Discordance between the SCL-90 and therapists' psychopathology ratings.

This study examines the symptom checklist 90 (SCL-90), a patient self-report rating scale, as a screening and baseline psychopathology measure in an outpatient clinic. A low correlation (r = .17) was found between the SCL-90 and the SCL analogue, a matched psychopathology instrument rated by clinicians. The most common causes of discordance in ratings were patients' underreporting of symptoms due to patients' paranoia or fearfulness, overreporting of symptoms consistent with patients' "demonstrative" style, and false-positive items related to patients' physical illness. We conclude that the SCL-90 has limited validity as a clinical measure in the study of patients seen in evaluation in our setting.