Psychometric properties of the Fugl-Meyer Assessment (FMA): a systematic review with meta-analysis

Introduction

Stroke is the second cause of death in the world, and the main cause of disability. Using reliable, valid and responsive instrument to assess the sensory and motor function in patients with stroke is crucial in clinical practice and research. Fugl-Meyer Assessment (FMA) is widespread measurement instrument, and it is composed by five domains for Upper Extremity (FMA-UE) and Lower Extremity (FMA-LE), assessing motor activity, sensory response, balance, joint range of motion, and joint pain, for a total of 155 items. Each item is scored by 3-point Likert scale (i..e, 0=unable to perform, 1=performs partially, 2= performs totally) and the maximum score is 226 points. However,  no systematic review is available that summaries evidence on its psychometric properties. Therefore, the aim of this study is to perform a systematic reviews with meta-analysis to assess the psychometric properties (i.e., reliability, validity, responsiveness) of the FMA.

Methods

A literature search was performed in PubMed, EMBASE and CINAHL between the inception to May 2022 with MeSH terms and free words text, according to the COSMIN recommendation. Studies were included if they assessing the psychometric properties of the FMA in patients with stroke. Screening, eligibility, and data extraction processes were performed by two independent reviewers and disagreements were resolved by a third reviewer. Fixed and random effect models were considered for the meta-analysis, and the statistical heterogeneity between the studies was evaluated by I² statistics.

Results

Out of 3193 articles retrieved, 25 met eligibility criteria for systematic review and 23 were included in the meta-analysis (Figure 1). Detailed results of meta-analysis findings are reported in Figure 2 and Figure 3. For intra-rater reliability, the ICC was >0.90, except for some subscales (e.g., FMA joint pain:  ICC=0.79). Also, for inter-rater reliability, the ICC was >0.90 for all scales except one (i.e., FMA-LE Passive joint motion, ICC= 0.87). We found several high values for measurement error ​​for the subscales with few items (e.g. FMA-LE Sensation 0.12 points); on the other hand we found a reasonable measurement for FMA Total Score. For construct validity from weak to strong correlations were found between FMA subscale and different measurement instruments. Few study assessed the responsiveness of two FMA subscales.

Discussion and Conclusion

FMA subscales proved to be reliable and valid; however, the measurement error was high for some subscales. Evidence on FMA subscales responsiveness are limited. FMA subscales can be used to assess the sensory and motor function in patients with stroke in several measurement between the same assessor or with different assessors. However, our findings suggest to use care when using FMA subscales for capture the change of sensory and motor function after a treatment in patients with stroke. Future studies should fill in this gap.

REFERENCES

Fugl-Meyer AR, et al. The post-stroke hemiplegic patient. 1. a method for evaluation of physical performance. Scand J Rehabil Med. 1975;7(1):13-31.

Terwee CB, et al. Development of a methodological PubMed search filter for finding studies on measurement properties of measurement instruments. Qual Life Res. 2009 Oct;18(8):1115-23.

Terwee CB, et al. Quality criteria were proposed for measurement properties of health status questionnaires. J Clin Epidemiol. 2007;60(1):34-42.