Preliminary examination of a proposed treatment-based classification system for patients receiving physical therapy interventions for neck pain

Background and Purpose Neck pain frequently is managed by physical therapists. The development of classification methods for matching interventions to subgroups of patients may improve clinical outcomes. The purpose of this study was to describe a proposed classification system for patients with neck pain by examining data for consecutive patients receiving physical therapy interventions. Subjects and Methods Standardized methods for collecting baseline and intervention data were used for all patients receiving physical therapy interventions for neck pain over 1 year. Outcome variables were the Neck Disability Index (NDI), numeric pain rating, and number of visits. Treatment was provided at the discretion of the physical therapist. After the completion of treatment, each patient was classified by use of baseline variables. The interventions received by the patient were categorized as being matched or not matched to the classification. Outcomes for patients who received matched interventions were compared with those for patients who received nonmatched interventions. The interrater reliability of the classification algorithm was examined with a subset of 50 patients. Results A total of 274 patients were included in this study (74% women; age [(X) over bar +/- SD]=44.4 +/- 6.0 years). The most common classification was centralization (34.7%); next were exercise and conditioning (32.8%) and mobility (17.5%). The interrater reliability for classification decisions was high (kappa=.95, 95% confidence interval [CI]=0.87-1.0). A total of 113 patients (41.2%) received interventions matched to the classification. Receiving matched interventions was associated with greater improvements in the NDI (mean difference=5.6 points, 95% CI=2.6-8.6) and in pain ratings (mean difference=0.74 point, 95% CI=0.21-1.3) than receiving nomnatched interventions. Discussion and Conclusion The development of classification methods for patients with neck pain may improve the outcomes of physical therapy intervention. This study was done to examine a previously proposed classification system for patients receiving physical therapy interventions for neck pain. Receiving interventions matched to the classification system was associated with better outcomes than receiving nonmatched interventions. Although the design of this study prohibited drawing conclusions about the effectiveness of the system, the results suggest that further research on the system may be warranted.