Measurement properties of the 15-item Arabic lower extremity functional scale

Abstract

Purpose

To examine the measurement properties of the 15-item Arabic Lower Extremity Functional Scale (LEFS-Ar) in patients with lower extremity musculoskeletal disorders

Materials and Methods

Patients with lower extremity musculoskeletal disorders (N = 116) completed the 15-item LEFS-Ar, Global Assessment of Function, RAND 36-item Health Survey, and Numeric Pain Rating Scale. A subset of participants completed a retest session within 2 to 7 days that also involved completion of the Global Rating of Change Scale. Internal consistency, test–retest reliability, measurement error, floor and ceiling effects of 15-item LEFS-Ar were examined. Construct validity was also tested by examining a number of predefined hypotheses regarding expected correlation between the 15-item LEFS-Ar and the other measures.

Results

The 15-item Arabic LEFS had excellent internal consistency (Cronbach’s alpha= 0.93) and excellent test–retest reliability (ICC _agreement = 0.95) with no floor or ceiling issues. The standard error of measurement of the Arabic 15-item Arabic LEFS was 2.71 points while the minimal detectable change was 7.51 points. Eighty-three percent of the predefined construct validity correlational hypotheses were supported by the results of the study justifying the construct validity of the 15-item LEFS-Ar.

Conclusion

The 15-item LEFS-Ar demonstrated evidence supporting its internal consistency, test–retest reliability and construct validity as a measure of lower extremity function in Arabic-speaking patients with lower extremity musculoskeletal disorders.

Implications for Rehabilitation

• The 15-item LEFS-Ar demonstrated evidence supporting its internal consistency, test–retest reliability and construct validity as a measure of lower extremity function in patients with lower extremity musculoskeletal disorders.

• The 15-item LEFS-Ar can be used to measure lower extremity function in Arabic-speaking patients with lower extremity musculoskeletal disorders.

Keywords:

• Psychometrics
• measurement properties
• validation
• lower limb
• outcome measure

Acknowledgements

The author extends his appreciation to the College of Applied Medical Sciences Research Center and the Deanship of Scientific Research at King Saud University for funding this research.

Disclosure statement

No potential conflict of interest was reported by the author(s).