Toward a taxonomy of adolescents with chronic pain: Exploratory cluster and discriminant analyses of the bath adolescent pain questionnaire

Emerging evidence has indicated that adolescent chronic pain is a significant healthcare issue, the impact of which is determined by a complex interplay of biological, emotional, social, and familial factors. Recently, progress has been made in assessment of pain and functioning in adolescents with chronic pain. A next step is to evaluate whether discrete subgroups of patients exist and whether assessment measures can be used to determine subgroup membership for individual pain sufferers. The present study sought to address these two issues. A battery of questionnaires, including the bath adolescent pain questionnaire, was completed by 209 adolescents with chronic pain presenting for an assessment appointment. Results from cluster analyses indicated the presence of four distinct subgroups. Three clusters differed from one another along a single continuum of severity and the fourth was characterized by good family cohesion, moderate emotional difficulties, and significant difficulties with physical functioning. Follow-up analyses indicated significant differences among the clusters across eight of nine measures of functioning including pain intensity, healthcare utilization, school attendance, amount of weekly exercise, depression, disability, social functioning, and catastrophic thinking. A discriminant analysis was able to correctly classify over 95% of participants into the correct cluster. These results provide strong support for the derived four cluster solution, which may be useful in both clinical and research settings, as it allows for individual adolescent pain sufferers to be classified into groupings according to the severity and type of difficulties being experienced.