Cross-cultural adaptation and psychometric evaluation of the Communication Function Classification System-Thai version for individuals with cerebral palsy in Thailand
Main Article Content
Abstract
Background: Cerebral palsy (CP) is a neurodevelopmental disorder that affects motor functions and is often accompanied by impairments such as speech and communication challenges. Functional classification systems are increasingly used to describe daily activities and participation, aiming to guide comprehensive and effective treatment planning that improves patients’ quality of life. The Communication Function Classification System (CFCS) is a tool designed to describe communication functions in the daily lives of individuals with CP. Nonetheless, the absence of a Thai version of the CFCS highlighted the need for this study.
Objectives: This study aimed to translate and culturally adapt the CFCS into Thai (CFCS-TH) and to evaluate its psychometric properties, including validity and reliability, in individuals with CP in Thailand.
Materials and methods: The study was conducted in two phases: (1) cross-cultural adaptation and translation of the CFCS into Thai using a six-step forward and backward translation method, and (2) psychometric evaluation of the CFCS-TH, focusing on content validity, inter-rater reliability, and intra-rater reliability. Validity was assessed using the content validity index (CVI), while reliability was measured using weighted kappa statistics (ƙ). A total of 35 individuals with CP, aged 2-18 years, participated in the study. The raters included one speech-language pathologist (SLP), two physical therapists (PTs), and 35 parents, each of whom rated the level of communication function of the individuals with CP twice.
Results: The cross-cultural adaptation of the CFCS to Thai was carried out by ensuring that the language and terminology were appropriate for Thai users while maintaining the conceptual integrity and purpose of the tool. The CFCS-TH translation steps included vocabulary and syntax selection, equivalency review, and revisions from translators, an expert committee, and pretest users, followed by approval from the instrument developers. The CFCS-TH demonstrated excellent content validity, with an item-level CVI and scale-level CVI of 1.0, indicating that the CFCS-TH could measure its intended construct. Inter-rater reliability was good between the SLP and PTs (ƙ=0.71), good between the SLP and parents (ƙ=0.66), and fair between PTs and parents (ƙ=0.55). When separating the data by the first and second classification rounds, agreement between the SLP and PTs remained good with a slight decrease (ƙ=0.73 and 0.69). The SLP-parent agreement remained consistently good across both rounds (ƙ =0.61 and 0.66), while the PTs-parents agreement improved from fair to good (ƙ=0.48 and 0.62). Intra-rater reliability was excellent for the SLP (ƙ=0.92) and very good for PTs (ƙ = 0.91) and parents (ƙ=0.86).
Conclusion: The CFCS-TH is a valid and reliable tool for describing the communication functions of individuals with CP in Thailand. This tool provides a standardized framework for assessing communication performance to support clinical and research efforts aimed at intervention planning and improving the quality of life for individuals with CP.
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References
Gulati S, Sondhi V. Cerebral palsy: an overview. Indian J Pediatr. 2018; 85: 1006-16. doi: 10.1007/s12098-017-2475-1.
Pennington L. Cerebral palsy and communication. J Paediatr Child Health. 2008; 18: 405-9. doi: 10.1016/j.paed.2008.05.013.
McFadd ED, Hustad KC. Communication modes and functions in children with cerebral palsy. J Speech Lang Hear Res. 2020; 63: 1776-92. doi: 10.1044/2020_jslhr-19-00228.
Stucki G, Grimby G. Applying the ICF in medicine. J Rehabi Med. 2004; 44: 5-6. doi: 10.1080/16501960410023573.
Ogoke CC. Cerebral palsy-clinical and therapeutic aspects [Internet]. London: IntechOpen; 2018 [cited 2021 Jan 20]. Available from:https://www.intechopen.com/books/7072
Palisano R, Rosenbaum P, Walter S, Russell D, Wood E, Galuppi B. Development and reliability of a system to classify gross motor function in children with cerebral palsy. Dev Med Child Neurol. 1997; 39(4): 214-23. doi:10.1111/j.1469-8749.1997. tb07414.x.
Eliasson AC, Krumlinde‑Sundholm L, Rösblad B, Beckung E, Arner M, Öhrvall AM, et al. The Manual Ability Classification System (MACS) for children with cerebral palsy: scale development and evidence of validity and reliability. Dev Med Child Neurol. 2006; 48(7): 549-54. doi:10.1017/S0012162206001162.
Rosenbaum P, Eliasson AC, Hidecker MJC, Palisano RJ. Classification in childhood disability: focusing on function in the 21st century. J Child Neurol. 2014; 29: 1036-45. doi: 10.1177/0883073814533008.
Hidecker MJC, Paneth N, Rosenbaum PL, Kent RD, Lillie J, John B. Eulenberg, et al. Communication Function Classification System (CFCS) [Internet]. Wyoming: Communication function classification systems; 2011. [cited 2021 June 29]. Available from: http://cfcs.us/wp-content/uploads/2014/02/CFCS_universal_2012_06_06.pdf.
