The inmates involved in the study were admitted from November 3, 1970, through November 2, 1972. The study compared the 476 inmates who reported to sick call four or more times (frequent users) in the course of their confinement with the 534 others who never reported (nonusers). The groups did not differ in mean age or education, but consistent with previous studies, there was a significantly high proportion of blacks among the frequent users. On the Minnesota Multiphasic Personality Inventory and the State Trait Anxiety Inventory, the frequent users had significantly higher scores on a number of scales that indicated they suffered from more anxiety and psychological distress and were more inclined to somaticize; however, there were no differences on the California Psychological Inventory which assesses aspects of normal, everyday functioning rather than psychiatric symptoms. Interview and case history data showed the frequent users had more previous health and substance abuse problems and that they reported having more nurturing, but not more cohesive, families. Implications for various theories of sick-call use are discussed. 4 tables and 35 references