Reliability and Validity of the English Version of the AOSpine PROST (Patient Reported Outcome Spine Trauma)

STUDY DESIGN. Multicenter validation study. OBJECTIVE. The aim of this study was to translate and adapt the AOSpine PROST (Patient Reported Outcome Spine Trauma) into English, and test its psychometric properties among North-American spine trauma patients. SUMMARY OF BACKGROUND DATA. In the absence of an outcome instrument specifically designed and validated for traumatic spinal column injury patients, it is difficult to measure the effect size of various treatment options. The AOSpine Knowledge Forum Trauma initiated a project and developed the AOSpine PROST consisting of 19 items. METHODS. Patients were recruited from two level-1 North-American trauma centers. For concurrent validity, next to AOSpine PROST also 36-item Short-Form Health Survey (SF-36) was filled out by patients. Patient characteristics were analyzed using descriptive statistics. Floor and ceiling effects as well as the number of inapplicable and missing questions were analyzed for content validity. Cronbach α and item-total correlation coefficients (ITCCs) were calculated for internal consistency. Spearman correlation tests were performed within AOSpine PROST items and in correlation to SF-36. Test-retest reliability was assessed using intraclass correlation coefficients (ICCs). Factor analysis was performed to explore any dimensions within AOSpine PROST. RESULTS. The AOSpine PROST was translated adapted into English using established guidelines. Of 196 enrolled patients, 162 (82.7%) met the inclusion criteria and provided sufficient data. Content validity showed good results, and no floor and ceiling effects were seen. The internal consistency was excellent (Cronbach α = 0.97; ITCC 0.50–0.90) as well as test–retest reliability (ICC = 0.97). Spearman correlations were good (0.29–0.85). The strongest correlations of AOSpine PROST with SF-36 were seen with the physical components (0.69–0.82; P < 0.001). Factor analysis revealed two possible dimensions (Eigen values >1), explaining 75.7% of variance. CONCLUSION. The English version of AOSpine PROST showed very good validity and reliability. It is considered as a valuable tool, and has the potential to contribute to the reduction of ongoing controversies in spine trauma care. Level of Evidence: 2