3. To evaluate the convergent validity of four decision rules for concluding that a patient with TTM has benefited sufficiently from a treatment step: (a) No longer meeting TTM diagnostic criteria; (b) Showing a 25% or greater reduction in total scores on self-report and clinician-rated TTM symptoms; (c) achieving complete abstinence from hair-pulling; and (d) clinically significant response on both self-report and clinician-rated TTM symptom measures