Idiographic outcome analyses of the clinical significance of two interventions for patients with musculoskeletal pain

This study adopted a perspective of the individual to define domains of everyday life for the analysis of clinically meaningful change. The purpose was to compare the clinical significance of two interventions for patients with musculoskeletal pain, applying an idiographic outcome measure, The Patient Goal Priority Questionnaire, in combination with the Jacobson and Truax methodology [(1991). Clinical significance: A statistical approach to defining meaningful change in psychotherapy research. Journal of Consulting and Clinical Psychology, 67 (3), 300-307] for determination of clinical significance. The concurrent validity of the outcome variables behavioral performance, satisfaction with behavioral performance, and fulfilled pretreatment expectations was also studied. Eighty-two patients, randomized to either individually tailored behavioral medicine treatment (experimental group) or physical exercise therapy (control group) were evaluated at baseline and 3 months post-treatment regarding behavioral treatment goals. The experimental intervention had high impact on participants' performance of their highest ranked everyday life activities, and resulted in larger proportions of clinically significant outcomes compared with controls. The concurrent validity of the outcomes was high for those reporting clinically significant changes, but more generally, there was a moderate agreement across outcome categories. The individual should be the unit for analyses of clinical significance to enhance the ecological validity of the construct. Further development of idiographic outcome measures is necessary, as is the inclusion in pain intervention research. Keywords: Treatment outcome; Pain; Clinical significance; Behavioral medicine