Background & Objective: Applicability and adaptability of the current movement assessment norms on Iranian population should survey because there is variety in cultural and geographical characteristics in comparison with western countries. The movement assessment battery for children second edition (MABC2) (Henderson, 2007) is one of the most tools that used it to assessment for diagnostic developmental coordination disorder (DCD) in children. In recent years, the interest of Iranian researchers and clinicians to use of MABC2 have increased, though the validity of its norms has not been explored. This study aimed to compare the motor performance of 7–10 years old children from Arak city as a representative of the Iranian population with MABC2 norms from Britannia.
Methods: Five hundred and three typically developed children (244 girls and 259 boys) 7–10 years old using stratified sampling from Arak (Markazi province, Center of Iran) city`s schools participated in this study. All children were tested individually with movement assessment battery for children–2. Data were compared with 2007 standardization sample, age band–2. Data were analyzed at the item, sub–scales, and total test score levels. MABC2 manuals provide a traffic light system based on 5 and 15 percentile rank which categorize children in three–zone; impaired, at–risk and typically developed. Validity and reliability of MABC2 have been investigated in several studies; for example, Kita et al. (2016) found high factorial validity and acceptable internal consistency (0.602). Also, holm et al. (2013) reported Intra and inter–rater reliability 0.68 and 0.62, respectively. The one–way ANOVA, one–sample t–test and one–way MANOVA were used to data analysis. Significant level was set at 0.05, and all data were analyzed using SPSS 21 for Windows (SPSS, Chicago, IL, USA).
Results: In all ages, Iranian children performed more poorly on balance than the Britain norms (p<0.001) while, their manual dexterity skills were superior to the Britain norm (p=0.004). No statistically significant findings were observed in aiming and catching (p=0.83). In younger children (7 and eight years old) differences in the total test, the score was in favor of Britain (p<0.001). When age increased, Iranian children enhanced their performances, so that in 9 and ten years old children significant differences in total test score disappeared, though it was still lower (p=0.049), (p=0.304). The largest effect size observed in balance subscale and items. Using the Britain norm, the prevalence of DCD showed 9.5%, which indicate an increased possibility of false positive. Also, totally about 30% of Iranian children fell below 15–percentile rank, which shows two times more than the Britain peers do. The one–way ANOVA revealed a significant effect for gender, though the effect size did not rise 0.059 and assumed not to be sufficiently large to be clinically significant. Of the present study sample, 13.9% of boys scored percentile 5 and below while only 4.9% of girls were in this zone.
Conclusion: According to significant differences in motor performance between two populations, consistent with some previous studies, necessity of adjustment to some items and using specific–culture norms was highlighted. Present study could be considered as a step toward standardization of MABC2 in Iran.