Trials and tribulations: current challenges in conducting clinical trials

Enrollment Obstacles in a Randomized Controlled Trial: A Performance Survey of Enrollment in BEST-CLI Sites

BACKGROUND

Although randomized controlled trials (RCTs) provide the most reliable form of scientific evidence, they are challenging to complete because of a variety of enrollment obstacles. We evaluated obstacles in a large RCT by comparing survey results at high-performing sites (HPS) and low-performing sites (LPS).

METHODS

The Best Endovascular versus Best Surgical Therapy in Patients with Critical Limb Ischemia (BEST-CLI) trial is a prospective, pragmatic, multicenter, and multispecialty RCT that will compare clinical outcomes, quality of life, and cost in patients with CLI randomized to surgical bypass or endovascular therapy. BEST-CLI aims to enroll 2100 patients at 160 sites in North America, Europe, and New Zealand. We surveyed the 30 HPS and 30 LPS to assess perceptions of enrollment obstacles. HPS were defined by enrollment of 0.5 subjects or more per month or more than 8 total subjects enrolled. LPS were defined by enrollment of 0.1 subjects per month or only 1 subject total. Responses were compared by site performance status.

RESULTS

There were 22 of 30 (73%) HPS and 14 of 30 (47%) LPS that answered the survey (P = 0.06), including 17 investigators and 31 coordinators. The mean total enrollment and rate of enrollment at HPS and LPS were 12.5 subjects at 1.5 subjects/month and 1.0 subject at 0.1 subjects/month, respectively. The most common barrier to enrollment at HPS was difficulty convincing patients and their families to participate (36%), whereas at LPS both difficulty convincing patients and difficulty motivating investigators to enroll (29% each) were most frequently cited. At HPS, the most common obstacle to consenting patients for the trial was patient/family having strong preference toward revascularization strategy (32%) and at LPS it was patient/family not wanting to have treatment chosen at random (36%). At 55% of HPS and 43% of LPS, the trial team was reported as extremely collaborative (P = 0.73), whereas 68% of HPS and 64% of LPS reported having identified a trial champion on their team (P = 1). The most restrictive perceived enrollment criterion at HPS was prior index limb stenting with significant restenosis (32%), whereas at LPS it was excessive risk for surgical bypass (43%). Materials to aid enrollment were used equally at HPS and LPS: patient brochures at 59% HPS and 64% LPS (P = 1); investigator talking points at 45% of HPS and 36% of LPS (P = 0.73).

CONCLUSIONS

Patient perceptions and investigator biases are significant challenges to enrollment in large RCTs. In the BEST-CLI trial, difficulty convincing patients and families to allow treatment randomization and difficulty in motivating investigators were major enrollment obstacles.

The impact of non-blinding in critical care medicine trials

PURPOSE

It is uncertain whether, in critical care medicine, non-blinded trials are associated with a bias toward a different effect size. The aim of our study was to assess if conducting non-blinded/open label studies leads to greater effect size than blinded studies, and to provide an estimate of the weight of this difference.

MATERIALS AND METHODS

We systematically searched all papers published in peer-reviewed journals between January 2000 and December 2015, dealing with non surgical interventions in critically ill adults and reporting a statistically significant difference in mortality. We assessed the number needed to treat (NNT) of each trial to estimate the treatment effect size and we divided studies into non-blinded, single-blinded and double-blinded. We searched for correlation between the treatment effect size and blinding, and adjusted for the other trial variables.

RESULTS

We identified 119 critically ill randomized controlled trials. Of these, 69 studies were non-blinded and 50 were blinded. The median NNT in non-blinded studies was 5 [IQR 4-7] while it was 7 [IQR 5-7] in the blinded studies (p < .001).

CONCLUSIONS

The NNT for blinded studies is 40% higher than for unblinded studies. This should be taken into account when planning and interpreting the findings of non-blinded studies performed in critically ill settings.

Worldwide trends in volume and quality of published protocols of randomized controlled trials

Introduction

Publishing protocols of randomized controlled trials (RCT) facilitates a more detailed description of study rational, design, and related ethical and safety issues, which should promote transparency. Little is known about how the practice of publishing protocols developed over time. Therefore, this study describes the worldwide trends in volume and methodological quality of published RCT protocols.

