Abstract
BACKGROUND: Activities of daily living at home (ADL) are a fundamental aspect of adaptive behavior in children, youth, and adults with Down syndrome (DS). However, they have received limited attention in relation to this topic. This highlights the lack of a validated instrument for the DS population in Chile. OBJECTIVE: a) Verify validity and reliability of the Scale for Assessing of Daily Living at Home (SAADL) and b) Develop benchmarks for daily activities in children, young people, and adults with DS in central-southern Chile. METHODS: A descriptive cross-sectional study was conducted in children, youth and adults with DS in Chile. A total of 320 young people (168 males and 152 females) with an age range of 6 to 29 years were recruited. Weight and height were assessed and body mass index BMI was calculated. The SAADL was used to measure activities of daily living at home. Reliability was determined by stability measures (test and retest) and validity by confirmatory factor analysis (CFA). Percentiles were constructed using the LMS technique (L(t) Box-Cox power, M(t) median and S(t) coefficient of variation). RESULTS: In both sexes, the technical error of measurement (TEM) showed very low values, with an absolute error of less than 0.23 and a relative error of 0.85%. The values of the concordance correlation coefficient showed high values of precision and accuracy from 0.94 to 0.98. The Kappa analysis showed substantial agreement values from 0.73 to 0.78. Mean differences in the Bland-Altman plot were minimal (~0.32 to ~0.56 points). The CFA demonstrated the validity of the scale (RMSEA: 0.057). Percentiles were plotted for SAADL (p5, p10, p15, p25, p50, p75, p85, p90 and p95). CONCLUSION: The study confirms that the SAADL is highly valid and reliable for assessing activities of daily living in children, youth and adults with DS in the south-central region of Chile. Its use is recommended as an effective tool for clinical assessment, early intervention and personalization of care, based on the proposed reference values.