Blinding in trials of interventional procedures is possible and worthwhile

Quality of Randomized Controlled Trials in the Association of Southeast Asian Nations (ASEAN) - A Systematic Review

INTRODUCTION

This study aimed to assess the quality and characteristics of RCTs in the ASEAN Member States (AMS) during a decade of harmonization efforts.

METHODS

This study is a systematic review to assess the quality of RCTs conducted in AMS. Studies were included if they were (1) reports of RCTs involving AMS from 2010 to 2021; (2) published in English; and (3) available in full text. Literature searches were conducted in MEDLINE and EMBASE. Study quality was assessed using the Cochrane's risk-of-bias tool and were classified as high- or low-quality. Multiple logistic regression analysis was used to identify characteristics associated with RCT quality.

RESULTS & DISCUSSIONS

A total of 51,177 articles were identified, among which 437 studies were eligible for quality assessment. Of the 437 studies, 41.6% were of high-quality. The use of blinding and a higher number of participants (100-1000 and > 1000) contributed positively to study quality (odds ratio (OR): 1.60 [95% confidence interval (CI): 1.05-2.41]; OR: 1.91 [95%CI: 1.24-2.94]; OR: 3.14 [95%CI: 1.22-8.10], respectively). Whereas the use of non-parallel assignment in the type of randomization contributed negatively to study quality (OR: 0.51 [95% CI: 0.26-1.03], P = 0.060). Among the six AMS with a high number of RCTs, two had high-quality studies > 50%, three had slightly more than 40% and one had less than 20%.

CONCLUSIONS

In the decade of regulatory harmonization, less than half of RCTs in AMS were of high-quality. Large numbers of participants and the use of blinding were associated with high-quality RCTs, while the opposite was true for studies with non-parallel assignment. To improve the quality of RCTs, more training and capacity building of local researchers is needed, with particular attention to study design.

One-food versus 4-food elimination diet for pediatric eosinophilic esophagitis: A multisite randomized trial

BACKGROUND

A 6-food elimination diet in pediatric eosinophilic esophagitis (EoE) is difficult to implement and may negatively affect quality of life (QoL). Less restrictive elimination diets may balance QoL and efficacy.

OBJECTIVE

We performed a multisite, randomized comparative efficacy trial of a 1-food (milk) elimination diet (1FED) versus 4-food (milk, egg, wheat, soy) elimination diet (4FED) in pediatric EoE.

METHODS

Patients aged 6 to 17 years with histologically active and symptomatic EoE were randomized 1:1 to 1FED or 4FED for 12 weeks. Primary end point was symptom improvement by Pediatric Eosinophilic Esophagitis Symptom Score (PEESS). Secondary end points were proportion experiencing histologic remission (<15 eosinophils per high-power field); change in histologic features (histology scoring system), endoscopic severity (endoscopic reference score), transcriptome (EoE diagnostic panel), and QoL scores; and predictors of remission.

RESULTS

Sixty-three patients were randomly assigned to 1FED (n = 38) and 4FED (n = 25). In 4FED versus 1FED, mean PEESS improved -25.0 versus -14.5 (P = .04), but remission rates (41% vs 44%; P = 1.00), histology scoring system (-0.25 vs -0.29; P = .77), endoscopic reference score (-1.10 vs -0.58; P = .47), and QoL scores were similar between groups. The EoE transcriptome normalized in those with histologic response to both diets. Baseline peak eosinophil count predicted remission (odds ratio, 0.975 [95% confidence interval, 0.953-0.999], P = .04; cutoff ≤42 eosinophils per high-power field). The 4FED withdrawal rate (32%) exceeded that of 1FED (11%) (P = .0496).

CONCLUSIONS

Although 4FED moderately improved symptoms compared with 1FED, the histologic, endoscopic, QoL, and transcriptomic outcomes were similar in both groups. 1FED is a reasonable first-choice therapy for pediatric EoE, given its effects, tolerability, and relative simplicity.

