Design and analysis of stratified clinical trials in the presence of bias

Efficacy of acupuncture (Jin's three-needle) on motor symptoms and anxiety in patients with Parkinson's disease: protocol for a multicentre, randomised, assessor-blinded clinical trial

INTRODUCTION

Parkinson's disease (PD) has a significant impact on a substantial number of individuals in China. Notably, 31% of patients with PD also grapple with the additional burden of anxiety. This dual challenge of managing both PD and anxiety underscores the complexity of the condition and the diverse range of symptoms patients may experience. Considering the circumstances, the cost and potential drawbacks associated with traditional antiparkinsonian drugs become increasingly relevant. Acupuncture emerges as a significant non-pharmacological adjunct therapy. Offering a potentially safer and more cost-effective option, acupuncture addresses the pressing need for holistic and complementary treatments that may alleviate both the motor symptoms of PD and the accompanying anxiety.

METHODS AND ANALYSIS

This is a multicentre, randomised controlled and assessor-blind trial. A total of 210 eligible patients with PD will be randomly assigned (1:1) to Jin's three-needle (JTN) acupuncture group or waitlist (WL) group. Patients in the JTN group will receive acupuncture therapy three times per week for 4 weeks. Patients in the WL group will maintain their original dosage of antiparkinsonian drugs and receive acupuncture therapy after the observation period. The primary outcome measure will be the Unified Parkinson's Disease Rating Scale score. The secondary outcome measures will be the scores of the Hoehn-Yahr Rating Scale, Unified Dyskinesia Rating Scale, Non-Motor Symptoms Scale, 39-item Parkinson's Disease Questionnaire, Parkinson Anxiety Scale, Hamilton Anxiety Scale, Hamilton Depression Scale, Zarit burden interview and the level of cortisol and adrenocorticotropic hormone. The evaluation will be executed at baseline, the end of the treatment and a follow-up period.

ETHICS AND DISSEMINATION

The study was approved by the Ethics Committee of the First Affiliated Hospital of Guangzhou University of Chinese Medicine (K[2023]014). All patients have to provide written, informed consent. The study will be disseminated through presentations in peer-reviewed international journals and at national and international conferences.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry; ChiCTR2300074675.

The effect of cognitive-behavioral therapy and haptonomy on fear of childbirth in primigravida women: a randomized clinical trial

BACKGROUND

Considering the role of fear of childbirth (FOC) in the enhancement of unnecessary cesarean sections (CS), the present study aimed at evaluating the effect of Cognitive-Behavioral Therapy (CBT) and haptonomy on the FOC (as primary outcome) and intended birth method and final birth method (as secondary outcomes) among primigravida women.

METHODS

This randomized clinical trial was conducted on 99 primigravida women in Tabriz, Iran 2022. Participants were assigned to three groups with a ratio of 1:1:1 using stratified block randomization based on the fear intensity. One of the intervention groups (n = 33) received eight group sessions of CBT from 24 to 28 weeks of gestation and the other intervention group (n = 33) received haptonomy during seven sessions once a week. The control group (n = 33) received routine prenatal care. The Wijma questionnaire was completed by the participants before the intervention, after the intervention at 35-37 weeks of gestation, and after birth. The intended birth method was investigated before and after the intervention at 35-37 weeks of gestation. The final birth method and the reasons for CS were recorded based on the mother's medical profile. The one-way ANOVA was used before the intervention and RMANOVA after the intervention to compare the mean scores of FOC among the three groups. Further, chi-square test was applied to compare the intended and final birth method.

RESULTS

The mean (standard deviation: SD) of FOC in the CBT group changed from 74.09 (11.35) at 24-28 weeks of gestation to 46.50 (18.28) at 35-37 weeks and 48.78 (20.64) after birth (P < 0.001). The means (SDs) of FOC in the haptonomy group were 76.81 (13.09), 46.59 (15.81), and 45.09 (20.11), respectively (P < 0.001). The mean (SD) of FOC in the control group decreased from 70.31 (6.71) to 66.56 (18.92) and then, increased to 71.00 (21.14) after birth (P = 0.878). After the intervention, there was no statistically significant difference among the three groups in terms of the intended birth method (P = 0.278), and final birth method (P = 0.107).

CONCLUSION

The findings of the present study revealed that both CBT and haptonomy interventions reduce FOC. Although the desire for vaginal birth and final vaginal birth in the haptonomy group was more than that in the other two groups, there was no statistically significant difference among the three groups.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials: IRCT20170506033834N9. Date of registration: 02.01.2022. URL: http://en.irct.ir .

The effectiveness of cognitive behavioral therapy-based group counseling on depressive symptomatology, anxiety levels, automatic thoughts, and coping ways Turkish nursing students: A randomized controlled trial

PURPOSE

This study aimed to evaluate the effectiveness of cognitive behavioral therapy (CBT)-based group counseling focused on depressive symptoms, anxiety levels, automatic thoughts, and coping ways among undergraduate nursing students with mild to moderate depressive symptoms.

