Cross Cultural Adaptation Validity and Reliability Test of the Arabic Version of the Outpatient Physical Therapy Improvement in Movement Assessment Log

Background: The Outpatient Physical Therapy Improve-ment in Movement Assessment Log (OPTIMAL) is a self-re-ported instrument designed to assess difficulty and confidence in performing functional movements among physical therapy outpatients. While the OPTIMAL has been translated into sev-eral languages, no validated Arabic version exists. Aim of Study: This study aimed to translate, culturally adapt, and evaluate the psychometric properties of the Arabic version of the OPTIMAL (OPTIMAL-AR) for use among Ar-abic-speaking physical therapy outpatients. Material and Methods: The study involved three expert panels (10 experts each) and 880 adult outpatients (mean age: 35.21±9.00 years) from various physiotherapy clinics. The OPTIMAL-Ar underwent translation, cultural adaptation, and rigorous psychometric testing, including face validity, content validity, construct validity, internal consistency reliability, and test-retest reliability. Internal consistency was assessed using Cronbach’s alpha, while test-retest reliability was evaluated using intra-class correlation coefficients (ICC). Construct va-lidity was examined through factor analysis and correlations with the Activities-specific Balance Confidence (ABC) Scale. Results: The OPTIMAL-Ar demonstrated excellent in-ternal consistency, with Cronbach’s alpha values of 0.950 for the total score, 0.908 for the difficulty domain, and 0.909 for the confidence domain. Test-retest reliability was high, with ICC values of 0.999 for the total score and individual domains (p<0.001). Factor analysis revealed an eight-factor structure, explaining 80.81% of the total variance. Strong negative cor-relations were observed between the OPTIMAL-Ar and the ABC Scale at baseline (r=–0.915, p=0.001) and one week later (r=–0.914, p=0.001), confirming construct validity. The OPTIMAL-Ar was feasible, with an average completion time of 17.41±3.69 minutes and minimal missing data (0.04±0.20 items). Conclusion: The Arabic version of the OPTIMAL is a re-liable, valid, and feasible instrument for assessing functional movement difficulty and confidence among Arabic-speaking physical therapy outpatients. Its strong psychometric proper-ties make it a valuable tool for clinical and research settings