Use of telephone screens improves efficiency of healthy subject recruitment.

Previous reports have indicated that a high percentage of those responding to advertisements for healthy controls for psychiatric research have personal or family histories of illness which would exclude them from such studies. We reviewed 1757 telephone screen interviews conducted over 14 years to determine: (1) the effectiveness of a screen for excluding unhealthy volunteers, (2) whether the reasons for exclusion changed over time, and (3) the final yield of healthy participants for psychiatric research after taking account of exclusions from telephone screens, no-shows and exclusions identified by direct interviews. Volunteers for psychiatric research, solicited by 43 newspaper advertisements in the Baltimore metropolitan area from 1989-2002, were initially screened by telephone and scheduled for in-person interviews if no exclusions were identified at the initial screen. More than half of the telephone respondents had major medical illnesses, substance abuse problems, depression, an Axis I disorder (not depression), a relative with a psychotic disorder or were otherwise deemed not eligible for face-to-face interview. Of the telephone respondents scheduled for direct interviews, 29% did not show up. However, the respondents who completed the direct interviews had a high likelihood of inclusion as non-ill controls for psychiatric research studies. Since Axis I and II interviews and family history take approximately 4-5 h per subject, the telephone screen is a cost-effective initial step in identifying healthy controls for psychiatric research.