DESIGN AND METHODS

A randomized, nonblinded, controlled trial was conducted. The study was completed with a total of 63 participants (n = 31, intervention group; n = 32, control group). The effect of the intervention was evaluated with Beck depression inventory, Beck anxiety inventory, automatic thoughts questionnaire, and ways of coping questionnaire. The measurements were taken three times: pretest, posttest, and 2-months posttest.

FINDINGS

CBT-based group counseling was found to reduce depressive symptoms, automatic thoughts, and ineffective coping with stress and to increase effective coping with stress. In both groups, 2-months posttest mean anxiety score was lower than the pre-test mean score.

PRACTICE IMPLICATIONS

CBT-based group counseling reduced depressive symptoms, automatic thoughts, and emotion-focused/ineffective ways for coping with stress.

Transcranial Electrical Stimulation for Relief of Peripartum Mental Health Disorders in Women Undergoing Cesarean Section With Combined Spinal-Epidural Anesthesia: A Pilot Randomized Clinical Trial

OBJECTIVE

This study aimed to explore transcranial electrical stimulation (tES) to relieve peripartum anxiety and depressive symptoms in women undergoing cesarean section with combined spinal-epidural anesthesia.

METHODS

This double-blind, randomized, sham-controlled trial was conducted in the Affiliated Hospital of Xuzhou Medical University from March 2021 and May 2021. One hundred and forty-eight full-term parturients giving birth by elective cesarean section were selected, and 126 were included in the intent-to-treat analysis. Parturients were provided standardized anesthesia and randomized to the active-tES (a-tES) group and sham-tES group. Parturients and outcome assessors were blinded to treatment allocation. The primary outcome was the changes in peripartum mental health disorders, including anxiety, assessed by the Pregnancy-Related Anxiety Questionnaire-Revised 2 (PRAQ-R2). Secondary outcomes included peripartum depressive symptoms, assessed by the Edinburgh Postnatal Depression Scale (EPDS), maternal satisfaction, fatigue level, sleep quality index, and pain score during and after operation. Data were collected before entering the operating room (T0), between post-anesthesia and pre-surgery (T1), before leaving the operating room (T2), and at 24 h post-surgery (T3).

RESULTS

One hundred and twenty-six eligible parturients were enrolled in the two groups: a-tES group (N = 62) and sham-tES group (N = 64). Treatment with tES resulted in significantly lower scores of anxiety compared with sham-tES (T2: P < 0.001; T3: P = 0.001). Moreover, the a-tES groups showed a significant reduction in depression scores (T2: P = 0.003; T3: P = 0.032).

CONCLUSION

In this randomized pilot study, tES treatment is efficacious in alleviating peripartum anxiety and depressive symptoms in women undergoing cesarean section and has been demonstrated to be a novel strategy for improving peripartum mental health disorders.

CLINICAL TRIAL REGISTRATION

[www.chictr.org.cn], identifier [ChiCTR2000040963].

Designing Clinical Trials in Wilson's Disease

BACKGROUND AND AIMS

Wilson's disease (WD) is an autosomal-recessive disorder caused by ATP7B gene mutations leading to pathological accumulation of copper in the liver and brain. Adoption of initial treatments for WD was based on empirical observations. These therapies are effective, but there are still unmet needs for which treatment modalities are being developed. An increase of therapeutical trials is anticipated.

APPROACH AND RESULTS

The first Wilson Disease Aarhus Symposium (May 2019) included a workshop on randomized clinical trial design. The authors of the article were organizers or presented during this workshop, and this article presents their consensus on the design of clinical trials for WD, addressing trial population, treatment comparators, inclusion and exclusion criteria, and treatment endpoints. To achieve adequate recruitment of patients with this rare disorder, the study groups should include all clinical phenotypes and treatment-experienced as well as treatment-naïve patients.

CONCLUSIONS

The primary study endpoint should be clinical or a composite endpoint until appropriate surrogate endpoints are validated. Standardization of clinical trials will permit pooling of data and allow for better treatment comparisons, as well as reduce the future numbers of patients needed per trial.

Clinical trial recruiters' experiences working with trial eligibility criteria: results of an exploratory, cross-sectional, online survey in the UK

BACKGROUND

Eligibility criteria are a fundamental element of clinical trial design, defining who can and who should not participate in a trial. Problems with the design or application of criteria are known to occur and pose risks to participants' safety and trial integrity, sometimes also negatively impacting on trial recruitment and generalisability. We conducted a short, exploratory survey to gather evidence on UK recruiters' experiences interpreting and applying eligibility criteria and their views on how criteria are communicated and developed.

METHODS

Our survey included topics informed by a wider programme of work at the Clinical Trials Research Unit, University of Leeds, on assuring eligibility criteria quality. Respondents were asked to answer based on all their trial experience, not only on experiences with our trials. The survey was disseminated to recruiters collaborating on trials run at our trials unit, and via other mailing lists and social media. The quantitative responses were descriptively analysed, with inductive analysis of free-text responses to identify themes.

