Many different study designs are used in epidemiological research. state which study design is being used in each of the scenarios described below. your choices are as follows:

*experimental study

*retrospective cohort study

*prospective cohort study

*case-control study

*cross-sectional study

*ecological study

a. a hospital-based study of antidepressant medication use during pregnancy and the risk of cleft lip in the offspring. investigators are currently enrolling two groups of women: those who just delivered an infant with a cleft lip and a sample of women who just delivered an infant without any birth defects. the presence or absence of birth defects is based on the newborn physical exam. all mothers are being interviewed to determine their use of antidepressant medications during the pregnancy that just ended.

According to the federal regulations, which of the following studies meets the definition of research with human subjects? a study of twenty 4th grade classrooms in which researchers ask the schools to systematically vary the time of day reading is taught, and collect weekly assessments of reading comprehension for each child over a three-month period.the collection of data, by a playground designer hired by the superintendent of schools, about the physical dimensions of school playgrounds, presence of fencing, and the kinds of equipment currently provided.a feasibility study for implementing a year-round school program, focusing on economic issues such a facilities utilization and transportation costs.an analysis of aggregate data comparing statewide high school graduation rates provided by the state department of public instruction, using county tax information.