The properties of self-report research measures: beyond psychometrics

Self-report measures pertinent for personality disorder are widely used and many are available. Their relative merits are usually assessed on nomothetic psychometrics and acceptability to users is neglected. We report reactions of lay, patient and professional groups to the Personality Diagnostic Questionnaire (PDQ-IV); Millon Clinical Multiaxial Inventory (MCMI-III); the Borderline Syndrome Index (BSI); Rosenberg's Self-Esteem Scale (RSE) and the Social Functioning Questionnaire (SFQ). These were sent to 148 professionals, ex-patients and lay people for comment. Thirty-six per cent were returned. Pattern-coding by three raters revealed problematic themes across all measures, including inappropriate length, vague items and language, cultural assumptions and slang, state-bias and response-set. Measures can be depressing and upsetting for some participants (both patients and non-patients), hence administration of measures should be sensitive. Treatment may make people more self-aware, which may compromise validity for outcome research. This evaluation raises issues and concerns, which are missed in traditional psychometric evaluation.