Cross-sectional developmental trajectories in the adaptive functioning of children and adolescents with Down syndrome.
In Down syndrome, standard scores slip even while raw skills slowly climb—plan goals by mental age, not birthday.
01Research in Context
What this study did
Onnivello et al. (2024) mapped how daily living and communication skills grow in kids and teens with Down syndrome.
They used cross-sectional data. That means they looked at many age groups at one point in time.
Standard scores and age-equivalent scores were both tracked.
What they found
Standard scores went down as kids got older.
Age-equivalent scores still went up.
Mental age predicted communication better than calendar age.
How this fits with other research
Edgin et al. (2005) saw the same pattern in kids with severe ID. Standard scores dropped while real skills inched up.
English et al. (1995) tracked adults with Down syndrome. Receptive language kept falling while expressive language stayed flat.
The 2024 child data line up with the adult trend. Drop in standard scores starts early and continues.
Redquest et al. (2021) found speech production accuracy did not improve over 21 months. Together these studies show limited natural growth in communication skills.
Why it matters
Stop waiting for big jumps in standard scores. They rarely happen.
Track age-equivalent scores instead to spot real but small gains.
Use mental-age goals in communication programs. Calendar age sets the bar too high.
Check hearing, vision, and parent stress. These can drag skills down further.
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02At a glance
03Original abstract
BACKGROUND: Persons with Down syndrome (DS) reveal adaptive functioning (AF) difficulties. Studies on AF in DS have focused mainly on describing the profile (i.e., strengths in socialization, and weaknesses in communication), while less is known about age-related differences. This study aimed to elucidate how AF changes with age in children and adolescents with DS, taking a cross-sectional developmental trajectory approach. Moreover, the contribution of both chronological age (CA) and mental age (MA) on AF development was explored. METHOD: This study involved 115 children and adolescents (between 3 and 16 years old) with DS. Parents were interviewed about their children's AF on communication, daily living and socialization skills. Children and adolescents with DS were assessed on their developmental level. RESULTS: While participants' standard scores on AF decreased linearly over time, their age-equivalent scores increased with linear or segmented patterns, depending on the skill considered. CA and MA were related to daily living skills and socialization to much the same degree, while MA correlated more strongly than CA with communication. CONCLUSION: This study contributes to the understanding of how AF develops in children and adolescents with DS, showing that CA and MA both contribute to shaping the skills involved.
Research in developmental disabilities, 2024 · doi:10.1016/j.ridd.2023.104641