RESULTS

A total of 823 eligible respondents participated. In total, 79% of respondents reported finding problems with eligibility criteria in some trials, and 9% in most trials. The main themes in the types of problems experienced were criteria clarity (67% of comments), feasibility (34%), and suitability (14%). In total, 27% of those reporting some level of problem said these problems had led to patients being incorrectly included in trials; 40% said they had led to incorrect exclusions. Most respondents (56%) reported accessing eligibility criteria mainly in the trial protocol. Most respondents (74%) supported the idea of recruiter review of eligibility criteria earlier in the protocol development process.

CONCLUSIONS

Our survey corroborates other evidence about the existence of suboptimal trial eligibility criteria. Problems with clarity were the most often reported, but the number of comments on feasibility and suitability suggest some recruiters feel eligibility criteria and associated assessments can hinder recruitment to trials. Our proposal for more recruiter involvement in protocol development has strong support and some potential benefits, but questions remain about how best to implement this. We invite other trialists to consider our other suggestions for how to assure quality in trial eligibility criteria.

A roadmap to using randomization in clinical trials

BACKGROUND

Randomization is the foundation of any clinical trial involving treatment comparison. It helps mitigate selection bias, promotes similarity of treatment groups with respect to important known and unknown confounders, and contributes to the validity of statistical tests. Various restricted randomization procedures with different probabilistic structures and different statistical properties are available. The goal of this paper is to present a systematic roadmap for the choice and application of a restricted randomization procedure in a clinical trial.

METHODS

We survey available restricted randomization procedures for sequential allocation of subjects in a randomized, comparative, parallel group clinical trial with equal (1:1) allocation. We explore statistical properties of these procedures, including balance/randomness tradeoff, type I error rate and power. We perform head-to-head comparisons of different procedures through simulation under various experimental scenarios, including cases when common model assumptions are violated. We also provide some real-life clinical trial examples to illustrate the thinking process for selecting a randomization procedure for implementation in practice.

RESULTS

Restricted randomization procedures targeting 1:1 allocation vary in the degree of balance/randomness they induce, and more importantly, they vary in terms of validity and efficiency of statistical inference when common model assumptions are violated (e.g. when outcomes are affected by a linear time trend; measurement error distribution is misspecified; or selection bias is introduced in the experiment). Some procedures are more robust than others. Covariate-adjusted analysis may be essential to ensure validity of the results. Special considerations are required when selecting a randomization procedure for a clinical trial with very small sample size.

CONCLUSIONS

The choice of randomization design, data analytic technique (parametric or nonparametric), and analysis strategy (randomization-based or population model-based) are all very important considerations. Randomization-based tests are robust and valid alternatives to likelihood-based tests and should be considered more frequently by clinical investigators.

Including non-concurrent control patients in the analysis of platform trials: is it worth it?

Background

Platform trials allow adding new experimental treatments to an on-going trial. This feature is attractive to practitioners due to improved efficiency. Nevertheless, the operating characteristics of a trial that adds arms have not been well-studied. One controversy is whether just the concurrent control data (i.e. of patients who are recruited after a new arm is added) should be used in the analysis of the newly added treatment(s), or all control data (i.e. non-concurrent and concurrent).

Methods

We investigate the benefits and drawbacks of using non-concurrent control data within a two-stage setting. We perform simulation studies to explore the impact of a linear and a step trend on the inference of the trial. We compare several analysis approaches when one includes all the control data or only concurrent control data in the analysis of the newly added treatment.

Results

When there is a positive trend and all the control data are used, the marginal power of rejecting the corresponding hypothesis and the type one error rate can be higher than the nominal value. A model-based approach adjusting for a stage effect is equivalent to using concurrent control data; an adjustment with a linear term may not guarantee valid inference when there is a non-linear trend.

Conclusions

If strict error rate control is required then non-concurrent control data should not be used; otherwise it may be beneficial if the trend is sufficiently small. On the other hand, the root mean squared error of the estimated treatment effect can be improved through using non-concurrent control data.

Dealing with Possible Baseline Inequalities Between Experimental Groups - The Case of Motor Learning

One important concept of experimental design is the random assignment of participants to experimental groups. This randomization process is used to prevent selection bias, as well as to provide a strong basis for a cause-and-effect relationship between the independent variable/s and the dependent variable/s. In small sample sizes, simple randomization may not provide equal groups at baseline for one or more of the variables, and therefore more restricted types of randomization, such as the stratified permuted-block randomization, can be used. A code was written to calculate the probability that simple randomization will not lead to equality between groups at baseline, and then an example of stratified permuted-block randomization was examined. The findings suggest that for certain variables that are commonly measured in experiments in motor learning, there is a relatively high probability that groups will not be equal at baseline after simple randomization. This observation reflects the small sample sizes usually found in the literature on motor learning. However, stratified permuted-block randomization does lead to greater equality among groups. Implications for researchers are discussed, and a flowchart is proposed that will allow researchers to decide whether to use simple or stratified randomization.