N of 1 randomized trials: a commentary

Protocol for randomized personalized trial for stress management compared to standard of care

Stress is a significant public health burden in the United States, with most Americans reporting unhealthy levels of stress. Stress management techniques include various evidence-based treatments shown to be effective but with heterogeneous treatment responses, indicating a lack of uniform benefits for all individuals. Designed to assess a participant's response to a specific intervention, personalized (N-of-1) trials provide guidance for which treatment (s) work (s) best for the individual. Prior studies examining the effects of mindfulness meditation, yoga, and walking for stress reduction found all three interventions to be associated with significant reductions in self-reported measures of stress. Delivering these treatments using a personalized trial approach has the potential to assist clinicians in identifying the best stress management techniques for individuals with persistently high stress while fostering treatment decisions that consider their personal condition/barriers. This trial will evaluate a personalized approach compared to standard of care for three interventions (guided mindfulness meditation; guided yoga; and guided brisk walking) to manage perceived stress. Participants will respond to daily surveys and wear a Fitbit device for 18 weeks. After a 2-week baseline period, participants in the personalized trial groups will receive 12 weeks of interventions in randomized order, while participants in the standard-of-care group will have access to all interventions for self-directed stress management. After intervention, all participants will undergo 2 weeks of observation, followed by two additional weeks of the stress management intervention of their choosing while continuing outcome measurement. At study completion, all participants will be sent a satisfaction survey. The primary analysis will compare perceived stress levels between the personalized and standard of care arms. The results of this trial will provide further support for the use of personalized designs for managing stress. Clinical Trial Registration: clinicaltrials.gov, NCT05408832. Protocol version: 9/14/2022, 21-0968-MRB.

A Series of Remote Melatonin Supplement Interventions for Poor Sleep: Protocol for a Feasibility Pilot Study for a Series of Personalized (N-of-1) Trials

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.

Series of virtual light therapy interventions for fatigue: a feasibility pilot study protocol for a series of personalised (N-of-1) trials

INTRODUCTION

Fatigue 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 ANALYSIS

The 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 DISSEMINATION

This 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 DETAILS

This trial is registered in www.

CLINICALTRIALS

gov (number NCT04707846).

TRIAL REGISTRATION NUMBER

NCT04707846.

Effectiveness of modified Buzhong Yiqi decoction in treating myasthenia gravis: study protocol for a series of N-of-1 trials

Background

Myasthenia gravis (MG) is an acquired autoimmune disease with high heterogeneity. The disease is chronic, relapsing repeatedly and progressive with acute exacerbation occasionally. Although the treatment of MG has developed, it is still unsatisfactory and has some unexpected side effects. Traditional Chinese medicine (TCM) has shown great potential in MG treatment, including relief of muscle weakness syndrome, improvement of patient’s quality of life, and reduction of side effects of western medicine. The purpose of this study is to evaluate the effectiveness of modified Buzhong Yiqi decoction (MBYD) as an add-on therapy for MG through a small series of N-of-1 trials.

Methods

Single-centre, randomized, double-blind, 3 crossover N-of-1 trials will be conducted to enroll patients with MG diagnosed as spleen-stomach deficiency syndrome or spleen-kidney deficiency syndrome in TCM. Each N-of-1 trial has 3 cycles of two 4-week periods containing the MBYD period and placebo period. The wash-out interval of 1 week is prior to switching each period. Primary outcome: quantitative myasthenia gravis (QMG). Secondary outcomes: the following scales: myasthenia gravis composite (MGC), myasthenia gravis activities of daily living profile (MG-ADL), myasthenia gravis quality of life (MG-QOL); the level of CD4+FoxP3+Treg cells and cytokines (IL-4, IL-17A, INF-γ, TGF-β) in the peripheral blood; the alterations of the composition of gut microbiota; reduction of the side effects of western medicine.

