IntroductionFatigue is one of the most commonly recorded patient symptoms that can result in deficits in aspects of psychomotor functioning, cognition, work performance and mood. Research shows that bright light and dim light therapy may be an efficacious way to reduce symptoms of fatigue. Still, the feasibility, scalability, individual treatment effects and adverse event heterogeneity of these treatments are unknown.Methods and analysisThe current study evaluates the feasibility, acceptability and effectiveness of a series of personalised (N-of-1) interventions for virtual delivery of bright light therapy and dim light therapy versus usual care treatment for fatigue in 60 participants. We hypothesise that this study will provide valuable information about implementing virtual, N-of-1 randomised controlled trials (RCTs) for fatigue. It will also offer results about determining participants’ ratings of usability and satisfaction with the virtual, personalised intervention delivery system; evaluating participants’ improvement of fatigue symptoms; and, in the long term, identify ways to integrate N-of-1 light therapy trials into patient care.Ethics and disseminationThis trial was approved by the Northwell Health Institutional Review Board. The trial results will be published in a peer-reviewed journal. All publications resulting from this series of personalised trials will follow the Consolidated Standards of Reporting Trials extension for N-of-1 trials CENT 2015 reporting guidelines.Registration detailsThis trial is registered inwww.ClinicalTrials.gov(numberNCT04707846).Trial registration numberNCT04707846.

Background Poor sleep, defined as short-duration or poor-quality sleep, is a frequently reported condition with many deleterious effects including poorer cognitive functioning, increased accidents, and poorer health. Melatonin has been shown to be an efficacious treatment to manage symptoms of poor sleep. However, the treatment effects of melatonin on sleep can vary greatly between participants. Personalized, or N-of-1, trial designs represent a method for identifying the best treatment for individual participants. Although using N-of-1 trials of melatonin to treat poor sleep is possible, the feasibility, acceptability, and effectiveness of N-of-1 trials using melatonin are unknown. Using the National Institutes of Health Stage Model for Behavioral Intervention Development, a stage IB (intervention refinement, modification, and adaptation and pilot testing) design appeared to be needed to address these feasibility questions. Objective This trial series evaluates the feasibility, acceptability, and effectiveness of a series of personalized interventions for remote delivery of melatonin dose (3 and 0.5 mg) versus placebo supplements for self-reported poor sleep among 60 participants. The goal of this study is to provide valuable information about implementing remote N-of-1 randomized controlled trials to improve poor sleep. Methods Participants will complete a 2-week baseline followed by six 2-week alternating intervention periods of 3 mg of melatonin, 0.5 mg of melatonin, and placebo. Participants will be randomly assigned to 2 intervention orders. The feasibility and acceptability of the personalized trial approach will be determined with participants’ ratings of usability and satisfaction with the remote, personalized intervention delivery system. The effectiveness of the intervention will be measured using participants’ self-reported sleep quality and duration and Fitbit tracker–measured sleep duration and efficiency. Additional measures will include ecological momentary assessment measures of fatigue, stress, pain, mood, concentration, and confidence as well as measures of participant adherence to the intervention, use of the Fitbit tracker, and survey data collection. Results As of the submission of this protocol, recruitment for this National Institutes of Health stage IB personalized trial series is approximately 78.3% complete (47/60). We expect recruitment and data collection to be finalized by June 2023. Conclusions Evaluating the feasibility, acceptability, and effectiveness of a series of personalized interventions of melatonin will address the longer term aim of this program of research—is integrating N-of-1 trials useful patient care? The personalized trial series results will be published in a peer-reviewed journal and will follow the CONSORT (Consolidated Standards of Reporting Trials) extension for N-of-1 trials (CENT 2015) reporting guidelines. This trial series was approved by the Northwell Health institutional review board. Trial Registration ClinicalTrials.gov NCT05349188; https://www.clinicaltrials.gov/study/NCT05349188 International Registered Report Identifier (IRRID) DERR1-10.2196/45313

BACKGROUND Poor sleep, defined as short-duration or poor-quality sleep, is a frequently reported condition with many deleterious effects including poorer cognitive functioning, increased accidents, and poorer health. Melatonin has been shown to be an efficacious treatment to manage symptoms of poor sleep. However, the treatment effects of melatonin on sleep can vary greatly between participants. Personalized, or N-of-1, trial designs represent a method for identifying the best treatment for individual participants. Though using N-of-1 trials of melatonin to treat poor sleep is possible, the feasibility, acceptability, and effectiveness of N-of-1 trials using melatonin is unknown. Using the National Institute of Health (NIH) Stage Model for Behavioral Intervention Development, a Stage IB (intervention refinement, modification, and adaptation and pilot testing) design appeared to be needed to address these feasibility questions. OBJECTIVE : The current trial series evaluates the feasibility, acceptability, and effectiveness of a series of personalized interventions for virtual delivery of 3 mg– and 0.5 mg–dose melatonin-versus-placebo supplements for self-reported poor sleep among 60 participants. The goal of this study is to provide valuable information about implementing virtual N-of-1 randomized controlled trials to improve poor sleep. METHODS Participants will complete a 2-week baseline followed by six 2-week alternating intervention periods of 3 mg melatonin, 0.5 mg melatonin, and placebo. Participants will be randomly assigned to 2 intervention orders. Feasibility and acceptability of the personalized trial approach will be determined with participants’ ratings of usability and satisfaction with the virtual, personalized intervention delivery system. Effectiveness of the intervention will be measured using participant self-reported sleep quality/duration and Fitbit tracker–measured sleep duration/efficiency. Additional measures will include ecological momentary assessment (EMA) measures of fatigue, stress, pain, mood, concentration, and confidence as well as measures of participant adherence to the intervention, use of the Fitbit tracker, and survey data collection. RESULTS As of the submission of this protocol, recruitment for this NIH Stage IB personalized trial series is approximately 78.3% complete (n = 47). We expect recruitment and data collection to be finalized by May of 2023. CONCLUSIONS Evaluating feasibility, acceptability, and effectiveness of a series of personalized interventions of melatonin will address the longer-term aim of this program of research—is integrating N-of-1 trials useful patient care? The personalized trial series results will be published in a peer-reviewed journal and will follow the CONSORT extension for N-of-1 trials (CENT 2015) reporting guidelines. This trial series was approved by the Northwell Health Institutional Review Board (IRB). CLINICALTRIAL ClinicalTrials.gov (number NCT05349188).