Feeding development in healthy infants: A comparative framework for children with Spinal Muscular Atrophy – The DySMAnorm study

Objectives: Normative data for swallowing parameters in non-dysphagic, healthy children for instrumental and clinical diagnostics are limited. In children with SMA, where due to the degenerative nature a deterioration in swallowing function in the first months of life is possible despite disease-modifying therapy, regular monitoring is required. The DySMA (Dysphagia in Spinal Muscular Atrophy) is a tool available to assess both physiological feeding development and specific abnormalities in children with SMA. We aimed to generate normative data for the DySMA in a sample of healthy infants to facilitate comparisons with children with SMA. Methods: Healthy infants and toddlers aged zero to 24 months were recruited and divided into seven age groups. Two speech-language pathologists assessed the children according to the DySMA study protocol. The data were evaluated descriptively and the inter-rater reliability was calculated. Results: A total of 92 healthy children were included. The DySMA total score ranged from 21 to 35 and showed excellent inter-rater reliability (ICC = .936; 95 % CI .752 to .984). The maximum score of 35 was first reached from 16 months onwards. Categories representing physiological development showed the most significant age-dependent changes, while no age-related development was observed in categories expressing pathology. Conclusion: The DySMA effectively captures physiological feeding development. A higher total score reflects more comprehensive skills in children, while a lower score indicates a reduced range of abilities. By analyzing the normative sample, this tool makes it possible to represent a deviation from the norm for children with SMA.