Discussion

Used by WinBUGS software, we will conduct a hierarchical Bayesian statistical method to analyze the efficacy of MBYD in treating MG in individuals and populations. Some confounding variables such as TCM syndrome type and potential carryover effect of TCM will be introduced into the hierarchical Bayesian statistical method to improve the sensitivity and applicability of the trials, and the use of prior available information within the analysis may improve the sensitivity of the results of a series of N-of-1 trials, from both the individual and population level to study the efficacy of TCM syndrome differentiation. We assumed that this study would reveal that MBYD is effective for MG and provide robust evidence of the efficacy of TCM to treat MG.

Trial registration

Chinese Clinical Trial Register, ID: ChiCTR2000040477, registration on 29 November 2020.

Is the N-of-1 method applicable in bodywork research? Lessons learned using a trial as a methodological pilot

N-of-1 trial designs have rarely been used in bodywork research. Using a recent trial as a methodological pilot, critical issues related to the applicability of N-of-1 trials to bodywork are discussed. These include the issues of carry-over effects, bias-controlling approaches and statistical analysis. The discussion highlights the importance of mixed methods and draws some suggestions for a future research program. N-of-1 trials could be used to provide insights about some essential elements of bodywork modalities and their effectiveness.

Protocol for a single patient therapy plan: A randomised, double-blind, placebo-controlled N-of-1 trial to assess the efficacy of cannabidiol in patients with intractable epilepsy

AIM

This paper describes the use of the single patient therapy plan (SPTP). The SPTP has been designed to assess the efficacy at an individual level of a commercially available cannabinoid product, cannabidiol, in reducing seizure frequency in paediatric patients with intractable epilepsy.

METHODS

The SPTP is a randomised, double-blind, placebo-controlled N-of-1 trial designed to assess the efficacy of treatment in a neurology outpatient setting. The primary objective of the SPTP is to assess the efficacy of cannabidiol in reducing seizure frequency in each patient with intractable epilepsy, with change in seizure frequency being the primary outcome of interest. The analysis adopts a Bayesian approach, which provides results in the form of posterior probabilities that various levels of benefit (based on the primary outcome measure, seizure frequency) have been achieved under active treatment compared to placebo, accompanied by decision rules that provide thresholds for deciding whether treatment has been successful in the individual patient. The SPTP arrangement is most accurately considered part of clinical practice rather than research, since it is aimed at making clinical treatment decisions for individual patients and is not testing a hypothesis or collecting aggregate data. Therefore, Human Research Ethics Committee approval was considered not to be required, although it is recommended that hospital Clinical Ethics Committees provide ethical oversight.

CONCLUSION

These SPTP resources are made available so that they may inform clinical practice in the treatment of severe epilepsy or adapted for use in other conditions.

Personal preferences for Personalised Trials among patients with chronic diseases: an empirical Bayesian analysis of a conjoint survey

OBJECTIVE

To describe individual patient preferences for Personalised Trials and to identify factors and conditions associated with patient preferences.

DESIGN

Each participant was presented with 18 conjoint questions via an online survey. Each question provided two choices of Personalised Trials that were defined by up to eight attributes, including treatment types, clinician involvement, study logistics and trial burden on a patient.

SETTING

Online survey of adults with at least two common chronic conditions in the USA.

PARTICIPANTS

A nationally representative sample of 501 individuals were recruited from the Chronic Illness Panel by Harris Poll Online. Participants were recruited from several sources, including emails, social media and telephone recruitment of the target population.

MAIN OUTCOME MEASURES

The choice of Personalised Trial design that the participant preferred with each conjoint question.

RESULTS

There was large variability in participants' preferences for the design of Personalised Trials. On average, they preferred certain attributes, such as a short time commitment and no cost. Notably, a population-level analysis correctly predicted 62% of the conjoint responses. An empirical Bayesian analysis of the conjoint data, which supported the estimation of individual-level preferences, improved the accuracy to 86%. Based on estimates of individual-level preferences, patients with chronic pain preferred a long study duration (p≤0.001). Asthma patients were less averse to participation burden in terms of data-collection frequency than patients with other conditions (p=0.002). Patients with hypertension were more cost-sensitive (p<0.001).

