If we want more evidence-based practice, we need more practice-based evidence.*
Table of Contents
The objective in this chapter is to introduce two more of the foundation sciences of community and population health: demography and epidemiology. Demography provides the concepts and measurements of human population dynamics, and epidemiology relates these tools to the analysis of the causes, transmission and distribution of disease and health conditions. When analyzing community health issues, it is important for you to look deeper than averages or data for the total population; instead, explore subgroups differences, such as differences found by gender, class, and race. Asking what works in community health is not as revealing a question as asking what works for whom and under what circumstances.
These two foundation sciences are described with examples of the community and population health applications and implications. Basic rates and other formulas for the measurement of health in populations and the epidemiological triad of host, agent and environment are explained. Examples of the major biological and social risk factors accounting for premature death or the difference between life span and life expectancy are described. These include both modifiable and unmodifiable risk factors included in the calculation of years of productive life lost. Most of the modifiable risk factors require community action and lifestyle or behavioral changes, which lead us into the next chapter.
Morbidity & Mortality Weekly Reports, January 14, 2005
Journal of the American Medical Association (291(10):1238-45), 2004. CDC
Census Bureau Says Median Age is 35.WASHINGTON (AP, June 15, 1999) – The median age of Americans in 1998 reached a record high of 35.2 years, according to population estimates released Monday by the US Census Bureau. AP story at: http://www.applesforhealth.com/HealthyFeatures/wegeto2.html. For the Census Bureau report, go to: http://www.census.gov.
Kaiser Family Foundation to Launch Native American Health Policy Fellowship Program.The Henry J. Kaiser Family Foundation has announced a new health policy fellowship program designed to give Native American health and welfare leaders an opportunity to learn more about national policy issues that affect the health and welfare of Native American communities and gain a better understanding of the national policymaking process. The fellowships began in January 1999 and are administered by the First Nations Development Institute http://www.firstnations.org.
Disease Crisis Looming, According to WHO Report (The Independent, May 20, 1996) Fatal complacency is allowing diseases such as malaria and Tuberculosis, once thought to be subdued, to resurge, killing millions of people each year.
Vital Statistics to Leave Out Marital Status (Canadian Press July 4, 1996) Marriages are becoming less important as a vital statistic as common-law arrangements are taking a greater role in "family life".
Funds for Population Battle Decline, (Canadian Press July 9, 1996) Several western nations are not living up to the commitments made at the 1994 Cairo Conference on World Population. The key goal of the conference was to increase funds for educating women. Educated women have fewer children.
CENSUS 2000 Makes Headlines
In another blow for science, the Federal Court rejected the call to use sampling methods in conducting the 2000 Census, in favor of the traditional process of enumerating every person census-takers can find. Despite a Congress-commissioned National Academy of Sciences report which stated that "sampling was the only way to ensure an accurate count;" despite the endorsement of essentially every scientific organization that chose to weigh in; and despite President Clinton's strong support, the Court ruled that the government must follow the letter of the original law.
The debate had been highly political, with the Republican Congress pushing hard for enumeration. Census stakeholders cite Census Bureau and GAO findings that the 1990 Census undercounted the population by an estimated 10 million people, most of whom were Hispanics or African-Americans, about half children. Many stakeholders feel that Republicans oppose sampling because undercounted groups often vote Democratic, and because their numbers could contribute to congressional redistricting and redistribution of funds for public services and schools.
For information: The Census 2000 Initiative has a comprehensive website that posts fact sheets, news alerts, links, and more.http://www.census2000.org House Subcommittee on the Census: http://www.house.gov/danmiller/census/
For a tutorial slide presentation on how to obtain and use data from the US Census Bureau, go to:http://www.siu.edu/~kittle/HEDIR/state/
For a tutorial on accessing US, State, and county statistics through the CDC Wonder site, go to:http://www.siu.edu/~kittle/HEDIR/state/
For a list of other web sites for demographic and census sources, go to:
For related news stories, pleaseclick here.
Aspinall, P.J. (1999). For debate. Ethnic groups and Our Healthier Nation: whither the information base? JOURNAL OF PUBLIC HEALTH MEDICINE 21(2): 125-132. For abstract, go to:http://www.oup.co.uk/pubmed/hdb/Volume_21/Issue_02
Benichou, J., Chow, W-H., Fraumeni Jr., J. F. (1998). Population Attributable Risk of Renal Cell Cancer in Minnesota. AMERICAN JOURNAL OF EPIDEMIOLOGY 148 (5): 424.
Collins, S. E., Haining, R. P., Bowns, I. R., Crofts, D. J., Williams, T. S., Rigby, A. S., & Hall, D. M. B. Errors in postcode to enumeration district mapping and their effect on small area analyses of health data. JOURNAL OF PUBLIC HEALTH MEDICINE 20(3): 325-330. For the abstract, go to:http://www3.oup.co.uk/pubmed/hdb/Volume_20/Issue_03/200325.sgm.abs.html and for other titles/abstracts in this issue, go to: http://www.oup.co.uk/pubmed/hdb/Volume_20/Issue_03/ .
Dinse, G. E., Umbach, D. M., Sasco, A. J., Hoel, D. G., & Davis, D. L. (1999). Unexplained Increases in Cancer Incidence in the United States from 1975 to 1994: Possible Sentinel Health Indicators. ANNUAL REVIEW OF PUBLIC HEALTH 20: 173-210. Abstract/FullText: Abstract.