Large simple randomized controlled trials-from drugs to medical devices: lessons from recent experience

Randomized controlled trials (RCTs) are the cornerstone of modern evidence-based medicine. They are considered essential to establish definitive evidence of efficacy and safety for new drugs, and whenever possible they should also be the preferred method for investigating new high-risk medical devices. Well-designed studies robustly inform clinical practice guidelines and decision-making, but administrative obstacles have made it increasingly difficult to conduct informative RCTs. The obstacles are compounded for RCTs of high-risk medical devices by extra costs related to the interventional procedure that is needed to implant the device, challenges with willingness to randomize patients throughout a trial, and difficulties in ensuring proper blinding even with sham procedures. One strategy that may help is to promote the wider use of simpler and more streamlined RCTs using data that are collected routinely during healthcare delivery. Recent large simple RCTs have successfully compared the performance of drugs and of high-risk medical devices, against alternative treatments; they enrolled many patients in a short time, limited costs, and improved efficiency, while also achieving major impact. From a task conducted within the CORE-MD project, we report from our combined experience of designing and conducting large pharmaceutical trials during the COVID-19 pandemic, and of planning and coordinating large registry-based RCTs of cardiovascular devices. We summarize the essential principles and utility of large simple RCTs, likely applicable to all interventions but especially in order to promote their wider adoption to evaluate new medical devices.

The Effect of Self-efficacy-Enhancing Interventions on Quality of Life of Cancer Survivors: A Systematic Review

BACKGROUND

The influence of self-efficacy-enhancing interventions on quality of life (QOL) is not clear with recent randomized controlled trials (RCTs) because current reviews only evaluated self-efficacy as an outcome.

OBJECTIVES

We conducted a systematic review to examine the effect of self-efficacy-enhancing interventions on QOL among patients with cancer and to summarize the effective determinants for designing self-efficacy-enhancing interventions.

METHODS

A systematic search was performed on studies published from January 2003 to May 2023 using PubMed, CINAHL, PsycINFO, and Web of Science. Included studies were RCTs, adults diagnosed with cancer, interventions with explicit self-efficacy components, and QOL as the outcome.

RESULTS

Nineteen RCTs were included. Risk-of-bias assessment revealed 12 studies with some concerns and 7 with high risk of bias. The mean intervention adherence rate was 88.2%; the most frequently listed reason for dropout was medical conditions and mortality. Self-efficacy interventions were shown to significantly improve at least 1 subscale of QOL in 9 of 19 studies, of which 7 studies used Bandura's 4 sources of self-efficacy. The interventions with between-session intervals shorter than 2 weeks, of 12-week duration, and with an in-person delivery approach were the most effective.

CONCLUSIONS

Self-efficacy-enhancing interventions show potential beneficial effects on QOL among cancer survivors. Interventions that use Bandura's 4 sources of self-efficacy strategies and have between-session intervals shorter than 2 weeks, an in-person approach, and 12-week intervention duration are recommended.

IMPLICATIONS FOR PRACTICE

Properly designed self-efficacy-enhancing interventions can facilitate behavioral change and improve QOL in cancer survivors.

Success of blinding a procedural intervention in a randomised controlled trial in preterm infants receiving respiratory support

BACKGROUND

Blinding of treatment allocation from treating clinicians in neonatal randomised controlled trials can minimise performance bias, but its effectiveness is rarely assessed.

METHODS

To examine the effectiveness of blinding a procedural intervention from treating clinicians in a multicentre randomised controlled trial of minimally invasive surfactant therapy versus sham treatment in preterm infants of gestation 25-28 weeks with respiratory distress syndrome. The intervention (minimally invasive surfactant therapy or sham) was performed behind a screen within the first 6 h of life by a 'study team' uninvolved in clinical care including decision-making. Procedure duration and the study team's words and actions during the sham treatment mimicked those of the minimally invasive surfactant therapy procedure. Post-intervention, three clinicians completed a questionnaire regarding perceived group allocation, with the responses matched against actual intervention and categorised as correct, incorrect, or unsure. Success of blinding was calculated using validated blinding indices applied to the data overall (James index, successful blinding defined as > 0.50), or to the two treatment allocation groups (Bang index, successful blinding: -0.30 to 0.30). Blinding success was measured within staff role, and the associations between blinding success and procedural duration and oxygenation improvement post-procedure were estimated.

RESULTS

From 1345 questionnaires in relation to a procedural intervention in 485 participants, responses were categorised as correct in 441 (33%), incorrect in 142 (11%), and unsure in 762 (57%), with similar proportions for each of the response categories in the two treatment arms. The James index indicated successful blinding overall 0.67 (95% confidence interval (CI) 0.65-0.70). The Bang index was 0.28 (95% CI 0.23-0.32) in the minimally invasive surfactant therapy group and 0.17 (95% CI 0.12-0.21) in the sham arm. Neonatologists more frequently guessed the correct intervention (47%) than bedside nurses (36%), neonatal trainees (31%), and other nurses (24%). For the minimally invasive surfactant therapy intervention, the Bang index was linearly related to procedural duration and oxygenation improvement post-procedure. No evidence of such relationships was seen in the sham arm.