CONCLUSION

These analyses provide a framework for elucidating individual-level preferences when implementing novel patient-centred interventions. The data showed that patient preference in Personalised Trials is highly variable, suggesting that individual differences must be accounted for when marketing Personalised Trials. These results have implications for advancing precise interventions in Personalised Trials by indicating when rigorous scientific principles, such as frequent monitoring, is feasible in a substantial subset of patients.

CONSORT extension for reporting N-of-1 trials for traditional Chinese medicine (CENT for TCM) : Recommendations, explanation and elaboration

BACKGROUND

N-of-1 trial is a desired and appropriate approach to assessing the efficacy and safety of traditional Chinese medicine (TCM) interventions. There have been an increasing number of N-of-1 trials for TCM published. However, a lack of preferred reporting guidance led in the general poor reporting quality of these trials. Due to the unique characteristics of TCM, the working group developed this CONSORT Extension for reporting N-of-1 Trials for Traditional Chinese Medicine (CENT for TCM) to assist TCM researchers in reporting N-of-1 trials for TCM.

METHODS

We registered CENT for TCM at the EQUATOR (Enhancing the QUAlity and Transparency Of health Research) Network (available at equator-network.org). The development was a comprehensive process through collection of the initial reporting items, two-round scientific Delphi consensus survey with 17 panelists, revision and formation of the final reporting checklist.

RESULTS

The checklist includes 25 items within six domains, eight items in which were extended and elaborated on the items of the CENT 2015 checklist. Explanation of the items were listed adequately considering the nature of TCM, introducing the concept of TCM syndrome differentiation and TCM interventions.

CONCLUSIONS

CENT for TCM can be used to assess the completeness of the reporting of N-of-1 trials for TCM. The working group expect that CENT for TCM could be a practical tool to enhance the comprehensiveness and transparency of the design, implementation and reporting of N-of-1 trials for TCM.

Evidence for personalised medicine: mechanisms, correlation, and new kinds of black box

Personalised medicine (PM) has been discussed as a medical paradigm shift that will improve health while reducing inefficiency and waste. At the same time, it raises new practical, regulatory, and ethical challenges. In this paper, we examine PM strategies epistemologically in order to develop capacities to address these challenges, focusing on a recently proposed strategy for developing patient-specific models from induced pluripotent stem cells (iPSCs) so as to make individualised treatment predictions. We compare this strategy to two main PM strategies-stratified medicine and computational models. Drawing on epistemological work in the philosophy of medicine, we explain why these two methods, while powerful, are neither truly personalised nor, epistemologically speaking, novel strategies. Both are forms of correlational black box. We then argue that the iPSC models would count as a new kind of black box. They would not rely entirely on mechanistic knowledge, and they would utilise correlational evidence in a different way from other strategies-a way that would enable personalised predictions. In arguing that the iPSC models would present a novel method of gaining evidence for clinical practice, we provide an epistemic analysis that can help to inform the practical, regulatory, and ethical challenges of developing an iPSC system.

Advancing personalized treatment of Alzheimer's disease: a call for the N-of-1 trial design

There has not been a new treatment for Alzheimer's disease (AD) for over a decade, with a large number of Phase II/III randomized clinical trials failing. Randomized clinical trials examine group effects that may be difficult to extrapolate to the individual patient given the multifactorial pathogenic processes associated with AD, and are increasingly long in duration, expensive to run, requiring large sample sizes that are difficult to recruit. An alternative approach is to consider N-of-1 trial designs. The N-of-1 trial is ideal to evaluate effectiveness of interventions for chronic conditions combining the rigor of a randomized trial with the tailoring of therapy to an individual. This review examines the N-of-1 design, its benefits and limitations, and how it could be implemented to investigate new therapies for AD.

Patient preferences for personalized (N-of-1) trials: a conjoint analysis

OBJECTIVE

Despite their promise for increasing treatment precision, Personalized Trials (i.e., N-of-1 trials) have not been widely adopted. We aimed to ascertain patient preferences for Personalized Trials.