Methods

A systematic search was performed in PubMed and EMBASE, identifying RCT protocols published over a decade from 1 September 2001. Data were extracted on quality characteristics of RCT protocols. The primary outcome, methodological quality, was assessed by individual methodological characteristics (adequate generation of allocation, concealment of allocation and intention-to-treat analysis). A comparison was made by publication period (First, September 2001- December 2004; Second, January 2005-May 2008; Third, June 2008-September 2011), geographical region and medical specialty.

Results

The number of published RCT protocols increased from 69 in the first, to 390 in the third period (p<0.0001). Internal medicine and paediatrics were the most common specialty topics. Whereas most published RCT protocols in the first period originated from North America (n = 30, 44%), in the second and third period this was Europe (respectively, n = 65, 47% and n = 190, 48%, p = 0.02). Quality of RCT protocols was higher in Europe and Australasia, compared to North America (OR = 0.63, CI = 0.40–0.99, p = 0.04). Adequate generation of allocation improved with time (44%, 58%, 67%, p = 0.001), as did concealment of allocation (38%, 53%, 55%, p = 0.03). Surgical protocols had the highest quality among the three specialty topics used in this study (OR = 1.94, CI = 1.09–3.45, p = 0.02).

Conclusion

Publishing RCT protocols has become popular, with a five-fold increase in the past decade. The quality of published RCT protocols also improved, although variation between geographical regions and across medical specialties was seen. This emphasizes the importance of international standards of comprehensive training in RCT methodology.

Knowledge translation and implementation in spinal cord injury: a systematic review

OBJECTIVE

To conduct a systematic review examining the effectiveness of knowledge translation (KT) interventions in changing clinical practice and patient outcomes.

METHODS

MEDLINE/PubMed, CINAHL, EMBASE and PsycINFO were searched for studies published from January 1980 to July 2012 that reported and evaluated an implemented KT intervention in spinal cord injury (SCI) care. We reviewed and summarized results from studies that documented the implemented KT intervention, its impact on changing clinician behavior and patient outcomes as well as the facilitators and barriers encountered during the implementation.

RESULTS

A total of 13 articles featuring 10 studies were selected and abstracted from 4650 identified articles. KT interventions included developing and implementing patient care protocols, providing clinician education and incorporating outcome measures into clinical practice. The methods (or drivers) to facilitate the implementation included organizing training sessions for clinical staff, introducing computerized reminders and involving organizational leaders. The methodological quality of studies was mostly poor. Only 3 out of 10 studies evaluated the success of the implementation using statistical analyses, and all 3 reported significant behavior change. Out of the 10 studies, 6 evaluated the effect of the implementation on patient outcomes using statistical analyses, with 4 reporting significant improvements. The commonly cited facilitators and barriers were communication and resources, respectively.

CONCLUSION

The field of KT in SCI is in its infancy with only a few relevant publications. However, there is some evidence that KT interventions may change clinician behavior and improve patient outcomes. Future studies should ensure rigorous study methods are used to evaluate KT interventions.

Blinding of outcomes in trials of orthopaedic trauma: an opportunity to enhance the validity of clinical trials

BACKGROUND

Blinding personnel in randomized controlled trials is an important strategy to minimize bias and increase the validity of the results. Trials of surgical interventions present blinding challenges not seen in drug trials. How often orthopaedic trauma investigators undertake blinding, and the frequency with which they could potentially utilize blinding, remains uncertain.

METHODS

We conducted a systematic review of all randomized controlled trials of orthopaedic trauma published from 1995 to 2004. Two reviewers assessed each trial for eligibility and extracted data regarding its characteristics, outcomes, reporting of blinding, and feasibility of blinding.

RESULTS

We included 171 unique randomized controlled trials spanning a variety of body regions and interventions. The most commonly reported outcomes were clinical (e.g., mortality or wound infection; 91% of trials), radiographic (83%), patient-reported (66%), and physiological results (e.g., range of motion; 56%). Less than 10% of the trials in each category reported the use of blinded outcome assessors. This contrasted with blinding that investigators could have accomplished: blinding was feasible with use of simple methods such as independent assessors, concealed incisions, and masked radiographs for 89% of clinical assessors, 89% of radiographic assessors, 96% of physiological assessors, and 35% of patient-reported assessors.

CONCLUSIONS

Trials in orthopaedic trauma typically measure many outcomes requiring judgment, but the individuals assessing those outcomes are seldom blinded. Investigators have the opportunity to enhance the validity of future clinical trials by incorporating simple blinding techniques.

