ABSTRACT
OBJECTIVE: To evaluate the interrater and intrarater reliability of North Star Ambulatory Assessment(NSAA)used in the children with Duchenne muscular dystrophy(DMD)and explore the feasibility of evaluating motor function by videos. METHODS: The assessment data of 40 cases of DMD admitted from July 2017 to November 2017 to Peking University First Hospital were analyzed. Forty DMD boys aged 4.3 to 13.4 years were admitted. They were divided into three groups based on their age. Ten boys were younger than 5 years. Eighteen boys were aged 5 to 9 years. Twelve boys were older than 9 years.Three evaluators,A,B,and C,joined the study. In the interrater reliability study,evaluator A performed the evaluation with NSAA on the boys and video-taped their performance,then evaluators B and C scored the performance in the videos independently to examine interrater reliability. After one month,three evaluators rescored the performance according to the videos again to examine the intrarater reliability. The intra-group reliability was calculated according to the NSAA scores evaluated by the evaluators B and C twice for the same child. The consistency of the video score with the on-site score was calculated according to the NSAA score of the two assessments of the same child by evaluator A. Intraclass correlation coefficient(ICC)was calculated to examine the reliability. RESULTS: In the interrater reliability study,total ICC was 0.990,subgroups ICC was from 0.971 to 0.992. In the intrarater reliability study,total ICC was from 0.987 to 0.988. The video score and the on-site score wereconsistent withICCbeing 0.980. CONCLUSION: NSAA is a reliable and practical method to evaluate the motor development of children with DMD. The consistency between on-site scoring and video scores is high.