Maternal Vitamin D Level and Attention-Deficit/Hyperactivity Disorder in Offspring: Getting the Most Out of the Data.

We read with great interest the article Sucksdorff et al. "Maternal Vitamin D Levels and the Risk of Offspring Attention-Deficit/Hyperactivity Disorder."1 We commend the authors for this extraordinary work. Several studies have explored this association lately as well.2 It is logistically challenging to conduct this type of study, as it requires long-term follow-up and patient compliance in a vulnerable population. In this letter, we aim to provide a few suggestions for the statistical methodological aspect, which can better guide the clinician in predicting ADHD among offspring.