Guidance for Modifying the Definition of Diseases: A Checklist

IMPORTANCE

No guidelines exist currently for guideline panels and others considering changes to disease definitions. Panels frequently widen disease definitions, increasing the proportion of the population labeled as unwell and potentially causing harm to patients. We set out to develop a checklist of issues, with guidance, for panels to consider prior to modifying a disease definition.

OBSERVATIONS

We assembled a multidisciplinary, multicontinent working group of 13 members, including members from the Guidelines International Network, Grading of Recommendations Assessment, Development and Evaluation working group, and the World Health Organisation. We used a 5-step process to develop the checklist: (1) a literature review of issues, (2) a draft outline document, (3) a Delphi process of feedback on the list of issues, (4) a 1-day face-to-face meeting, and (5) further refinement of the checklist. The literature review identified 12 potential issues. From these, the group developed an 8-item checklist that consisted of definition changes, number of people affected, trigger, prognostic ability, disease definition precision and accuracy, potential benefits, potential harms, and the balance between potential harms and benefits. The checklist is accompanied by an explanation of each item and the types of evidence to assess each one. We used a panel's recent consideration of a proposed change in the definition of gestational diabetes mellitus (GDM) to illustrate use of the checklist.

CONCLUSIONS AND RELEVANCE

We propose that the checklist be piloted and validated by groups developing new guidelines. We anticipate that the use of the checklist will be a first step to guidance and better documentation of definition changes prior to introducing modified disease definitions.

Application of minimal important differences in degenerative knee disease outcomes: a systematic review and case study to inform BMJ Rapid Recommendations

OBJECTIVES

To identify the most credible anchor-based minimal important differences (MIDs) for patient important outcomes in patients with degenerative knee disease, and to inform BMJ Rapid Recommendations for arthroscopic surgery versus conservative management DESIGN: Systematic review.

OUTCOME MEASURES

Estimates of anchor-based MIDs, and their credibility, for knee symptoms and health-related quality of life (HRQoL).

DATA SOURCES

MEDLINE, EMBASE and PsycINFO.

ELIGIBILITY CRITERIA

We included original studies documenting the development of anchor-based MIDs for patient-reported outcomes (PROs) reported in randomised controlled trials included in the linked systematic review and meta-analysis and judged by the parallel BMJ Rapid Recommendations panel as critically important for informing their recommendation: measures of pain, function and HRQoL.

RESULTS

13 studies reported 95 empirically estimated anchor-based MIDs for 8 PRO instruments and/or their subdomains that measure knee pain, function or HRQoL. All studies used a transition rating (global rating of change) as the anchor to ascertain the MID. Among PROs with more than 1 estimated MID, we found wide variation in MID values. Many studies suffered from serious methodological limitations. We identified the following most credible MIDs: Western Ontario and McMaster University Osteoarthritis Index (WOMAC; pain: 12, function: 13), Knee injury and Osteoarthritis Outcome Score (KOOS; pain: 12, activities of daily living: 8) and EuroQol five dimensions Questionnaire (EQ-5D; 0.15).

CONCLUSIONS

We were able to distinguish between more and less credible MID estimates and provide best estimates for key instruments that informed evidence presentation in the associated systematic review and judgements made by the Rapid Recommendation panel.

TRIAL REGISTRATION NUMBER

CRD42016047912.

Knee arthroscopy versus conservative management in patients with degenerative knee disease: a systematic review

OBJECTIVE

To determine the effects and complications of arthroscopic surgery compared with conservative management strategies in patients with degenerative knee disease.

DESIGN

Systematic review.

MAIN OUTCOME MEASURES

Pain, function, adverse events.

DATA SOURCES

MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), Google Scholar and Open Grey up to August 2016.

ELIGIBILITY CRITERIA

For effects, randomised clinical trials (RCTs) comparing arthroscopic surgery with a conservative management strategy (including sham surgery) in patients with degenerative knee disease. For complications, RCTs and observational studies.

REVIEW METHODS

Two reviewers independently extracted data and assessed risk of bias for patient-important outcomes. A parallel guideline committee (BMJ Rapid Recommendations) provided input on the design and interpretation of the systematic review, including selection of patient-important outcomes. We used the GRADE approach to rate the certainty (quality) of the evidence.

