Anxiety in Williams Syndrome: The Role of Social Behaviour, Executive Functions and Change Over Time.

The sample was small, with 26 individuals in the cross-sectional group and 17 in the follow-up group, so the study had limited power to detect real differences. The authors did not correct for multiple comparisons because of the small sample, so some reported trends may not hold up. All outcomes came from parent or caregiver report, which can introduce subjective bias and shared variance across the questionnaires. The anxiety measure was designed for children without neurodevelopmental disorders, and an adult version was adapted by changing item wording rather than using a fully validated adult tool. Five individuals were diagnosed from facial features and heart problems rather than genetic testing, which may affect how typical the sample is. The follow-up group was a subset of the cross-sectional group and had partly been reported before, so the samples overlap. The study was observational, so it cannot show that executive or social difficulties caused anxiety, or that anxiety caused them. Parents of more anxious children may have been more likely to take part, although the authors noted wide variation in scores.

Do not conclude that anxiety reliably worsens over four years in Williams syndrome. The average increase was not statistically significant, and the study had low power; it only showed a trend.