Infant Development and Early Aquatic Stimulation

Measure Unit: Composite Score (0-100)

Description: A single feasibility score will be calculated by aggregating multiple indicators: number of sessions attended/missed, dropout rate, impact of inclusion/exclusion criteria on recruitment, rate of adverse events, parental satisfaction, and adherence to protocol activities. Each indicator will be scored and combined into a composite score ranging from 0 (lowest feasibility) to 100 (highest feasibility), reflecting the overall feasibility of the intervention protocol.

Child development will be assessed using the Bayley-III instrument. The assessment begins with age-appropriate tasks and is scored as 1 if the task is completed and 0 if it is not. The assessment ends when the child fails five consecutive tasks. Each domain generates a raw score, which can be converted into balanced and composite scores using tables provided in the manual. The balanced score will classify the child from 1 to 19. The mean is 10 and a standard deviation of ±3 points, being classified as expected (7 to 13 points), below expected (<7 points), and above expected (<13 points). The composite score is based on age norms, classifying the child from 40 to 160. The mean score is 100, with a standard deviation of ±15 points.

For economic classification, the Brazilian Economic Classification Criteria (CCEB) from the Brazilian Association of Research Companies (ABEP) 2018 will be used. This criteria assigns a score based on the assets and education of the head of the household. Based on this score, the family is classified on an ordinal scale from E to A.

The Affordances in the Home Environment for Motor Development (AHEMD) will be used to assess the opportunities children have at home. The instrument has been translated and validated for the Brazilian population and aims to assess the quality and quantity of opportunities for motor stimulation in children's homes. The instrument should be completed based on reports from parents or caregivers. It is divided into two categories, according to the child's age: 2 to 18 months and 18 to 42 months. After completing the questionnaire, the scores for each dimension are calculated by adding the points from the questions and then totaled to obtain the total score. The maximum score for the questionnaire is 20 points, and it can be classified as high (17 to 20 points), medium (10 to 16 points), and low (less than 9 points).

To assess overall development, we used an instrument translated and adapted to the Brazilian version of the "Survey of Well-being of Young Children (SWYC)." This instrument is presented in the form of a compilation of questionnaires, 12 in total, in which each section assesses a domain of the child's well-being, and a score is generated at the end of each domain. Based on this score and the child's age, the administrator can use a table to determine whether the score is the minimum expected for that age. The SWYC can be accessed at: https://www.tuftsmedicine.org/medical-professionals-trainees/academic departments/department-pediatrics/survey-well-being-young-children/age-specific-forms.

Initially, parents and/or guardians will answer a questionnaire prepared by the authors about sociodemographic and biological data characterizing the sample, such as: sex, age, aspects related to the gestational period, family history, and data on the infant's health and habits.