RESULTS

We included 13 RCTs and 12 observational studies. With respect to pain, the review identified high-certainty evidence that knee arthroscopy results in a very small reduction in pain up to 3 months (mean difference =5.4 on a 100-point scale, 95% CI 2.0 to 8.8) and very small or no pain reduction up to 2 years (mean difference =3.1, 95% CI -0.2 to 6.4) when compared with conservative management. With respect to function, the review identified moderate-certainty evidence that knee arthroscopy results in a very small improvement in the short term (mean difference =4.9 on a 100-point scale, 95% CI 1.5 to 8.4) and very small or no improved function up to 2 years (mean difference =3.2, 95% CI -0.5 to 6.8). Alternative presentations of magnitude of effect, and associated sensitivity analyses, were consistent with the findings of the primary analysis. Low-quality evidence suggested a very low probability of serious complications after knee arthroscopy.

CONCLUSIONS

Over the long term, patients who undergo knee arthroscopy versus those who receive conservative management strategies do not have important benefits in pain or function.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42016046242.

Premature Discontinuation of Pediatric Randomized Controlled Trials: A Retrospective Cohort Study

OBJECTIVES

To determine the proportion of pediatric randomized controlled trials (RCTs) that are prematurely discontinued, examine the reasons for discontinuation, and compare the risk for recruitment failure in pediatric and adult RCTs.

STUDY DESIGN

A retrospective cohort study of RCTs approved by 1 of 6 Research Ethics Committees (RECs) in Switzerland, Germany, and Canada between 2000 and 2003. We recorded trial characteristics, trial discontinuation, and reasons for discontinuation from protocols, corresponding publications, REC files, and a survey of trialists.

RESULTS

We included 894 RCTs, of which 86 enrolled children and 808 enrolled adults. Forty percent of the pediatric RCTs and 29% of the adult RCTs were discontinued. Slow recruitment accounted for 56% of pediatric RCT discontinuations and 43% of adult RCT discontinuations. Multivariable logistic regression analyses suggested that pediatric RCT was not an independent risk factor for recruitment failure after adjustment for other potential risk factors (aOR, 1.22; 95% CI, 0.57-2.63). Independent risk factors were acute care setting (aOR, 4.00; 95% CI, 1.72-9.31), nonindustry sponsorship (aOR, 4.45; 95% CI, 2.59-7.65), and smaller planned sample size (aOR, 1.05; 95% CI 1.01-1.09, in decrements of 100 participants).

CONCLUSION

Forty percent of pediatric RCTs were discontinued prematurely, owing predominately to slow recruitment. Enrollment of children was not an independent risk factor for recruitment failure.

Cerebral Embolic Protection Devices During Transcatheter Aortic Valve Implantation

Background and Purpose—

Silent ischemic embolic lesions are common after transcatheter aortic valve implantation (TAVI). The use of embolic protection devices (EPD) may reduce the occurrence of these embolic lesions. Thus, a quantitative overview and credibility assessment of the literature was necessary to draw a robust message about EPD. Therefore, the aim of this meta-analysis was to study whether the use of EPD reduces silent ischemic and clinically evident cerebrovascular events associated with TAVI.

Methods—

We conducted a comprehensive search to identify studies that evaluated patients undergoing TAVI with or without EPD. Random-effects meta-analyses were performed to estimate the effect of EPD compared with no-EPD during TAVI using aggregate data.

Results—

Sixteen studies involving 1170 patients (865/305 with/without EPD) fulfilled the inclusion criteria. The EPD delivery success rate was reported in all studies and was achieved in 94.5% of patients. Meta-analyses evaluating EPD versus without EPD strategies could not confirm or exclude any differences in terms of clinically evident stroke (relative risk, 0.70; 95% confidence interval [CI], 0.38–1.29; P =0.26) or 30-day mortality (relative risk, 0.58; 95% CI, 0.20–1.64; P =0.30). There were no significant differences in new-single, multiple, or total number of lesions. The use of EPD was associated with a significantly smaller ischemic volume per lesion (standardized mean difference, −0.52; 95% CI, −0.85 to −0.20; P =0.002) and smaller total volume of lesions (standardized mean difference, −0.23; 95% CI, −0.42 to −0.03; P =0.02). Subgroup analysis by type of valve showed an overall trend toward significant reduction in new lesions per patient using EPD (standardized mean difference, −0.41; 95% CI, −0.82 to 0.00; P =0.05), driven by self-expanding devices.

