1) Researchers in South Africa were interested in prevalence ofHIV-related behaviors and infection in the population. Theyadministered a survey of 500 men and women who came for health careat a hospital clinic in Johannesburg. At the same time, allsubjects were tested for HIV status. Prevalence of HIV was higherin men than in women. Men were also more likely to use IV drugs andto engage in sex with multiple sex partners. What type of studydesign is this?
2)
Investigators interested in whether maternal-fetal sharing ofHLA genes was associated with preeclampsia identified recent birthsfrom state birth certificate files. They selected all women whosebirth certificate indicated preeclampsia in pregnancy and a randomsample of women for whom preeclampsia was not indicated on thebirth certificate. After confirming preeclampsia status in medicalrecords, a total of 250 women with preeclampsia and a similarnumber of women without preeclampsia were enrolled. All womenprovided buccal cell samples from themselves and their babies forHLA-typing. Maternal-fetal sharing was more common among women withpreeclampsia than women without preeclampsia. What type of studydesign is this?