Randomized Behavioral Sleep Clinical Trial to Improve Outcomes in Children With Down Syndrome.

The study had 80% power to detect an effect size (f-squared) of about 0.60, which is many times larger than the effects actually observed and twice the conventional large-effect threshold, so it was underpowered to detect the modest differences that might exist. No waitlist control group was included, making it harder to separate true treatment effects from regression to the mean. Inclusion required sleep problems at least one night per week but set no minimum score on any specific measure, so some participants may not have had high enough baseline scores to show meaningful change. Five sessions may not have given families enough time to implement the behavioral strategies. At follow-up, mean scores on parent-reported sleep problems were still above clinical cut-offs, so at least some participants may not have had clinically meaningful improvement. The same therapist delivered both groups' sessions, and the attention and therapeutic relationship were identical, so any benefit from the therapist's presence cannot be separated from the specific strategies.

Funded by the NIH (extramural). No other conflicts of interest are stated in the provided text.

Do not read the improvement in both groups as evidence that the behavioral sleep strategies are effective. The primary comparison found no difference between groups, the study was underpowered to detect the small effects that were observed, and both groups received a session on basic sleep management, which may account for the gains seen in both.