Conclusions—

The use of EPD during TAVI may be associated with smaller volume of silent ischemic lesions and smaller total volume of silent ischemic lesions. However, EPD may not reduce the number of new-single, multiple, or total number of lesions. There was only very low quality of evidence showing no significant differences between patients undergoing TAVI with or without EPD with respect to clinically evident stroke and mortality.

Low intensity pulsed ultrasound for bone healing: systematic review of randomized controlled trials

Objective To determine the efficacy of low intensity pulsed ultrasound (LIPUS) for healing of fracture or osteotomy.Design Systematic review and meta-analysis.Data sources Medline, Embase, CINAHL, Cochrane Central Register of Controlled Trials, and trial registries up to November 2016.Study selection Randomized controlled trials of LIPUS compared with sham device or no device in patients with any kind of fracture or osteotomy.Review methods Two independent reviewers identified studies, extracted data, and assessed risk of bias. A parallel guideline committee (BMJ Rapid Recommendation) provided input on the design and interpretation of the systematic review, including selection of outcomes important to patients. The GRADE system was used to assess the quality of evidence.Results 26 randomized controlled trials with a median sample size of 30 (range 8-501) were included. The most trustworthy evidence came from four trials at low risk of bias that included patients with tibia or clavicle fractures. Compared with control, LIPUS did not reduce time to return to work (percentage difference: 2.7% later with LIPUS, 95% confidence interval 7.7% earlier to 14.3% later; moderate certainty) or the number of subsequent operations (risk ratio 0.80, 95% confidence interval 0.55 to 1.16; moderate certainty). For pain, days to weight bearing, and radiographic healing, effects varied substantially among studies. For all three outcomes, trials at low risk of bias failed to show a benefit with LIPUS, while trials at high risk of bias suggested a benefit (interaction P<0.001). When only trials at low risk of bias trials were considered, LIPUS did not reduce days to weight bearing (4.8% later, 4.0% earlier to 14.4% later; high certainty), pain at four to six weeks (mean difference on 0-100 visual analogue scale: 0.93 lower, 2.51 lower to 0.64 higher; high certainty), and days to radiographic healing (1.7% earlier, 11.2% earlier to 8.8% later; moderate certainty).Conclusions Based on moderate to high quality evidence from studies in patients with fresh fracture, LIPUS does not improve outcomes important to patients and probably has no effect on radiographic bone healing. The applicability to other types of fracture or osteotomy is open to debate.Systematic review registration PROSPERO CRD42016050965.

Patient values and preferences on transcatheter or surgical aortic valve replacement therapy for aortic stenosis: a systematic review

OBJECTIVE

To investigate patients' values and preferences regarding aortic valve replacement therapy for aortic stenosis.

SETTING

Studies published after transcatheter aortic valve insertion (TAVI) became available (2002).

PARTICIPANTS

Adults with aortic stenosis who are considering or have had valve replacement, either TAVI or via surgery (surgical aortic valve replacement, SAVR).

OUTCOME MEASURES

We sought quantitative measurements, or qualitative descriptions, of values and preferences. When reported, we examined correlations between preferences and objective (eg, ejection fraction) or subjective (eg, health-related quality of life) measures of health.

RESULTS

We reviewed 1348 unique citations, of which 2 studies proved eligible. One study of patients with severe aortic stenosis used a standard gamble study to ascertain that the median hypothetical mortality risk patients were willing to tolerate to achieve full health was 25% (IQR 25-50%). However, there was considerable variability; for mortality risk levels defined by current guidelines, 130 participants (30%) were willing to accept low-to-intermediate risk (≤8%), 224 (51%) high risk (>8-50%) and 85 (19%) a risk that guidelines would consider prohibitive (>50%). Study authors did not, however, assess participants' understanding of the exercise, resulting in a potential risk of bias. A second qualitative study of 15 patients identified the following factors that influence patients to undergo assessment for TAVI: symptom burden; expectations; information support; logistical barriers; facilitators; obligations and responsibilities. The study was limited by serious risk of bias due to authors' conflict of interest (5/9 authors industry-funded).

