Micronutrient Supplementation and Chronotherapy in Children With ADHD (SMART-ADHD)

Participants will receive the study nutritional supplementation consisting of a broad-spectrum multivitamin and mineral supplement together with chronotherapy-based guidance on sleep and meal timing.

Participants will receive USANA Usanimals Chewable Tablets for 12 weeks at a dose of 2 tablets daily: 1 tablet after breakfast and 1 tablet after dinner.

Participants in the intervention group will receive chronotherapy-based lifestyle guidance for 12 weeks, focusing on maintaining consistent sleep and wake times, regular meal timing, and alignment of daily routines with circadian rhythms. Parents or caregivers will be provided with guidance to support implementation and adherence throughout the intervention period.

Participants will continue their usual care during the 12-week study period without receiving the study nutritional supplements or chronotherapy intervention.

ADHD symptoms will be assessed using the Conners Parent Rating Scale. The primary outcome will evaluate the change in parent-reported ADHD symptom severity from baseline to Week 12, with particular emphasis on the Inattention domain. Higher scores indicate greater ADHD symptom severity; therefore, a reduction in score from baseline indicates improvement in symptoms.

ADHD symptoms will be assessed using the Swanson, Nolan, and Pelham Rating Scale-IV (SNAP-IV). Changes in parent-reported Inattention and Hyperactivity/Impulsivity symptom scores from baseline to Week 12 will be evaluated. Higher scores indicate greater ADHD symptom severity; therefore, a reduction in score indicates improvement.

Changes in children's sleep habits and sleep-related difficulties will be assessed using the parent-reported Children's Sleep Habits Questionnaire (CSHQ). The questionnaire evaluates sleep-related domains including bedtime resistance, sleep onset delay, sleep duration, sleep anxiety, night wakings, parasomnias, sleep-disordered breathing, and daytime sleepiness. Changes in total CSHQ scores and relevant subscale scores from baseline will be assessed during the intervention period and at the 3-month follow-up. Higher scores indicate greater sleep-related difficulties.

Objective sleep-wake patterns will be assessed using the GENEActiv wrist-worn actigraphy device in both intervention and control groups. Participants will wear the device for 7 consecutive days at each assessment time point. Actigraphy-derived outcomes will include sleep duration, sleep efficiency, sleep onset time, wake time, and sleep timing. Changes from baseline will be evaluated at Week 6 and Week 12 to assess the effects of the combined multivitamin-mineral supplementation and chronotherapy intervention on objective sleep-wake patterns.

Changes in bowel habits will be assessed using a 7-day parent-assisted bowel movement diary. Parents or caregivers will record daily bowel movement frequency, stool form using the Modified Bristol Stool Form Scale for Children (mBSFS-C), and associated gastrointestinal symptoms, including straining and abdominal pain. Outcomes will include average bowel movement frequency, distribution of stool form categories, and frequency of reported gastrointestinal symptoms. Changes from baseline will be evaluated at Week 6, Week 12, and the 3-month follow-up (Week 24).