Construct and criterion validity of the Malaysia version of Lower Extremity Functional Scale (LEFS)

Objective The objective of this study is to translate the Lower Extremity Functional Scale (LEFS) into the Malay language and to validate the resulting version. Methods A two-stage observational study was conducted. The LEFS was initially cross-culturally adapted to Malay language through double forward and backward translation. The finalized version of Malay LEFS (M-LEFS) was subsequently validated for both construct validity and criterion validity. Participants (n = 208) with normal lower limb condition and various lower limb conditions completed the M-LEFS. Results Reliability of M-LEFS revealed excellent Cronbach's alpha value of 0.98. Construct validity, evaluated using exploratory factor analysis, exhibited good factor loadings (>0.6) of all 20 items. Interestingly, we extracted 2 components which was not reported elsewhere. With a cut-off point of 60, the sensitivity of the scale was 99% and the specificity was 81%. Conclusions The M-LEFS had very good psychometric properties among the studied population. Further studies are needed to enhance these preliminary outcomes in Malaysia.