CONCLUSIONS

Current evidence on patient values and preferences of adults with aortic stenosis is very limited, and no studies have enrolled patients deciding between TAVI and SAVR. On the basis of the data available, there is evidence of variability in individual values and preferences, highlighting the importance of well-informed and shared decision-making with patients facing this decision.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42016041907.

Prognosis after surgical replacement with a bioprosthetic aortic valve in patients with severe symptomatic aortic stenosis: systematic review of observational studies

OBJECTIVE

 To determine the frequency of survival, stroke, atrial fibrillation, structural valve deterioration, and length of hospital stay after surgical replacement of an aortic valve (SAVR) with a bioprosthetic valve in patients with severe symptomatic aortic stenosis.

DESIGN

 Systematic review and meta-analysis of observational studies.

DATA SOURCES

 Medline, Embase, PubMed (non-Medline records only), Cochrane Database of Systematic Reviews, and Cochrane CENTRAL from 2002 to June 2016.

STUDY SELECTION

 Eligible observational studies followed patients after SAVR with a bioprosthetic valve for at least two years.

METHODS

 Reviewers, independently and in duplicate, evaluated study eligibility, extracted data, and assessed risk of bias for patient important outcomes. We used the GRADE system to quantify absolute effects and quality of evidence. Published survival curves provided data for survival and freedom from structural valve deterioration, and random effect models provided the framework for estimates of pooled incidence rates of stroke, atrial fibrillation, and length of hospital stay.

RESULTS

 In patients undergoing SAVR with a bioprosthetic valve, median survival was 16 years in those aged 65 or less, 12 years in those aged 65 to 75, seven years in those aged 75 to 85, and six years in those aged more than 85. The incidence rate of stroke was 0.25 per 100 patient years (95% confidence interval 0.06 to 0.54) and atrial fibrillation 2.90 per 100 patient years (1.78 to 4.79). Post-SAVR, freedom from structural valve deterioration was 94.0% at 10 years, 81.7% at 15 years, and 52% at 20 years, and mean length of hospital stay was 12 days (95% confidence interval 9 to 15).

CONCLUSION

 Patients with severe symptomatic aortic stenosis undergoing SAVR with a bioprosthetic valve can expect only slightly lower survival than those without aortic stenosis, and a low incidence of stroke and, up to 10 years, of structural valve deterioration. The rate of deterioration increases rapidly after 10 years, and particularly after 15 years.

Authors seldom report the most patient-important outcomes and absolute effect measures in systematic review abstracts

OBJECTIVES

Explicit reporting of absolute measures is important to ensure treatment effects are correctly interpreted. We examined the extent to which authors report absolute effects for patient-important outcomes in abstracts of systematic review (SR).

STUDY DESIGN AND SETTING

We searched OVID MEDLINE and Cochrane Database of Systematic Reviews to identify eligible SRs published in the year 2010. Citations were stratified into Cochrane and non-Cochrane reviews, with repeated random sampling in a 1:1 ratio. Paired reviewers screened articles and recorded abstract characteristics, including reporting of effect measures for the most patient-important outcomes of benefit and harm.

RESULTS

We included 96 Cochrane and 94 non-Cochrane reviews. About 117 (77.5%) relative measures were reported in abstracts for outcomes of benefit, whereas only 34 (22.5%) absolute measures were reported. Similarly, for outcomes of harm, 41 (87.2%) relative measures were provided in abstracts, compared with only 6 (12.8%) absolute measures. Eighteen (9.5%) abstracts reported both absolute and relative measures for outcomes of benefit, whereas only two (1.1%) abstracts reported both measures for outcomes of harm. Results were similar between Cochrane and non-Cochrane reviews.

CONCLUSION

SR abstracts seldom report measures of absolute effect. Journal editors should insist that authors report both relative and absolute effects for patient-important outcomes.

Agreements between Industry and Academia on Publication Rights: A Retrospective Study of Protocols and Publications of Randomized Clinical Trials

BACKGROUND

Little is known about publication agreements between industry and academic investigators in trial protocols and the consistency of these agreements with corresponding statements in publications. We aimed to investigate (i) the existence and types of publication agreements in trial protocols, (ii) the completeness and consistency of the reporting of these agreements in subsequent publications, and (iii) the frequency of co-authorship by industry employees.

