There are many terms and concepts involved in measuring the health status of a population. Chapter four provides you with many examples of the most common rates, ratios, and proportions used in epidemiology. For the healthcare administrator, it is important to understand these different measures of morbidity and mortality in order to make decisions that can impact determinants of health, access to care, and quality of care.

CompletebothCase Studies 4.1 and 4.2 in your textbook. Explain your answers in full sentences (i.e. do not just answer "yes" or "no").

Case Study 4.1: Example of Cumulative Incidence

It is well known that age is often associated with health outcomes. In a study of 36,711 patients aged 65 and older who had previously had a myocardial infection,* researchers examined the cumulative incidence of hospital readmission in the 1-year period after the initial episode of myocardial infection. They also examined the cumulative incidence of death in each age group in the 1-year period after the initial myocardial infection. TABLE 4.10 shows the cumulative incidence rates of overall hospital readmission as well as cause-specific hospital readmission whether related or unrelated to cardiovascular disease.

Non-ST-segment-elevation myocardial infection.

Questions:

1) In this study, what effect, if any, did age have on the cumulative incidence of death?

2) Did age have any effect on the overall and cause-specific cumulative incidence of hospital readmissions

3) Was there a noteworthy difference or pattern in the cumulative incidence rates for CVD-related and non-CVD-related (cause-specific) hospital readmissions?

Table 4.10: Cumulative incidence of hospital Readmission and Death Within 1 Year After the Initial/Index Episode

Age 65-79 Age 80-84 Age 85-89 Age 90

(n= 21,586) (n= 7,324) (n= 5,007) (n=2,794)

Overall readmissions 52.7% 59.6% 59.5% 59.5%

CVD8-unrelated readmissions 32.4% 38.4% 38.0% 34.5%

CVD*-related readmissions 38.4% 43.2% 43.2% 39.6%

MI/stroke* readmissions 8.6% 12.1% 13.6% 14.0%

Deaths 13.3% 23.6% 33.6% 45.5%

Case Study 4.2: Example of a Prevalence Study

This study compared the prevalence of current cigarette smoking in adult HIV patients receiving medical care with the prevalence in the general U.S. adult population. The researchers used data from two nationally representative cross-sectional surveys: A sample of 4, 271 adult HIV patients who participated in the Medical Monitoring Project, and a sample of 27,731 adults in the general population who participated in the National Interview Survey. The data on smoking were adjusted for the probability of being selected to participate in the survey, as well as for the non-response. Table 4.11 shows the adjusted prevalence of current smokers stratified by age, sex, race, education, and income.

Questions:

1) How did age, race, sex, and education affect smoking prevalence in HIV- and non-HIV- positive adults in this study?

2) What might explain higher smoking prevalence in HIV-positive adults in each demographic category of study participants?

Table 4.11: Adjusted Prevalence and Adjusted Prevalence Difference of Current Cigarette Smoking Among Adults with HIV Who Received Medical Care and the General Adult Population in the United States in 2009

Characteristic Adjusted Current Smoking Prevalence Adjusted Prevalence Difference

HIV Adults %(A) General Adult Population %(B) (A-B)

Total 37.6 20.6 17.0

Age

18-29 years 35.7 23.6 12.1

30-39 years 39.2 24.9 14.3