Reliability and Validity of the Trunk Control Measurement Scale Among Children and Adolescents With Cerebral Palsy in Tanzania

Abstract

The aim of this study was to investigate the reliability and validity of the Trunk Control Measurement Scale (TCMS) among children with cerebral palsy (CP) who were living in Tanzania. Two physiotherapy trainees, each blinded to the other’s test findings, independently administered the TCMS to 38 children with CP (16 female; M age = 7.2, SD = 4.8 years) twice over sessions separated by a 30-day interval. We assessed internal consistency and intra/inter-rater reliability using Cronbach’s alpha and the Intraclass Correlation Coefficient (ICC), respectively. We examined measurement error through Standard Error of Measurement (SEM) and Minimal Detectable Change (MDC). We assessed construct validity with Spearman's correlation coefficient between the TCMS and both the Gross Motor Function Classification System (GMFCS) and the Manual Ability Classification System (MACS). We found a frank floor effect. Internal consistency (α = 0.945) and reliability indices were excellent for the total scale (ICC for intra-rater reliability = 0.985, inter- reliability = 0.997) and for each sub-scale score. We found low values of SEM (1.7 points) and MDC (4.8 points). Construct validity was supported by moderate and strong correlations between the TCMS and the GMFCS and MACS in this sample. We conclude that the psychometric properties of the TMCS support its clinical and research use for youth with CP in low-income settings.

Trunk Control Measurement Scale (TCMS): Psychometric Properties of Cross-Cultural Adaptation and Validation of the Spanish Version

“…The TCMS-S has shown excellent internal consistency for the total score and three subscales, supporting the construct validity of the scale. These results (about 0.90) were also noted for the original and Tanzanian versions [ 24 , 27 ]. No data on internal consistency were found in the other versions of the TCMS [ 10 , 25 , 26 , 36 , 37 , 38 ].…”

“…A sample size similar to ours (96 participants) can be found in only two previous studies [ 7 , 25 ] and a wide age range of 6 to 19 years has only been included in two other studies [ 10 , 25 ]. Moreover, most studies only include participants with a diagnosis of spastic CP [ 7 , 23 , 24 , 27 , 36 ]. In our sample, as in the German and Turkish versions, we have also included ataxic forms of CP [ 10 , 25 , 26 ].…”

“…Although the TCMS was originally recommended for children of GMFCS levels I, II, and III [ 24 ], we included children of GMFCS level IV to evaluate the psychometric properties of the TCMS-S in this functional level as recommended by the authors of the original version [ 7 , 17 ] and other studies [ 8 , 10 , 25 , 27 ]. Children with GMFCS IV present difficulties with trunk control and posture, which is reflected by the lower TCMS scores, but this does not mean that it is unnecessary to identify where they need upper limb or other support to perform activities and improve their participation [ 6 , 7 ].…”

“…On the one hand, some research has deepened our understanding of the relationship between trunk control and other dimensions of the International Classification of Function in children with CP. Indeed, the relationships between trunk control in children with CP and the level of motor function [ 25 , 26 , 27 ] and performance in activities such as walking are becoming apparent [ 4 , 5 , 7 , 13 ]. Trunk control has also been related to functions such as abdominal strength and incontinence [ 28 ].…”

“…To minimize this risk and ensure that the assessment tools retain their psychometric properties, guidelines recommend a cross-cultural adaptation process [ 34 , 35 ]. The TCMS has been adapted to German [ 10 , 25 ], Korean [ 36 , 37 ], Turkish [ 23 ], and Tanzanian [ 27 ] languages andcultures with excellent results. Moreover, the use of the TCMS has been extended to other populations such as children with ataxic forms of CP [ 38 ], children with acquired brain injury and spinal cord injury [ 10 ], and even adults with spinal deformity [ 39 , 40 ].…”