Effectiveness of Chinese Herbal Medicine on Improving Sleep and Mental Health in Adults: Study Protocol for A Stepped-Wedge Cluster Randomized Trial

Background: Depression, anxiety, and insomnia significantly impact global health and impose a substantial health burden worldwide. Despite preliminary evidence suggesting the potential of Chinese h erbal m edicine (CHM) in managing these conditions, large-scale evaluations are lacking. This  study  aims to examine the effectiveness of CHM for the treatment of adults experiencing mild-to-moderate symptoms of depression, anxiety, and insomnia. Methods: This study will be a multicenter, assessor-blinded, pragmatic stepped-wedge cluster randomized trial. A total of 18 geographic districts in Hong Kong will be included in the study and the randomization will be carried out at the district level.  The CHM intervention will be sequentially rolled out to the 4-6 districts per step according to a computer-generated random number while the remaining districts will continue to stay unexposed to the intervention over the control period.  The CHM intervention employs a three-level stepped-care model: Level 1 involves herbal tisane treatment for mild symptoms; Level 2 provides a standardized CHM intervention for participants who either initially present with moderate symptoms or those from Level 1 who subsequently develop moderate symptoms; Level 3 consists of personalized CHM combined with psychotherapy for individuals whose symptoms do not downgrade to mild level following Level 2 treatment. Symptom severity classification will be established based on the cut-off points from validated questionnaires, including the Patient Health Questionnaire-9, Generalized Anxiety Disorder-7, and Insomnia Severity Index. Primary outcomes include symptoms of depression, anxiety, and insomnia. Outcome assessments will be conducted at baseline, immediately following the intervention, and after the post-intervention follow-up period. Discussion: This study will provide significant insights into the effectiveness of a stepped-care CHM intervention for alleviating depression, anxiety, and insomnia. The results could guide future decision-making regarding the integration of CHM into mainstream healthcare systems in Hong Kong and other countries or regions with similar sociodemographic and cultural contexts