetes and other Chronic Diseases: The Current Context and Potential Enhancement" (PDF). Fight Chronic Disease. Retrieved March 24, 2016.
- "Estimating the Effects of Federal Policies Targeting Obesity: Challenges and Research Needs". Congressional Budget Office. Retrieved 2016-03-25.
- "A prevention prescription for improving health and health care in America" (PDF). Bipartisan policy center. Retrieved March 24, 2016.
- Milken Institute. (January 2014). Checkup Time, Chronic Disease and Wellness in America: Measuring the Economic Burden in a Changing Nation. Accessed 3/23/18 from http://assets1c.milkeninstitute.org/assets/Publication/ResearchReport/PDF/Checkup-Time-Chronic-Disease-and-Wellness-in-America.pdf
- Centers for Disease Control and Prevention. CDC National Health Report Highlights. Accessed 3/18/18 from https://www.cdc.gov/healthreport/publications/compendium.pdf
- Mokdad, Ali H. (10 March 2004). "Actual Causes of Death in the United States, 2000". JAMA. 291 (10): 1238–45. doi:10.1001/jama.291.10.1238. PMID 15010446.
- Centers for Disease Control and Prevention. (2017). Chronic Diseases Overview. Accessed 3/18/18 from https://www.cdc.gov/chronicdisease/overview/index.htm#ref2
- Healthy People 2020. Immunization and Infectious Diseases: Overview. Accessed 3/18/18 from https://www.healthypeople.gov/2020/topics-objectives/topic/immunization-and-infectious-diseases
- Jit, Mark; Hutubessy, Raymond; Png, May Ee; Sundaram, Neisha; Audimulam, Jananie; Salim, Safiyah; Yoong, Joanne (3 September 2015). "The broader economic impact of vaccination: reviewing and appraising the strength of evidence". BMC Medicine. 13 (1): 209. doi:10.1186/s12916-015-0446-9. PMC 4558933. PMID 26335923.
- "Economic Costs of Diabetes in the U.S. in 2012". Diabetes Care. 36 (4): 1033–1046. 6 March 2013. doi:10.2337/dc12-2625. PMID 23468086.
- Goettler, Andrea; Grosse, Anna; Sonntag, Diana (5 October 2017). "Productivity loss due to overweight and obesity: a systematic review of indirect costs". BMJ Open. 7 (10): e014632. doi:10.1136/bmjopen-2016-014632. PMC 5640019. PMID 28982806.
- Folland, S., Goodman, A.C., & Stano, M. (2016). Demand for Health Capital. The Economics of Health and Healthcare, 7th ed. (p. 130). New York, NY: Routledge.
- The Synthesis Project, Policy Brief No. 18. (September 2009). Cost savings and cost-effectiveness of clinical preventive care. Robert Wood Johnson Foundation. Accessed 3/18/18 from https://www.rwjf.org/content/dam/farm/reports/issue_briefs/2009/rwjf46045
- The Association of State and Territorial Health Officials. (2012). The economic case for health equity. Accessed 3/18/18 from http://www.astho.org/Programs/Health-Equity/Economic-Case-Issue-Brief/
- Colby, S.L., & Ortman, J.M. (March, 2015). Projections of the size and composition of the U.S. population: 2014-2060. United States Census Bureau: Current Population Reports, pp. 25-1143. Accessed 3/18/18 from https://census.gov/content/dam/Census/library/publications/2015/demo/p25-1143.pdf
- Centers for Disease Control and Prevention. (9 June 2016). Health in All Policies. Accessed 3/18/2018 from: https://www.cdc.gov/policy/hiap/index.html
- Centers for Disease Control and Prevention. (21 Oct 2016). Health Impact in 5 Years. Accessed 3/18/2018 from: https://www.cdc.gov/policy/hst/hi5/index.html
- Chriqui J.F. (2013). "Obesity prevention policies in U.S. states and localities: lessons from the field". Curr Obes Rep. 2 (3): 200–210. doi:10.1007/s13679-013-0063-x. PMC 3916087. PMID 24511455.
- City of Philadelphia. Bill No. 160176. Accessed 3/18/18 from https://beta.phila.gov/media/20170209150802/CertifiedCopy16017601-1.pdf
- Healthy Food Policy Project. (2017). Accessed 3/18/18 from http://healthyfoodpolicyproject.org/policy/philadelphia-penn-code-tit-chapter-19-4100-current-through-nov-7-2017
- Council for Better Business Bureaus, Inc. (2018). Accessed 3/18/18 from https://bbbprograms.org/programs/CFBAI/
- Frazier, W.C. & Harris, J.L. (June 2017). Trends in television food advertising to young people: 2016 update. Accessed 3/18/18 from http://www.uconnruddcenter.org/files/TVAdTrends2017.pdf
- Immunization Action Coalition. (2018). State mandates on immunization and vaccine-preventable diseases. Accessed 3/18/18 from http://www.immunize.org/laws/
- Centers for Disease Control and Prevention. (2018). Recommended immunization schedule for children and adolescents aged 18 years or younger, United States, 2018. Accessed 3/18/18 from https://www.cdc.gov/vaccines/schedules/hcp/child-adolescent.html
- Advisory Committee on Immunization Practices. Accessed 3/18/18 from https://www.cdc.gov/vaccines/acip/index.html