CONCLUSION

Blinding of a procedural intervention from clinicians is both achievable and measurable in neonatal randomised controlled trials.

Blinding and sham control methods in trials of physical, psychological, and self-management interventions for pain (article I): a systematic review and description of methods

ABSTRACT

Blinding is challenging in randomised controlled trials of physical, psychological, and self-management therapies for pain, mainly because of their complex and participatory nature. To develop standards for the design, implementation, and reporting of control interventions in efficacy and mechanistic trials, a systematic overview of currently used sham interventions and other blinding methods was required. Twelve databases were searched for placebo or sham-controlled randomised clinical trials of physical, psychological, and self-management treatments in a clinical pain population. Screening and data extraction were performed in duplicate, and trial features, description of control methods, and their similarity to the active intervention under investigation were extracted (protocol registration ID: CRD42020206590). The review included 198 unique control interventions, published between 2008 and December 2021. Most trials studied people with chronic pain, and more than half were manual therapy trials. The described control interventions ranged from clearly modelled based on the active treatment to largely dissimilar control interventions. Similarity between control and active interventions was more frequent for certain aspects (eg, duration and frequency of treatments) than others (eg, physical treatment procedures and patient sensory experiences). We also provide an overview of additional, potentially useful methods to enhance blinding, as well as the reporting of processes involved in developing control interventions. A comprehensive picture of prevalent blinding methods is provided, including a detailed assessment of the resemblance between active and control interventions. These findings can inform future developments of control interventions in efficacy and mechanistic trials and best-practice recommendations.

Is laparoscopic excision for superficial peritoneal endometriosis helpful or harmful? Protocol for a double-blinded, randomised, placebo-controlled, three-armed surgical trial

INTRODUCTION

Placebo-controlled surgical designs are recommended to ascertain treatment effects for elective surgeries when there is genuine doubt about the effectiveness of the surgery. Some elective surgeries for pain have been unable to show an effect beyond sham surgery, suggesting contributions from contextual factors. However, the nature of contextual factors in elective surgery is largely unexplored. Further, methodological difficulties in placebo-controlled surgical trials impact the ability to estimate the effectiveness of a surgical procedure. These include an overall lack of testing the success of blinding, absence of comparison to a no-surgery control group and dearth of test for neuropathic pain.For women with peritoneal endometriosis, there is uncertainty regarding the pain-relieving effect of surgery. Surgery may put patients at risk of complications such as postsurgical neuropathic pain, without guarantees of sufficient pelvic pain relief. The planned placebo-controlled trial aims to examine the effect of surgery on pelvic pain, widespread pain and neuropathic pain symptoms in women with peritoneal endometriosis, and to test the contribution of contextual factors to pain relief.

METHODS AND ANALYSIS

One hundred women with peritoneal endometriosis will be randomised to either diagnostic laparoscopy with excision of endometrial tissue (active surgery), purely diagnostic laparoscopy (sham surgery) or delayed surgery (no-surgery control group). Outcomes include pelvic pain relief, widespread pain, neuropathic pain symptoms and quality of life. Contextual factors are also assessed. Assessments will be obtained at baseline and 1, 3 and 6 months postrandomisation. Mixed linear models will be used to compare groups over time on all outcome variables.

ETHICS AND DISSEMINATION

The trial is approved by the Regional Ethics Committee in the Central Denmark Region (1-10-72-152-20). The trial is funded by a PhD scholarship from Aarhus University, and supported by a grant from 'Helsefonden' (20-B-0448). Findings will be published in international peer-reviewed journals and disseminated at international conferences.

TRIAL REGISTRATION NUMBER

NCT05162794.

Mortality associated with cemented and uncemented fixation of hemiarthroplasty and total hip replacement in the surgical management of intracapsular hip fractures: A systematic review and meta-analysis

BACKGROUND

The use of bone cement for implant fixation in the surgical management of intracapsular hip fractures (IHFs) remains controversial. Although UK national guidance supports cementation, many surgeons remain cautious of its use. In this systematic review and meta-analysis, we aimed to evaluate evidence surrounding post-operative mortality associated with cemented and uncemented total hip replacement and hemiarthroplasty implants.