Ellison, L. F., Morrison, H. I., de Groh, M., Villeneuve, P. J. (1999). Short Report. Health consequences of smoking among Canadian smokers: An update. CHRONIC DISEASES IN CANADA 20 (1): 36-39. FULL-TEXT/Abstract:http://www.hc-sc.gc.ca/main/lcdc/web/publicat/cdic/cdic201/cd201f_e.html
Eyers, J. E. (1998). How to do (or not to do) . . . searching bibliographic databases effectively. HEALTH POLICY & PLANNING 13(3):339-342.
Hartog, J., Oosterbeek, H. (1998). Health, wealth, and happiness: Why pursue a higher education? ECONOMICS OF EDUCATION REVIEW 17 (3): 245-256.
Hunt-Mccool, J., & Bishop, D.M. (1998). Health economics and the economics of education: Specialization in the division of labor. ECONOMICS OF EDUCATION REVIEW 17 (3): 237-244.
Jones, K., & Klein, H. (1999). Lessons from 12 Years of Comparative Risk Projects. ANNUAL REVIEW OF PUBLIC HEALTH 20: 159-172.
Kahn, M. E. Education's role in explaining diabetic health investment differentials. ECONOMICS OF EDUCATION REVIEW 17 (3): 257-266.
Kaplan, G. A., Haan, M. N., & Wallace, R. B. (1999). Understanding Changing Risk Factor Associations with Increasing Age in Adults. ANNUAL REVIEW OF PUBLIC HEALTH 20: 89-107.
Kiker, B. F. Introduction to special issue on education and health. ECONOMICS OF EDUCATION REVIEW 17 (3):233-235.
Moloo, J., Jackson, K. L., Waller, J. L., McKeown, R. E., Addy, C. L., Cuffe, S. P., Garrison, C. Z. (1998). Xenotransmission of the socioeconomic gradient in health? A population based study. BRITISH MEDICAL JOURNAL 317:1686-1686.
Saunders, J. (1998). Weighted census-based deprivation indices: Their use in small areas. JOURNAL OF PUBLIC HEALTH MEDICINE 20(3): 253-260. For the abstract, go to:http://www3.oup.co.uk/pubmed/hdb/Volume_20/Issue_03/200253.sgm.abs.html and for other titles/abstracts in this issue, go to: http://www.oup.co.uk/pubmed/hdb/Volume_20/Issue_03/ .
Schwartz, S., Susser, E., & Susser, M. (1999). A Future for Epidemiology? ANNUAL REVIEW OF PUBLIC HEALTH 20: 15-34.
Walter, S. D. (1998). Attributable Risk in Practice. AMERICAN JOURNAL OF EPIDEMIOLOGY 148 (5): 411.
Wood, D., Saarlas, K. N., Inkelas, M., and Matyas, B. T. (1999). Immunization Registries in the United States: Implications for the Practice of Public Health in a Changing Health Care System. ANNUAL REVIEW OF PUBLIC HEALTH 20: 231-256.
Yen, I., & Syme, S. L. (1999). The Social Environment and Health: A Discussion of the Epidemiologic Literature. ANNUAL REVIEW OF PUBLIC HEALTH 20: 287-308.
Books and Reviews
Young, T. Kue. Population Health: Concepts and Methods. New York: Oxford University Press, 1998. ISBN 0-19-511972-X.
Australian Institute of Health and Welfare. Australia's Health 1998.
Kuo, J. (1998). Health status of Asian Americans: United States, 1992-94. Advance data from vital and health statistics; no. 298. Hyattsville, Maryland: National Center for Health Statistics.
Pamuk, E., Makuc, D., Heck, K., Reuben, C., Lochner, K. (1998). Socioeconomic Status and Health Chartbook. Health, United States, 1998. Hyattsville, MD: National Center for Health Statistics.
Statistics Canada report on the 1996-97 Population Health Survey
Ziglio, E. and Harrison, D. (Eds). The Social determinants of health: Implications for the health professions. National Academy of Medicine, Rome, Italy in 'Forum: Trends in Experimental and Clinical Medicine, 8.3 Suppl. n.4.
1. The Tragedy of the commons. This box provides an understanding of the issues involved when dealing with population growth and limited resources. It speaks to short and long term goals, exploitation of resources and health outcomes for communities. Can you provide an example of resource use in your community that deals with the issues discussed here?
2. Rates and numbers for AIDS infection. Review Figure 3-9. Discuss the marked difference between prevalence rates in other countries and those of the United States. Does the US have that much of a greater AIDS problem or is it a matter of more accurate surveillance systems? Graph B shows the incidence rates (new cases) in Canada. Discuss the difficulties in obtaining accurate incidence rates for a disease like AIDS.
3. Percentage of population at a given age. Review Figure 3-11. As the proportion of the population over 65 years continues to grow, what implications are there on the health care systems currently in place and on health care costs in general?
4. Diseases targeted by WHO for eradication or elimination. How realistic is it to eradicate diseases on a global scale? What are some of the barriers that may prevent the successful eradication of these diseases?
5. Premature deaths in two age groups. Review Figure 3-15. It is evident that adults have a substantially different set of root causes for premature death than the 5-24 age group. In which group do you think prevention strategies likely to be more effective? How do these data vary by gender, class, and race?
6. History. John Graunt of England is credited with beginning demography as a science in the 17th century. He constructed the first mortality table. By analyzing birth and death rates in London, he also was able to estimate roughly the number of men currently of military age, the number of women of childbearing age, the total number of families, and the size of the city's population. Examine a mortality table and discuss how demographic projections are made.
7. Vital statistics of whites and blacks. Historically, there have been noticeable differences in life expectancy at birth for North Americans by gender and race. Why do white females have the longest expected life span and black males the shortest (and decreasing in recent years)? Why does Japan lead the world in longevity for both males (75.9 years) and females (81.8 years)?