Information disclosure, subject understanding, and informed consent in psychiatric research

Investigator information disclosure and subject understanding are examined in four psychiatric studies using data drawn from observation of 88 consent sessions. In an attempt to determine if subjects' understanding of research can be improved, three experimental methods of information giving (including the use of independent subject educators) are compared to standard investigator disclosure. Findings indicate that the use of experimental techniques generally increases the quality of information delivered to prospective subjects, with disclosures by subject educators generating the most complete information. Subject understanding was also found to be significantly associated with the quality of information provided. Diagnosis and level of psychopathology, however, were found to be the most important predictors of subject understanding, with schizophrenics and the highly impaired most likely to demonstrate poor comprehension. These results suggest that the degree of improvement in understanding obtainable for severely disordered subjects is substantially lower than it is for others. The implications of these findings for informed consent, the regulation of medical research, and the protection of human subjects are discussed.