STUDY DESIGN AND SETTING

We recruited 501 adults with ≥2 common chronic conditions from Harris Poll Online. We used Sawtooth Software to generate 45 plausible Personalized Trial designs comprising combinations of eight key attributes (treatment selection, treatment type, clinician involvement, blinding, time commitment, self-monitoring frequency, duration, and cost) at different levels. Conditional logistic regression was used to assess relative importance of different attributes using a random utility maximization model.

RESULTS

Overall, participants preferred Personalized Trials with no costs vs. $100 cost (utility difference 1.52 [standard error 0.07], P < 0.001) and with less vs. more time commitment/day (0.16 [0.07], P < 0.015) but did not hold preferences for the other six attributes. In subgroup analyses, participants ≥65 years, white, and with income ≤$50,000 were more averse to costs than their counterparts (P all <0.05).

CONCLUSION

To optimize dissemination, Personalized Trial designers should seek to minimize out-of-pocket costs and time burden of self-monitoring. They should also consider adaptive designs that can accommodate subgroup differences in design preferences.

N-of-1 Randomized Trials of Ultra-Micronized Palmitoylethanolamide in Older Patients with Chronic Pain

BACKGROUND

Ultra-micronized palmitoylethanolamide (um-PEA) represents an attractive option for chronic pain control in complex older patients at higher risk of adverse effects with traditional analgesics.

OBJECTIVE

The aim of this study was to determine the effectiveness of um-PEA versus placebo on chronic pain intensity and function in individual geriatric patients.

DESIGN

We performed randomized, blinded N-of-1 trials with two 3-week um-PEA versus placebo comparisons, separated by 2-week washout periods.

PARTICIPANTS

The study included outpatients aged ≥ 65 years with chronic, non-cancer, non-ischemic pain in the back, joints, or limbs.

INTERVENTION

Patients were randomized to Um-PEA 600 mg or placebo twice daily.

MEASUREMENTS

Pain intensity was measured using an 11-point visual numeric scale. Functional impairment was measured using a Back Pain Functional Scale. Impact of each N-of-1 trial was measured on the clinician's intention to treat and confidence.

RESULTS

Ten of 11 eligible patients consented over 7 months [all female, mean age 83.2 years (SD 4.6)]. Three patients interrupted the trial: one had diarrhea (under placebo), one for low adherence, and one for intercurrent pneumonia. A small statistically significant effect in favor of um-PEA was seen at the mixed method analyses in two patients (effect size equal to 8% of the baseline pain). A statistically significant impact on function was found in one patient. After the trial, um-PEA was prescribed to four patients; in two patients the clinician changed their pre-trial intention to treat; the clinician confidence in the treatment plan either increased (5) or remained the same (2).

CONCLUSIONS

Our experience confirmed that N-of-1 trials may help make personalized evidence-based decisions in complex older patients, with special feasibility considerations. CLINICALTRIALS.GOV: NCT02699281.

N-of-1 trials for assessing the effects of deprescribing medications on short-term clinical outcomes in older adults: a systematic review

OBJECTIVES

The objective of this study was to determine the applicability of utilizing the N-of-1 method for deprescribing trials in older adults.

STUDY DESIGN AND SETTING

Systematic review of any human studies conducted in older adults (≥50 years), deprescribing any long-term treatment over less than a year using the N-of-1 trial method was performed. Two authors independently reviewed all articles for eligibility and extracted data. The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Quality assessment of trials was carried out using the Physiotherapy Evidence Database scale.

RESULTS

Six studies were identified and extracted. Trials investigated the efficacy of pharmacological and non-pharmacological therapies for treating diseases. Four trials demonstrated non-significant benefits of treatment, with a significant number of patients discontinuing their medications in two trials where follow-up data was collected (N = 8/18, 9/14 [44.4--64.3%]). In two studies, where treatment was beneficial, all participants were found to be maintaining regimen at follow-up.

CONCLUSION

The N-of-1 trial methodology can be used to generate patient-specific evidence of medication and inform prescribing decisions. Future studies are required to assess the feasibility of using the N-of-1 method to determine the effects of deprescribing medications on short-term outcomes.