Psychometric properties of the TSK-11: a shortened version of the Tampa Scale for Kinesiophobia

Abstract

The Tampa Scale for Kinesiophobia (TSK) is one of the most frequently employed measures for assessing pain-related fear in back pain patients. Despite its widespread use, there is relatively little data to support the psychometric properties of the English version of this scale. This study investigated the psychometric properties of the English version of the TSK in a sample of chronic low back pain patients. Item analysis revealed that four items possessed low item total correlations (4, 8, 12, 16) and four items had response trends that deviated from a pattern of normal distribution (4, 9, 12, 14). Consequently, we tested the psychometric properties of a shorter version of the TSK (TSK-11), having excluded the six psychometrically poor items. The psychometric properties of this measure were compared to those of the original TSK. Both measures demonstrated good internal consistency (TSK: alpha=0.76; TSK-11: alpha=0.79), test-retest reliability (TSK: ICC=0.82, SEM=3.16; TSK-11: ICC=0.81, SEM=2.54), responsiveness (TSK: SRM=-1.19; TSK-11: SRM=-1.11), concurrent validity and predictive validity. In respect of specific cut-off scores, a reduction of at least four points on both measures maximised the likelihood of correctly identifying an important reduction in fear of movement. Overall, the TSK-11 possessed similar psychometric properties to the original TSK and offered the advantage of brevity. Further research is warranted to investigate the utility of the new instrument and the cut-off scores in a wider group of chronic pain patients in different clinical settings.