Oncologic results of laparoscopic versus conventional open surgery for stage II or III left-sided colon cancers: a randomized controlled trial

INTRODUCTION

Minimal invasive surgical approach can achieve quick functional recovery. However, the oncologic outcome for cancer is still a concern. This study aims to compare the oncologic outcome between laparoscopic and open methods in the curative resection of Stage II or III left-sided colon cancers.

METHODS

In consideration of statistical power up to 90%, 286 eligible patients with curable left-sided colon cancer (Tumor-Node-Metastasis Stage II and Stage III disease) requiring the takedown of colonic splenic flexure to facilitate a curative left hemicolectomy were recruited randomly and equally allocated to the laparoscopic and open group. The primary endpoint was time-to-recurrence of tumor. Data was analyzed according to intention-to-treat principle.

RESULTS

Postrandomization exclusion occurred because of metastatic disease detected intraoperatively occurred in 13 patients and because of patient withdrawal from trial in 4. Therefore, 135 and 134 patients actually comprised the laparoscopic and open group, respectively. The median follow-up of patient was 40 months (range: 18-72 months). The oncologic results were similar (P = 0.362, one-sided log-rank test) in laparoscopic and open group of patients, with the estimated cumulative recurrence rate of 13.2% (9/68) versus 17.2% (11/64) in Stage II disease and 20.9% (14/67) versus 25.7% (18/70) in Stage III disease, respectively. The recurrence patterns were similar between the two groups. Both open and laparoscopic groups were comparable in the number of dissected lymph node (15.6 +/- 3.0 vs. 16.0 +/- 6.0, P = 0.489), various demographic and clinicopathologic parameters.

CONCLUSIONS

The estimated cumulative recurrence rate for the surgery of Stage II or III left-sided colon cancers was the same between laparoscopic and open methods.

A randomized controlled trial of laparoscopic versus open cholecystectomy in patients with cirrhotic portal hypertension

AIM: To evaluate the characters, risks and benefits of laparoscopic cholecystectomy (LC) in cirrhotic portal hypertension (CPH) patients.

METHODS: Altogether 80 patients with symptomatic gallbladder disease and CPH, including 41 Child class A, 32 Child class B and 7 Child class C, were randomly divided into open cholecystectomy (OC) group (38 patients) and LC group (42 patients). The cohorts were well-matched for number, age, sex, Child classification and types of disease. Data of the two groups were collected and analyzed.

RESULTS: In LC group, LC was successfully performed in 36 cases, and 2 patients were converted to OC for difficulty in managing bleeding under laparoscope and dense adhesion of Calot’s triangle. The rate of conversion was 5.3%. The surgical duration was 62.6±15.2 min. The operative blood loss was 75.5±15.5 mL. The time to resume diet was 18.3±6.5 h. Seven postoperative complications occurred in five patients (13.2%). All patients were dismissed after an average of 4.6±2.4 d. In OC group, the operation time was 60.5±17.5 min. The operative blood loss was 112.5±23.5 mL. The time to resume diet was 44.2±10.5 h. Fifteen postoperative complications occurred in 12 patients (30.0%). All patients were dismissed after an average of 7.5±3.5 d. There was no significant difference in operation time between OC and LC group. But LC offered several advantages over OC, including fewer blood loss and lower postoperative complication rate, shorter time to resume diet and shorter length of hospitalization in patients with CPH.

CONCLUSION: Though LC for patients with CPH is difficult, it is feasible, relatively safe, and superior to OC. It is important to know the technical characters of the operation, and pay more attention to the meticulous perioperative managements.

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A multicenter clinical trial in the Arab world

Financial, social, and perhaps religious, ethical, and other factors hinder investment and performance of clinical research in Arab countries. We report in that conducting multicenter clinical trials is feasible in the Arab world, describing our experience in planning and conducting one of the first multicenter, multinational, clinical trials in the region. A multicenter clinical trial sought to document the efficacy and safety of Epotin for the treatment of anemia in patients on maintenance hemodialysis. Among 29 centers contacted for participation, a positive response was obtained from 17 (62%) located in eight countries. The initial recruitment period of 3 months was extended to 1 year. Among the participating centers, 16 forwarded their results in time, with one being late. There were minor and a few major protocol violations, the latter requiring exclusion of data from the final analysis. Sponsorship was mainly by a local pharmaceutical company (Julphar). A co-coordinating body was crucial to trace and gather the data. Since conduct of the trial required considerable time and effort from investigators, the use of modern information technology could have reduced the effort and improved the outcomes. We conclude that multicenter clinical trials, which are essential can be conducted in this region. This experience needs to be repeated and refined.