Hidecker MJC, Paneth N, Rosenbaum PL, Kent RD, Lillie J, Eulenberg JB, et al. Developing and validating the communication function classification system for individuals with cerebral palsy. Dev Med Child Neurol. 2011; 53: 704-10. doi: 10.1111/j.1469-8749.2011.03996.x.
Zwart KEV, Geytenbeek JJ, de Kleijn M, Oostrom KJ, Gorter JW, Hidecker MJC, et al. Reliability of the Dutch-language version of the communication function classification system and its association with language comprehension and method of communication. Dev Med Child Neurol. 2016; 58: 180-8. doi: 10.1111/dmcn.12839.
Soleymani Z, Joveini G, Baghestani AR. The communication function classification system: cultural adaptation, validity, and reliability of the Farsi version for patients with cerebral palsy. Pediatr Neurol. 2015; 52: 333-7. doi: 10.1016/j.pediatrneurol.2014.10.026.
Yan-na W, Wei S. Reliability and validity of Chinese communication function classification system (Fudan). Chin J Evid Pediatr 2017; 12: 321-7. doi: 10.3969/j.issn.1673-5501.2017.05.001.
Choi JY, Hwang EH, Rha D, Park ES. Reliability and validity of the Korean-language version of the communication function classification system in children with cerebral palsy. Child Care Health. Dev. 2018; 44: 140-6. doi: 10.1111/cch.12507.
Mutlu A, Kaya Kara Ö, Livanelioğlu A, Karahan S, Alkan H, Yardımcı BN, et al. Agreement between parents and clinicians on the communication function levels and relationship of classification systems of children with cerebral palsy. Disabil Health J. 2018;11(2):281-6. doi:10.1016/j.dhjo.2017.11.001.
A lghamdi MS, Chiarello LA, Palisano RJ, McCoy SW. Understanding participation of children with cerebral palsy in family and recreational activities. Res Dev Disabil. 2017; 69: 96-104. doi: 10.1016/j.ridd.2017.07.006.
Küçükakkaş O, Yılmaz Bairamov N, Yurdakul OV, İnce B. Evaluation of factors affecting communication functions in children with cerebral palsy. Turk J Pediatr Dis. 2021; 15: 110-16. doi: 10.12956/tchd.747013.
Ramrit S, Emasithi A, Amatachaya S, Siritaratiwat W. Reliability of GMFCS-E&R and GMFCS-FR Thai version in children with cerebral palsy. J Med Tech Phy Ther. 2014; 26: 67-75 (in Thai). Available from: https://he01.tci-thaijo.org/index.php/ams/article/view/66350.
Manual Ability Classification System. Manual ability classification system for children with cerebral palsy 1-18 years. [Internet]. [cited 2021 June 6]. Available from: https://macs.nu/files/MACS_Thai_2016.pdf.
Beaton DE, Bombardier C, Guillemin F, Ferraz MB. Guidelines for the process of cross-cultural adaptation of self-report measures. Spine J 2000; 25: 3186-91. doi: 10.1016/j.spinee.2000.09.013.
Phatthanasombatsuk M. Validation of nursing and social science research instruments. The Southern College Network Journal of Nursing and Public Health 2021; 8: 329-43 (in Thai). Available from: https://he01.tci-thaijo.org/index.php/scnet/article/view/240643/169173
Polit DF, Beck CT, Owen SVJRin, health. Is the CVI an acceptable indicator of content validity? Appraisal and recommendations. Res Nurs Health 2007; 30: 459-67. doi: 10.1002/nur.20199.
Bujang MA, Baharum N. Guidelines of the minimum sample size requirements for Kappa agreement test. Epidemiol Biostat Public Health. 2017; 14: e122671-7. doi: 10.2427/122671.
Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics. 1977; 33(1): 159-74. doi:10.2307/2529310.
Chaihanawirote U, Vantum C. Evaluation of content validity for research instrument. Journal of Nursing and Health Sciences. 2017; 11: 105-11 (inThai).
Ezeizabarrena MJ, Kovacevic M. Editorial: Parental questionnaires as a reliable instrument for the assessment of child language development. Front Psychol. 2024; 15: 1471747. doi: 10.3389/fpsyg.2024.1471747.
Virella D, Pennington L, Andersen GL, Andrada MG, Greitane A, Himmelmann K, et al. Classification systems of communication for use in epidemiological surveillance of children with cerebral palsy. Dev Med Child Neurol. 2016; 58(3): 213-316. doi: 10.1111/dmcn.12802.
Cunningham BJ, Rosenbaum P, Hidecker MJC. Promoting consistent use of the communication function classification system (CFCS). Disabil . 2016; 38: 195-204. doi: 10.3109/09638288.2015.1027009.