Development of a shoulder pain and disability index

A shoulder pain and disability index (SPADI) was developed to measure the pain and disability associated with shoulder pathology. The SPADI is a self-administered index consisting of 13 items divided into two subscales: pain and disability. Thirty-seven male patients with shoulder pain were used in a study to examine the measurement characteristics of the SPADI. Test-retest reliability of the SPADI total and subscale scores ranged from 0.6377 to 0.6552. Internal consistency ranged from 0.8604 to 0.9507. SPADI total and subscale scores were highly negatively correlated with shoulder range of motion (ROM) supporting the criterion validity of the index. Principal components factor analysis with and without varimax rotation supported the construct validity of the total SPADI and its subscales. High negative correlations between changes in SPADI scores and changes in shoulder ROM indicated the SPADI detected changes in clinical status over short time intervals. The SPADI should prove useful for both clinical and research purposes.