Measures of Disease Frequency

Informatics in Health Care

Community Health

Environmental Health

Global Health

Healthy Policy and Management

Health Promotion and Communication

Maternal and Child Health

Minority Health and Health Disparities

World Health Organization


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Global Disease Data


Many of the ethical issues of public health are matters of policy. However, public health intersects with clinical care at several points. The protection of the public from communicable diseases, for example, is occasionally in conflict with the medical duty of confidentiality. One aspect of public health, the immunization of children, is a particular issue for pediatric ethics.

Study Questions

Which preventative intervention leads to the largest average increase in life expectancy for a target population?

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The correct answer is B. You answered B.

The answer is B. Predicted increases in life expectancy are average numbers that apply to populations, not individuals. Because we often do not understand the true nature of risk of disease, screening and lifestyle interventions usually benefit a small proportion of the total population. For screening tests, false positives may also increase the risk of diagnostic tests. While Pap smears increase life expectancy overall by only 2–3 months, for the individual at risk of cervical cancer, Pap smear screening may add many years to life. The average life expectancy increases resulting from mammography (1 month), PSA (2 weeks), or exercise (1–2 years) are less than from quitting smoking (3–5 years).

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Herd Immunity


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