Misclassification due to age grouping in measures of child development

Abstract

The use of age groups produces a large number of misclassifications. Although affected children will usually be close to the threshold, this may lead to misreferrals. Results may help to explain the poor measured agreement of development screens. Scoring methods that treat child age as continuous would improve instrument accuracy.

Correcting for prematurity affects developmental test scores in infants born late and moderately preterm

“…Indeed, the use of agebanded normative scores on Bayley-III test results has recently been shown to affect rates of delay and may result in misclassifications of developmental abilities depending on the child's age relative to agebanded cut-offs. [29] Contrary to expectations, we also found that the application of corrected age did not always result in a higher cognitive or language score, and in many cases lower scores were obtained (cognitive: n=16 (7.2%); language: n=1 (0.5%)). This is a result of the structure of the test in which a drop in scores using corrected age may arise when a different (lower) start point is used.…”

Concurrent Validity of the Ages and Stages Questionnaires and Bayley Developmental Scales in a General Population Sample

“…At the same time, the distribution-based approach should have reduced misclassifications due to problematic norms, as well as misclassifications due to the use of age bands generally. 29 These factors may have balanced the reduction in agreement resulting from the addition of milder cases.…”

“…The use of age groups in measures like the ASQ and BSID-III can also, as the example of the 2-month ASQ illustrates, give rise to systematic misclassifications, with likely overdiagnosis among the younger children within an age band and underdiagnosis among older ones. 29 There are also certain differences between the ASxQ and BSID-III in terms of the domains assessed. Most notably, the ASQ includes personal-social functioning, while the (core) BSID-III does not.…”

Validation and adaptation of rapid neurodevelopmental assessment instrument for infants in Guatemala

“…Child development falls on a spectrum and using wide age bands means that some children will be misclassified as having, or not having, NDIs. This can lower sensitivity of tests to 70% or less (Veldhuizen et al 2014), which may explain the sensitivity levels in our study.…”

“…Child development falls on a spectrum, and using wide age bands means that some children will be misclassified as having, or not having, NDIs. This can lower sensitivity of tests to 70% or less (Veldhuizen et al 2014), which may explain the sensitivity levels in our study. For the RNDA scores, we determined NDI norms based on this Guatemalan sample, converting raw scores for each domain and age group into z-scores and then standardizing scores to a mean of 100 and an SD of 15.…”