The American Shoulder and Elbow Surgeons score highly correlates with the Simple Shoulder Test

Abstract

There is no consensus to which patient-determined shoulder outcome scores should be considered when analyzing patient outcomes for either clinical or research purposes. The use of multiple outcome scores may be redundant and cause increased responder burden. The hypothesis of this study is that the American Shoulder and Elbow Surgeons score (ASES) will highly correlate with the Simple Shoulder Test (SST) for rotator cuff repair and total shoulder arthroplasty and have comparable responsiveness. If determined to be highly correlated, the use of these scores simultaneously may be redundant and one score may be eliminated. A retrospective review of the senior author's database of patients undergoing rotator cuff repair and total shoulder arthroplasty was reviewed in which the ASES was recorded simultaneously with the SST. Correlations were determined using the Pearson correlation coefficient (r > 0.7 excellent; r = 0.61-0.7 strong-moderate; r = 0.31-0.6 moderate; r = 0.2-0.3 poor) for all interactions between the 2 scores. Subgroup analysis was performed to determine if correlations differed in (1) preoperative outcome and (2) postoperative outcome determinations. Responsiveness was determined by calculating the standardized response meanand the effect size of both scores. There were a total of 1810 simultaneous measurements (both rotator cuff repair and total shoulder arthroplasty) of the ASES and SST. The correlation was excellent for the ASES and SST for all patients (n = 1810; r = 0.81; P < .0001). The correlation of preoperative scores was strong-moderate (n = 1191; r = 0.60; P < .0001), and the correlation of postoperative scores was excellent (n = 619; r = 0.78; P < .0001). Both scores were determined to be highly responsive, but both the standardized response mean (2.8 vs. 2.1) and the effect size (2.2 vs. 1.8) of the ASES were greater than those of the SST. In general, there was an excellent correlation between the ASES and the SST for all patients undergoing arthroscopic rotator cuff repair and total shoulder arthroplasty. Because there is an excellent correlation between the 2 scores, including these 2 scores simultaneously in tracking patient-determined outcomes appears to be redundant and therefore unnecessary. Because there is superior responsiveness of the ASES score compared with the SST, the authors recommend utilization of the ASES over the SST in patients undergoing rotator cuff repair and total shoulder arthroplasty.