METHODS AND FINDINGS

We used a retrospective cohort of randomized clinical trials (RCTs) based on archived protocols approved by six research ethics committees between 13 January 2000 and 25 November 2003. Only RCTs with industry involvement were eligible. We investigated the documentation of publication agreements in RCT protocols and statements in corresponding journal publications. Of 647 eligible RCT protocols, 456 (70.5%) mentioned an agreement regarding publication of results. Of these 456, 393 (86.2%) documented an industry partner's right to disapprove or at least review proposed manuscripts; 39 (8.6%) agreements were without constraints of publication. The remaining 24 (5.3%) protocols referred to separate agreement documents not accessible to us. Of those 432 protocols with an accessible publication agreement, 268 (62.0%) trials were published. Most agreements documented in the protocol were not reported in the subsequent publication (197/268 [73.5%]). Of 71 agreements reported in publications, 52 (73.2%) were concordant with those documented in the protocol. In 14 of 37 (37.8%) publications in which statements suggested unrestricted publication rights, at least one co-author was an industry employee. In 25 protocol-publication pairs, author statements in publications suggested no constraints, but 18 corresponding protocols documented restricting agreements.

CONCLUSIONS

Publication agreements constraining academic authors' independence are common. Journal articles seldom report on publication agreements, and, if they do, statements can be discrepant with the trial protocol.

Premature Discontinuation of Randomized Trials in Critical and Emergency Care: A Retrospective Cohort Study

OBJECTIVES

Randomized clinical trials that enroll patients in critical or emergency care (acute care) setting are challenging because of narrow time windows for recruitment and the inability of many patients to provide informed consent. To assess the extent that recruitment challenges lead to randomized clinical trial discontinuation, we compared the discontinuation of acute care and nonacute care randomized clinical trials.

DESIGN

Retrospective cohort of 894 randomized clinical trials approved by six institutional review boards in Switzerland, Germany, and Canada between 2000 and 2003.

SETTING

Randomized clinical trials involving patients in an acute or nonacute care setting.

SUBJECTS AND INTERVENTIONS

We recorded trial characteristics, self-reported trial discontinuation, and self-reported reasons for discontinuation from protocols, corresponding publications, institutional review board files, and a survey of investigators.

MEASUREMENTS AND MAIN RESULTS

Of 894 randomized clinical trials, 64 (7%) were acute care randomized clinical trials (29 critical care and 35 emergency care). Compared with the 830 nonacute care randomized clinical trials, acute care randomized clinical trials were more frequently discontinued (28 of 64, 44% vs 221 of 830, 27%; p = 0.004). Slow recruitment was the most frequent reason for discontinuation, both in acute care (13 of 64, 20%) and in nonacute care randomized clinical trials (7 of 64, 11%). Logistic regression analyses suggested the acute care setting as an independent risk factor for randomized clinical trial discontinuation specifically as a result of slow recruitment (odds ratio, 4.00; 95% CI, 1.72-9.31) after adjusting for other established risk factors, including nonindustry sponsorship and small sample size.

CONCLUSIONS

Acute care randomized clinical trials are more vulnerable to premature discontinuation than nonacute care randomized clinical trials and have an approximately four-fold higher risk of discontinuation due to slow recruitment. These results highlight the need for strategies to reliably prevent and resolve slow patient recruitment in randomized clinical trials conducted in the critical and emergency care setting.

Meta-analysis of antibiotics versus appendicectomy for non-perforated acute appendicitis

Background

For more than a century, appendicectomy has been the treatment of choice for appendicitis. Recent trials have challenged this view. This study assessed the benefits and harms of antibiotic therapy compared with appendicectomy in patients with non‐perforated appendicitis.

