Responsiveness and minimal clinically important changes for the Tampa Scale of Kinesiophobia after lumbar fusion during cognitive behavioral rehabilitation

BACKGROUND: The Tampa Scale of Kinesiophobia (TSK) is a commonly-used measure for the assessment of fear of movement beliefs in chronic complaints, but its responsiveness in subjects after lumbar fusion has been never reported. AIM: Evaluating the responsiveness and minimal clinically important differences (MCIDs) for the TSK and its subscales after lumbar fusion. DESIGN: Population-based cohort study. SETTING: Secondary care rehabilitation hospital. POPULATIO N: In-patients undergoing rehabilitation after lumbar fusion. METHODS: At the beginning and end of a four-week motor and cognitive-behavioral rehabilitation program, 180 patients completed the TSK. After the intervention, the global perceived effect (GPE) was analyzed to produce a dichotomous outcome (improved vs. stable). Responsiveness for the TSK and its subscales were calculated by distribution (effect size [ES], standardized response mean [SRM]) and anchor-based methods (receiver operating characteristics (ROC) curves; correlations between change scores of the TSK and its subscales and GPE). ROC curves were also used to compute MCID values. RESULTS : The ES ranged from 1.63 to 1.77 and the SRM from 1.25 to 1.39 for TSK and its subscales. The ROC analyses revealed a value of area under the curve (0.999 [95% CI : 0.978; 1.000], 0.998 [95% CI : 0.975; 1.000], 0.990 [95% CI: 0.962; 0.999] for the TSK, Harm and Activity Avoidance subscales, respectively). MCID values greater than 6 (95% CI: >5; >6), 4 (95% CI: >3; >5), and 2 (95% CI: >2; >2) were achieved for the TSK, Harm and Activity Avoidance subscales, respectively. Correlations between change scores of the TSK and its subscales and GPE were high (0.786-0.830). CONCLUSIONS: The TSK and its subscales were sensitive in detecting clinical changes in subjects undergoing rehabilitation after lumbar fusion. CLINICAL REHABILITATION IMPACT : The obtained MCID values will help in the design of future randomized controlled trials and in the interpretation of the clinical impact of a rehabilitation program after lumbar fusion.