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Updated: Apr 24, 2026

Qualitative and Quantitative Validation of Tools with Rating Scales Aimed at Assessing the Quality of University Service-Learning
Published on: August 29, 2025
Validity of the modified RULA for computer workers and reliability of one observation compared to six
Yafa Levanon1, Yehuda Lerman, Amit Gefen
1a Department of Occupational Therapy , School of Health Professions, Tel Aviv University , P.O.B. 39040, Ramat-Aviv, Tel Aviv 69978 , Israel.
Abstract:
Awkward body posture while typing is associated with musculoskeletal disorders (MSDs). Valid rapid assessment of computer workers' body posture is essential for the prevention of MSD among this large population. This study aimed to examine the validity of the modified rapid upper limb assessment (mRULA) which adjusted the rapid upper limb assessment (RULA) for computer workers. Moreover, this study examines whether one observation during a working day is sufficient or more observations are needed. A total of 29 right-handed computer workers were recruited. RULA and mRULA were conducted. The observations were then repeated six times at one-hour intervals. A significant moderate correlation (r = 0.6 and r = 0.7 for mouse and keyboard, respectively) was found between the assessments. No significant differences were found between one observation and six observations per working day. The mRULA was found to be valid for the assessment of computer workers, and one observation was sufficient to assess the work-related risk factor.
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