Human subject screening: a dynamic process.

Abstract

INTRODUCTION: The history of disqualified (DQ) subjects from 1973-1993 at Armstrong Laboratory, Wright Patterson AFB, is presented for both sustained and impact acceleration panels. METHODS: Candidate and subject medical records were reviewed for screening results, recommendation for panel duty, and any follow-up medical findings. The generation and interpretation of the medical screening criteria and DQ rates are discussed. MEDICAL SCREENING CRITERIA: The mechanisms for change, those factors influencing change, and the interpretation of the screening criteria for Armstrong Laboratory's acceleration panels determine the panel's composition, which is reflected in the DQ rates. RESULTS: The centrifuge had a 5% (7/132) disqualification (DQ) rate from 1973-93 with 29% (2/7) due to musculoskeletal and 71% (5/7) for medical reasons. All were DQ during 1973-88. The impact panel had a DQ rate of 18% (36/195) with 71% (24/34) DQ due to musculoskeletal and 29% (10/34) for medical reasons. Only 28% (10/36) were DQ during 1973-88, while during 1989-93, 72% (26/36) were DQ. CONCLUSIONS: The differences in DQ rates between the centrifuge and impact facility were due to the variability or conservatism of individual physicians, interpretation of the medical screening criteria, and the type of research being done. These factors effect the composition of the human subject panels. This determines to which target population the research data can be applied. If the subjects do not represent pilots due to inappropriate screening, then there is no benefit from the research and, therefore, there can be no risk incurred by the subjects.