The motor agitation and retardation scale: item analysis and inter-rater reliability

The extent to which objective motor disturbance contributes to “psychomotor” phenomena in depression is largely undetermined. As part of a larger project examining the clinical and neurophysiologic significance of psychomotor abnormalities in depression, the Motor Agitation and Retardation Scale (8 agitation and 9 retardation items) was developed. Eighty-four pretreatment medication-free inpatients who met either Research Diagnostic or DSM-III-R criteria for major depressive disorder were assessed, and 30 of these inpatients were co-rated by a clinical research worker for the inter-rater reliability substudy. Consistent with past reports, most manifestations of motor agitation and retardation achieved acceptable inter-rater reliability (mean = 0.80). However, the anchor system used in the past to rate motor symptoms, and employed here, only marginally captured the range of motor symptoms, as evidenced by the consistently skewed item score distributions. Item-total correlations were normally distributed within a narrow range, however principal components analysis accounted for only 34% (retardation) and 11% (agitation) of the score variances. An examination of individualsʹ scores revealed that while 70% of patients manifested some form of agitation or retardation, 80% of these patients manifested 4 or fewer motor symptoms, and the combinations of motor anomalies across individuals differed markedly. Additional analyses revealed the agitation and retardation symptoms that were most associated with independent rater judgments of HRSD agitation and retardation items. We conclude that motor agitation and retardation in depression are not globally manifested syndromes. Accurate clinical assessment of psychomotor agitation and retardation, typically dependent upon single-item ratings, may instead require multi-dimensional evaluation.