Developmental Coordination Disorder (DCD) is a motor neurodevelopmental disorder characterized by a significant delay in acquiring coordinated motor skills as expected according to the chronological age and learning opportunities. Motor and behavioral problems in children with chronic DCD severely limit their daily activities, academic achievement, and class performance. Children with DCD show great difficulties in social and academic tasks and scholastic achievements. It is found that motor coordination difficulties in 5-8 years old children were associated with impaired reasoning, numerical skills, pattern imitation, fine motor skills, and memory function. Therefore, children with DCD experience more learning-related problems than normal children. One of the psychological aspects that is affected by DCD is perceived competence. This competence is one of the crucial factors in social activities such as participation in games and sports and is one of the most important prerequisites of motivation. This study aimed to compare the effectiveness of school group games on motor skills and perceived competence between normal girls and those with DCD.

The method of the present study was quasi-experimental with a pretest-posttest design and a control group. The study's statistical population consisted of all primary school students in Babol City, Iran, aged 9 to 12 years, and studying in the academic year 2019-2020. Of them, 30 DCD children and 30 normal children were selected and divided into four groups: control-DCD, experimental-DCD, control-normal, and experimental-normal (n=15 for each group). Initial diagnosis of DCD was performed using the Revised Developmental Coordination Disorder Questionnaire (DCDQ-7) (Wilson et al., 2009). The final diagnosis of DCD and motor proficiency was performed using Movement Assessment Battery for Children-Second Edition (MABC-2) (Henderson et al., 2007). To evaluate the perceived competence, we used the Physical Self-Description Questionnaire (Marsh et al., 1994). Both experimental groups underwent the training program 5 days a week for 8 weeks, while the two control groups performed only daily activities. In the end, all four groups participated in the posttest. The obtained data were analyzed using descriptive (mean and standard deviation) and inferential statistics (analysis of variance, analysis of covariance, and LSD post hoc test) in SPSS software version 19. The significance level of all statistical tests was 0.05.

The results showed a significant difference between the four groups in the variables of manual dexterity (p<0.001), receiving and throwing (p<0.001), balance (p<0.001), the total score of motor skills (p<0.001), and perceived competence (p<0.001). Experimental groups performed better than control groups in the posttest of all studied variables (p<0.05). Also, the difference in the scores of the experimental groups of DCD and normal was negative in all variables. However, this difference was significant only in the subscales of receiving and throwing (p=0.023) and balance (p=0.009).

According to the findings, group games improve motor skills and perceived competence in normal and DCD children. However, these games have a more significant impact on DCD children.