The interrater reliability of a functional capacity evaluation: the physical work performance evaluation

Area of Science:

• Occupational Health
• Rehabilitation Medicine
• Ergonomics

Background:

• Functional Capacity Evaluations (FCEs) are crucial for assessing work capacity in individuals with disabilities.
• The Physical Work Performance Evaluation (PWPE) is commonly used for workers experiencing back pain.
• Ensuring reliability in FCEs is vital for consistent and accurate patient assessments.

Purpose of the Study:

• To assess the interrater reliability of specific tasks within the Physical Work Performance Evaluation (PWPE).
• To evaluate the reliability of the Dynamic Strength, Position Tolerance, and Mobility sections of the PWPE.
• To identify potential areas for improvement in the PWPE criteria for functional capacity evaluations.

Main Methods:

• A convenience sample of 40 workers with back pain was recruited from an occupational rehabilitation center.
• Two trained raters evaluated each participant, with one administering the PWPE and the other acting as a silent observer.
• Interrater reliability was calculated using the kappa statistic for 21 tasks and three sections of the PWPE.

Main Results:

• Most PWPE tasks and sections demonstrated substantial to almost perfect interrater reliability (kappa > 0.61).
• Lower reliability was observed for three specific Mobility tasks: ladder climbing (kappa = 0.47), repetitive trunk rotation--standing (kappa = 0.54), and repetitive trunk rotation--sitting (kappa = 0.37).
• The Mobility section itself also showed lower reliability (kappa = 0.54).

Conclusions:

• The PWPE generally exhibits good interrater reliability for assessing functional capacity in back-pain disabled workers.
• Specific mobility tasks, particularly those involving rotation or complex movements, require refined criteria for objective assessment.
• Improving the criteria for identifying physical signs of maximal functional capacity is recommended to enhance PWPE reliability.