Validating the Rett Syndrome Gross Motor Scale

Article title

Downs J, Stahlhut M, Wong K, Syhler B, Bisgaard A-M, Jacoby P, et al. (2016) Validating the Rett Syndrome Gross Motor Scale. PLoS ONE 11(1):e0147555. doi:10.1371/journal.pone.0147555. Download snapshot, see article abstract.

Background

Challenges to motor abilities and movement are common in Rett syndrome. Our study investigated the quality of measurements obtained using the Rett Syndrome Gross Motor Scale, a measure developed to explore gross motor abilities in females with this condition. 

What we did

We collected video of gross motor skills for 255 girls and women registered with the Australian Rett Syndrome Database. Families showed their daughters' abilities to sit, stand, change position, walk, and more challenging motor skills such as running. Videos were supplemented with a checklist of parent-reported gross motor skills.

What we found

Compared with children younger than eight years and taking into account the effects of mutation type, overall motor scores were reduced in adults. Individuals with the p.Arg133Cys, p.Arg294* or p.Arg306Cys mutation achieved better scores than those with a large deletion. The repeatability of clinical assessment using the Rett Syndrome Gross Motor Scale was excellent.

What does it mean

Our study used a large data set to evaluate the quality of measurement of the Rett Syndrome Gross Motor Scale and we found that it was both reliable and valid. We suggest it could be an appropriate measure of gross motor skills in clinical practice and as an outcome measure in clinical trials.