Change in Health-Related Quality-of-Life at Group and Individual Levels Over Time in Patients Treated for Chronic Myofascial Neck Pain

Abstract

Background. This study evaluated change in health-related quality of life at the group and individual levels in a consecutive series of patients with chronic myofascial neck pain. Methods. Fifty patients with chronic neck pain self-administered the Short Form-36 Version 2 (SF-36 v2) before treatment and 6 weeks later. Internal consistency reliability was estimated for the 8 scale scores and Mosier’s formula was used to estimate reliability of the physical and mental health composite scores. Significance of group-level change was estimated using within-group t statistics. Significance of individual change was evaluated by reliable change index. Results. Statistically significant ( P < .05) group mean improvement over time was found for all SF-36 scores. At the individual level, 20% of the possible changes were statistically significant (17% improvement, 3% decline). Conclusions. Estimating the significance of individual change in health-related quality of life adds important information in comparing different treatment modalities for chronic myofascial neck pain.