Methods

A comprehensive search was conducted for randomized trials comparing antibiotic therapy with appendicectomy in patients with non‐perforated appendicitis. Key outcomes were analysed using random‐effects meta‐analysis, and the quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

Results

Five studies including 1116 patients reported major complications in 25 (4·9 per cent) of 510 patients in the antibiotic and 41 (8·4 per cent) of 489 in the appendicectomy group: risk difference −2·6 (95 per cent c.i. –6·3 to 1·1) per cent (low‐quality evidence). Minor complications occurred in 11 (2·2 per cent) of 510 and 61 (12·5 per cent) of 489 patients respectively: risk difference −7·2 (−18·1 to 3·8) per cent (very low‐quality evidence). Of 550 patients in the antibiotic group, 47 underwent appendicectomy within 1 month: pooled estimate 8·2 (95 per cent c.i. 5·2 to 11·8) per cent (high‐quality evidence). Within 1 year, appendicitis recurred in 114 of 510 patients in the antibiotic group: pooled estimate 22·6 (15·6 to 30·4) per cent (high‐quality evidence). For every 100 patients with non‐perforated appendicitis, initial antibiotic therapy compared with prompt appendicectomy may result in 92 fewer patients receiving surgery within the first month, and 23 more experiencing recurrent appendicitis within the first year.

Conclusion

The choice of medical versus surgical management in patients with clearly uncomplicated appendicitis is value‐ and preference‐dependent, suggesting a change in practice towards shared decision‐making is necessary.

Limitations of each evolving

Do clinicians understand the size of treatment effects? A randomized survey across 8 countries

BACKGROUND

Meta-analyses of continuous outcomes typically provide enough information for decision-makers to evaluate the extent to which chance can explain apparent differences between interventions. The interpretation of the magnitude of these differences - from trivial to large - can, however, be challenging. We investigated clinicians' understanding and perceptions of usefulness of 6 statistical formats for presenting continuous outcomes from meta-analyses (standardized mean difference, minimal important difference units, mean difference in natural units, ratio of means, relative risk and risk difference).

METHODS

We invited 610 staff and trainees in internal medicine and family medicine programs in 8 countries to participate. Paper-based, self-administered questionnaires presented summary estimates of hypothetical interventions versus placebo for chronic pain. The estimates showed either a small or a large effect for each of the 6 statistical formats for presenting continuous outcomes. Questions addressed participants' understanding of the magnitude of treatment effects and their perception of the usefulness of the presentation format. We randomly assigned participants 1 of 4 versions of the questionnaire, each with a different effect size (large or small) and presentation order for the 6 formats (1 to 6, or 6 to 1).

RESULTS

Overall, 531 (87.0%) of the clinicians responded. Respondents best understood risk difference, followed by relative risk and ratio of means. Similarly, they perceived the dichotomous presentation of continuous outcomes (relative risk and risk difference) to be most useful. Presenting results as a standardized mean difference, the longest standing and most widely used approach, was poorly understood and perceived as least useful.

INTERPRETATION

None of the presentation formats were well understood or perceived as extremely useful. Clinicians best understood the dichotomous presentations of continuous outcomes and perceived them to be the most useful. Further initiatives to help clinicians better grasp the magnitude of the treatment effect are needed.

Corticosteroid Therapy for Patients Hospitalized With Community-Acquired Pneumonia: A Systematic Review and Meta-analysis

BACKGROUND

Community-acquired pneumonia (CAP) is common and often severe.

PURPOSE

To examine the effect of adjunctive corticosteroid therapy on mortality, morbidity, and duration of hospitalization in patients with CAP.

DATA SOURCES

MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials through 24 May 2015.

STUDY SELECTION

Randomized trials of systemic corticosteroids in hospitalized adults with CAP.

DATA EXTRACTION

Two reviewers independently extracted study data and assessed risk of bias. Quality of evidence was assessed with the Grading of Recommendations Assessment, Development, and Evaluation system by consensus among the authors.

DATA SYNTHESIS

The median age was typically in the 60s, and approximately 60% of patients were male. Adjunctive corticosteroids were associated with possible reductions in all-cause mortality (12 trials; 1974 patients; risk ratio [RR], 0.67 [95% CI, 0.45 to 1.01]; risk difference [RD], 2.8%; moderate certainty), need for mechanical ventilation (5 trials; 1060 patients; RR, 0.45 [CI, 0.26 to 0.79]; RD, 5.0%; moderate certainty), and the acute respiratory distress syndrome (4 trials; 945 patients; RR, 0.24 [CI, 0.10 to 0.56]; RD, 6.2%; moderate certainty). They also decreased time to clinical stability (5 trials; 1180 patients; mean difference, -1.22 days [CI, -2.08 to -0.35 days]; high certainty) and duration of hospitalization (6 trials; 1499 patients; mean difference, -1.00 day [CI, -1.79 to -0.21 days]; high certainty). Adjunctive corticosteroids increased frequency of hyperglycemia requiring treatment (6 trials; 1534 patients; RR, 1.49 [CI, 1.01 to 2.19]; RD, 3.5%; high certainty) but did not increase frequency of gastrointestinal hemorrhage.