METHODS

We conducted a search of MEDLINE and Embase databases for randomised controlled trials (RCTs) from commencement until 17 June 2020. Articles reporting mortality or patient survival as an outcome following total hip replacement (THR) or hemiarthroplasty (HA) to manage IHFs were included. Articles not comparing cemented and uncemented fixation were excluded. A meta-analysis on mortality stratified by post-operative follow-up period was conducted using a fixed-effects model. The Revised Cochrane risk-of-bias tool for randomized trials was used to assess risk of bias.

RESULTS

Our initial search found 77 references, 13 of which were eligible for full-text review. Mortality data from 12 studies were pooled and included in the meta-analysis. 1 599 operations were reported: 882 involved cemented fixation; 717, uncemented. Mortality outcome reporting ranged from less than 7 days to 5 years post-operation. No significant difference was observed between the two groups in mortality at any follow-up period. Study quality assessment revealed low certainty in mortality estimates.

CONCLUSION

Existing evidence indicates that cementation has no effect on mortality at any reported follow-up time period. Even with the use of evidence synthesis, the sample size remains relatively low for mortality outcomes and insufficiently powered to reliably determine differences between groups.

Blinding in Clinical Trials: Seeing the Big Picture

Blinding mitigates several sources of bias which, if left unchecked, can quantitively affect study outcomes. Blinding remains under-utilized, particularly in non-pharmaceutical clinical trials, but is often highly feasible through simple measures. Although blinding is generally viewed as an effective method by which to eliminate bias, blinding does also pose some inherent limitations, and it behooves clinicians and researchers to be aware of such caveats. This article will review general principles for blinding in clinical trials, including examples of useful blinding techniques for both pharmaceutical and non-pharmaceutical trials, while also highlighting the limitations and potential consequences of blinding. Appropriate reporting on blinding in trial protocols and manuscripts, as well as future directions for blinding research, will also be discussed.

Mental Skills Training and Resident Surgical Outcomes: A Systematic Review

OBJECTIVE

Mental skills training (MST) in surgical education varies greatly in quality and outcomes. This systematic review assessed the effectiveness of MST on surgical trainee performance in simulated and operating room (OR) settings.

DESIGN

We searched PubMed/MEDLINE, EMBASE, and PsycINFO for randomized controlled trials using Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Peer-reviewed studies published in the English language between January 1, 2000 and March 1, 2020 were considered for inclusion. Articles that did not study surgical residents, assess surgical performance as an outcome, or report findings were excluded. Study characteristics, methodologies, and outcomes were qualitatively analyzed. Grading of Recommendations, Assessment, Development and Evaluations (GRADE) was used to measure the quality of the studies, and the Oxford quality scoring system for risk of bias ratings.

RESULTS

Seven randomized controlled trials met study inclusion criteria; interventions were mental practice, relaxation exercises, action observation, and Mindfulness-Based Stress Reduction. Targeted interventions based on mental practice, relaxation exercises, and MBSR significantly improved surgical performance in four (57%) studies. Risk of bias was low for all included studies, and quality of evidence was moderate for both simulated and OR performance.

CONCLUSIONS

Mental practice, relaxation, and mindfulness training improved simulation and OR performance for surgical residents. There was insufficient evidence to support other MST interventions or the intermediate- and long-term efficacy of MST.

Optimizing the design of invasive placebo interventions in randomized controlled trials

Background

Placebo‐controlled trials play an important role in the evaluation of healthcare interventions. However, they can be challenging to design and deliver for invasive interventions, including surgery. In‐depth understanding of the component parts of the treatment intervention is needed to ascertain what should, and should not, be delivered as part of the placebo. Assessment of risk to patients and strategies to ensure that the placebo effectively mimics the treatment are also required. To date, no guidance exists for the design of invasive placebo interventions. This study aimed to develop a framework to optimize the design and delivery of invasive placebo interventions in RCTs.

Methods

A preliminary framework was developed using published literature to: expand the scope of an existing typology, which facilitates the deconstruction of invasive interventions; and identify placebo optimization strategies. The framework was refined after consultation with key stakeholders in surgical trials, consensus methodology and medical ethics.

