A Benchmark Analysis for Personality Disorder Research: Studies Using Clinicians

Prototype studies often involve using clinicians as subjects. Clinician sampling is a consistent methodological issue in these studies. Studies using clinicians recruited by mail often have low return rates (approximately 25%). The self-selection bias associated with clinicians who volunteer to participate in these studies is unknown. To analyze the effect of a self-selection bias, a benchmark study was performed. Two groups of clinicians were randomly selected from psychiatrists and psychologists who were listed in the yellow pages of the 50 most populous cities in the United States. For one group, clinicians were asked to volunteer; in the other group, clinicians were paid $100 each for participating. The return rate for volunteer clinicians was 15% while the return rate for paid clinicians was 67%. No differences were found between the two groups in terms of demographic characteristics nor were there major differences in their diagnoses of 20 case histories.