Structured Observation of Motor Performance in Infants: Level and quality associated with later motor development.

Aim: The aim of this study was to investigate the level of motor development and the quality of motor performance during the first 10 months in relation to the Bayley Scales of Infant Development-third edition (Bayley-III) motor index at 2.5 years.

Methods: Children born very preterm from a population-based study (n = 113) were assessed with the Structured Observation of Motor Performance in Infants (SOMP-I) at 2, 4, 6 and 10 months corrected age and the Bayley-III motor index at 2.5 years corrected age (n = 98). Logistic regressions were performed to investigate the independent association of each SOMP-I domain to Bayley-III motor index.

Results: There were significant associations between the SOMP-I-scores and Bayley-III motor index per every assessment age. At 4 months, both level and quality were independently associated with a later motor outcome, OR for level was 1.26 (95% CI = 1.08-1.50, P = .002) and for quality, 0.75 (95% CI = 0.63-0.90, P = .002). Quality was independently associated with the Bayley-III motor index at 6 and 10 months: OR 0.080 (95% CI = 0.67-0.95 P = .010) and 0.79 (95% CI = 0.64-0.97, P = .026).

Conclusion: Both SOMP-I domains, level and quality, are markers to identify motor problems early. Quality became more important with age.