Results

The resulting DITTO framework consists of five stages: deconstruct treatment intervention into constituent components and co‐interventions; identify critical surgical element(s); take out the critical element(s); think risk, feasibility and role of placebo in the trial when considering remaining components; and optimize placebo to ensure effective blinding of patients and trial personnel.

Conclusion

DITTO considers invasive placebo composition systematically, accounting for risk, feasibility and placebo optimization. Use of the framework can support the design of high‐quality RCTs, which are needed to underpin delivery of healthcare interventions.

Reporting of key methodological issues in placebo-controlled trials of surgery needs improvement: a systematic review

OBJECTIVES

To examine key methodological considerations for using a placebo intervention in randomized controlled trials (RCTs) evaluating invasive procedures, including surgery.

STUDY DESIGN AND SETTING

RCTs comparing an invasive procedure with a placebo were included in this systematic review. Articles published from database inception to December 31, 2017, were retrieved from Ovid MEDLINE, Ovid EMBASE and CENTRAL electronic databases, by handsearching references and expert knowledge. Data on trial characteristics (clinical area, nature of invasive procedure, number of patients and centers) and key methodological (rationale for using placebos, minimization of risk, information provision, offering the treatment intervention to patients randomized to placebo, delivery of cointerventions, and intervention standardization and fidelity) were extracted and summarized descriptively.

RESULTS

One hundred thirteen articles reporting 96 RCTs were identified. Most were conducted in gastrointestinal surgery (n = 40, 42%) and evaluated minimally invasive procedures (n = 44, 46%). Over two-thirds randomized fewer than 100 patients (n = 65, 68%) and a third were single center (n = 31, 32%). A third (n = 33, 34%) did not report a rationale for using a placebo. Most common strategies to minimize patient risk were operator skill (n = 22, 23%) and independent data monitoring (n = 28, 29%). Provision of patient information regarding placebo use was infrequently reported (n = 11, 11%). Treatment interventions were offered to patients randomized to placebo in 43 trials (45%). Cointerventions were inconsistently reported, but 64 trials (67%) stated that anesthesia was matched between groups. Attempts to standardize interventions and monitor their delivery were reported in n = 7, (7%) and n = 4, (4%) trials, respectively.

CONCLUSION

Most placebo-controlled trials in surgery evaluate minor surgical procedures and currently there is inconsistent reporting of key trial methods. There is a need for guidance to optimize the transparency of trial reporting in this area.

Study protocol for VIdeo assisted thoracoscopic lobectomy versus conventional Open LobEcTomy for lung cancer, a UK multicentre randomised controlled trial with an internal pilot (the VIOLET study)

INTRODUCTION

Lung cancer is a leading cause of cancer deaths worldwide and surgery remains the main treatment for early stage disease. Prior to the introduction of video-assisted thoracoscopic surgery (VATS), lung resection for cancer was undertaken through an open thoracotomy. To date, the evidence base supporting the different surgical approaches is based on non-randomised studies, small randomised trials and is focused mainly on short-term in-hospital outcomes.

METHODS AND ANALYSIS

The VIdeo assisted thoracoscopic lobectomy versus conventional Open LobEcTomy for lung cancer study is a UK multicentre parallel group randomised controlled trial (RCT) with blinding of outcome assessors and participants (to hospital discharge) comparing the effectiveness, cost-effectiveness and acceptability of VATS lobectomy versus open lobectomy for treatment of lung cancer. We will test the hypothesis that VATS lobectomy is superior to open lobectomy with respect to self-reported physical function 5 weeks after randomisation (approximately 1 month after surgery). Secondary outcomes include assessment of efficacy (hospital stay, pain, proportion and time to uptake of chemotherapy), measures of safety (adverse health events), oncological outcomes (proportion of patients upstaged to pathologic N2 (pN2) disease and disease-free survival), overall survival and health related quality of life to 1 year. The QuinteT Recruitment Intervention is integrated into the trial to optimise recruitment.

ETHICS AND DISSEMINATION

This trial has been approved by the UK (Dulwich) National Research Ethics Service Committee London. Findings will be written-up as methodology papers for conference presentation, and publication in peer-reviewed journals. Many aspects of the feasibility work will inform surgical RCTs in general and these will be reported at methodology meetings. We will also link with lung cancer clinical studies groups. The patient and public involvement group that works with the Respiratory Biomedical Research Unit at the Brompton Hospital will help identify how we can best publicise the findings.

TRIAL REGISTRATION NUMBER

ISRCTN13472721.