Cross-country validity of the Alberta Infant Motor Scale using a Brazilian sample

Abstract

BackgroundPrevious validity studies of the Alberta Infant Motor Scale (AIMS), using raw scores and percentile curves for group comparisons, showed that infants in Brazil achieved gross motor milestones at later ages. Validity of the AIMS norms were later reassessed using a logistic regression model that placed the AIMS items on an age scale. ObjectivesOur study examined the validity of the AIMS norms for Brazilian infants using the recommended method for calculating and comparing item locations. MethodsData from 732 Brazilian infants (2009–11), 3 days to 18 months old, were compared to the AIMS normative sample (n=2202). Logistic regression placed the AIMS items of both samples on age scales representing the age at which 50% of infants passed an item and compared the two datasets. Pearson correlation coefficient tested the association across samples. Results47 of the 58 AIMS items met the criterion for stable regression to calculate item locations of the Brazilian dataset. Based on the age when 50% of the infants passed a criterion, most of the items from the Brazilian sample (n=28) differed by two weeks or less compared to the Canadian normative sample. ConclusionThe sequence and age for the emergence of AIMS items were similar between the Brazilian and Canadian samples. Canadian norms are appropriate for clinical decisions and research with Brazilian infants.