This project will investigate the extent of sex bias in selection of research subjects in biological and behavioral research. For animal studies, scientific journals will be surveyed and data coded to determine the number of single sex studies, sex- comparative studies, observed sex differences and where generalization of research findings occurred from single-sex studies to the opposite sex of the same or other species without apparent justification. Then, the extent of sex bias in clinical research with human subjects will be documented through a similar survey of clinical research journals. This inquiry will focus on four major disorders affecting men and women: AIDS/HIV infection, concer, coronary heart disease, and depression. Once relevant human studies have been identified, the investigators will look back to the animal experiments on which the clinical tests and trials were based, to determine if sex differences were studied or whether generalizations were made from single sex animal studies. This investigation would identify the extent, nature, and appropriateness of generalizing research findings from single sex studies and ultimately stimulate awareness of the problems inherent in generalization and of the need for rigorous sex-comparative research. The investigators and advisors are well qualified; the project plan is good; the budget is very reasonable; results are likely to have intellectual and practical significance. The proposal is recommended for support with high priority.