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The Interrater Reliability of the Greek Expanded and Revised Gross Motor Function Classification System and the
Vasileios C Skoutelis1,2,3, Renata Moutsiou1,2, Maria Spanou2,3
1Department of Physiotherapy, "ATTIKON" University General Hospital, 1 Rimini Str., 12462 Chaidari, Attica, Greece.
Insights
The Greek Gross Motor Function Classification System-Expanded & Revised (GMFCS-E&R) shows high reliability between healthcare professionals and parents for classifying children with cerebral palsy (CP). This supports its use in clinical practice and research.
Area of Science:
- Pediatric Neurology
- Rehabilitation Medicine
- Developmental Pediatrics
Background:
- The Gross Motor Function Classification System-Expanded & Revised (GMFCS-E&R) is a key tool for assessing motor function in children with cerebral palsy (CP).
- While Greek versions exist, their interrater reliability among clinicians and parents, especially for older age groups, needed evaluation.
- This study addresses the need to validate the Greek GMFCS-E&R's reliability across different rater groups and age bands.
Purpose of the Study:
- To evaluate the interrater reliability of the Greek version of the GMFCS-E&R.
- To assess agreement among a pediatric neurologist, a pediatric physiotherapist, and parents in classifying children with CP.
- To examine reliability using descriptors and illustrations for older children and adolescents.
Main Methods:
- A cross-sectional study involving 111 children and adolescents with CP (aged 2-18 years).
- Classification using the Greek GMFCS-E&R brochure or descriptors/illustrations by professionals.
- Parental input gathered via the GMFCS Family Report Questionnaire.
- Statistical analysis using Fleiss' kappa and weighted Cohen's kappa to assess agreement.
Main Results:
- Overall interrater reliability was substantial (κF = 0.77), increasing with age.
- Excellent pairwise agreement was observed between all rater combinations, particularly between the neurologist and physiotherapist (κCw = 0.98).
- Parents tended to assign higher GMFCS levels in cases of disagreement, typically within adjacent categories.
Conclusions:
- The Greek GMFCS-E&R demonstrates high interrater reliability among healthcare professionals and parents.
- The system, including descriptors for older children, is reliable for clinical and research use in Greek-speaking populations.
- Parental input via the GMFCS-FR complements clinical assessments, enhancing the tool's utility.
Abstract:
Background/Objectives: The Gross Motor Function Classification System-Expanded & Revised (GMFCS-E&R) is widely used to describe gross motor performance in children with cerebral palsy (CP). Although Greek-language materials are available, interrater reliability across healthcare professionals and parents has not been examined. This study evaluated the reliability of the Greek GMFCS-E&R among a pediatric neurologist, a pediatric physiotherapist, and parents, with an emphasis on descriptors and illustrations for older children and adolescents. Methods: A cross-sectional study was conducted with 111 children and adolescents with CP aged 2-18 years. Professionals classified each child using the Greek GMFCS-E&R brochure (ages 2-6) or the descriptors and illustrations (ages 6-12 and 12-18). Parents completed the age-appropriate GMFCS Family Report Questionnaire. Agreement among the three raters was assessed using Fleiss' kappa (κF), and pairwise agreement using weighted Cohen's kappa (κCw), overall and by age band. Results: Overall interrater reliability was substantial (κF = 0.77). Agreement by GMFCS level ranged from κF = 0.68 (Level V) to κF = 0.85 (Level I). Reliability increased with age, reaching κF = 0.74-0.85 in adolescents. Pairwise agreement was excellent across all rater pairs, with near-perfect concordance between the pediatric neurologist and physiotherapist (κCw = 0.98). In >60% of disagreements, parents assigned higher levels, typically between adjacent categories. Conclusions: The Greek-language GMFCS-E&R demonstrates high interrater reliability among healthcare professionals and parents, with excellent agreement when using descriptors and illustrations for older children and adolescents. The GMFCS-FR effectively incorporates parental perspectives and complements clinical assessment, supporting the use of the Greek GMFCS-E&R in routine clinical practice and research settings.
