HIV intervention programs 8.2.2 Researchers Jemmott III et al. (Journal of American Medical Association, 1998) reported a study in which a group of inner-city African American adolescents from Philadelphia were randomly divided into three groups as part of an experiment to assess the effectiveness of different HIV prevention programs. One group was given "abstinence HIV intervention," the next group was given "safer-sex HIV intervention," and the third group was given "health promotion intervention," which was to serve as a control. One outcome that was measured was whether subjects who were sexually active during a three-month period reported consistent condom use. The 8.2.2A table shows the summarized data. 1. Is this an experiment or an observational study? How are you deciding? 2. Identify the observational units