Which study design would you choose to employ in each of the following scenarios? answer choices include: prospective cohort study, retrospective cohort, case-control, cross-sectional, and clinical trial. include in your answer if the study design you choose is a descriptive or analytic study design.
(1) you would like to assess the effectiveness and efficiency of delivering health services through your clinic. after selecting a 20% sample of all patient visits during the past six months, you are able to characterize the patient population who used your clinic in terms of age, race, sex, method of referral, diagnostic category, therapy provided, and method of payment.
(2) you are interested in finding out whether middle-aged men who have irregular heartbeats are at greater risk of developing a heart attack than men whose heartbeats are regular. electrocardiogram (ecg) examinations are performed on all male office employees 35 years of age or older who work for texas health resources (thr) in tarrant county and use thr health services. the ecg exam results are classified as irregular or regular. eight years later, myocardial infarction rates are compared between those with and those without baseline ecg irregularities.
(3) to test the efficacy of a liquid vitamin d supplement in preventing cancer, study participants are randomly assigned to one of two groups: one in which 1000 mg of liquid vitamin d is administered daily, and one in which a liquid placebo is administered daily. both groups are followed for 15 years to determine the occurrence of cancer.
(4) the physical examination records of the incoming freshmen class of 1960 at the university of texas at arlington are examined in 2000 to see whether their recorded height and weight at the time of admission to the university are related to their chance of developing coronary heart disease by 2000.
(5) the entire population of women over age 60 in a given community is examined, and all who are determined to be free from having osteoporosis are questioned extensively about their diets. these women then are followed for several years to see whether or not their eating habits will predict their risk of developing osteoporosis.
(6) men and women are identified who developed a rare form of lung cancer in their 30s. the type of cancer is hypothesized to be associated with asbestos. the participants are asked about the different places they have lived, worked and gone to school over the past 25 years. state environmental records showing asbestos removal and asbestos control are then cross-referenced with the places identified by each study participant to find for which locations asbestos is recorded.