LIMITATIONS

There were few events and trials for many outcomes. Trials often excluded patients at high risk for adverse events.

CONCLUSION

For hospitalized adults with CAP, systemic corticosteroid therapy may reduce mortality by approximately 3%, need for mechanical ventilation by approximately 5%, and hospital stay by approximately 1 day.

PRIMARY FUNDING SOURCE

None.

Reporting, handling and assessing the risk of bias associated with missing participant data in systematic reviews: a methodological survey

OBJECTIVES

To describe how systematic reviewers are reporting missing data for dichotomous outcomes, handling them in the analysis and assessing the risk of associated bias.

METHODS

We searched MEDLINE and the Cochrane Database of Systematic Reviews for systematic reviews of randomised trials published in 2010, and reporting a meta-analysis of a dichotomous outcome. We randomly selected 98 Cochrane and 104 non-Cochrane systematic reviews. Teams of 2 reviewers selected eligible studies and abstracted data independently and in duplicate using standardised, piloted forms with accompanying instructions. We conducted regression analyses to explore factors associated with using complete case analysis and with judging the risk of bias associated with missing participant data.

RESULTS

Of Cochrane and non-Cochrane reviews, 47% and 7% (p<0.0001), respectively, reported on the number of participants with missing data, and 41% and 9% reported a plan for handling missing categorical data. The 2 most reported approaches for handling missing data were complete case analysis (8.5%, out of the 202 reviews) and assuming no participants with missing data had the event (4%). The use of complete case analysis was associated only with Cochrane reviews (relative to non-Cochrane: OR=7.25; 95% CI 1.58 to 33.3, p=0.01). 65% of reviews assessed risk of bias associated with missing data; this was associated with Cochrane reviews (relative to non-Cochrane: OR=6.63; 95% CI 2.50 to 17.57, p=0.0001), and the use of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology (OR=5.02; 95% CI 1.02 to 24.75, p=0.047).

CONCLUSIONS

Though Cochrane reviews are somewhat less problematic, most Cochrane and non-Cochrane systematic reviews fail to adequately report and handle missing data, potentially resulting in misleading judgements regarding risk of bias.

Longer- Versus Shorter-Duration Dual-Antiplatelet Therapy After Drug-Eluting Stent Placement: A Systematic Review and Meta-analysis

BACKGROUND

The appropriate duration of dual-antiplatelet therapy (DAPT) after drug-eluting stent (DES) placement remains controversial.

PURPOSE

To summarize data on clinical outcomes with longer- versus shorter-duration DAPT after DES placement in adults with coronary artery disease.

DATA SOURCES

Ovid MEDLINE and EMBASE, 1996 to 27 March 2015, and manual screening of references.

STUDY SELECTION

Randomized, controlled trials comparing longer- versus shorter-duration DAPT after DES placement.

DATA EXTRACTION

Two reviewers screened potentially eligible articles; extracted data on populations, interventions, and outcomes; assessed risk of bias; and used the Grading of Recommendations Assessment, Development and Evaluation guidelines to rate overall confidence in effect estimates.

DATA SYNTHESIS

Among 1010 articles identified, 9 trials including 29,531 patients were eligible; data were complete for 28,808 patients. Moderate-quality evidence showed that longer-duration DAPT decreased risk for myocardial infarction (risk ratio [RR], 0.73 [95% CI, 0.58 to 0.92]) and increased mortality (RR, 1.19 [CI, 1.04 to 1.36]). High-quality evidence showed that DAPT increased risk for major bleeding (RR, 1.63 [CI, 1.34 to 1.99]).

LIMITATION

Confidence in estimates were decreased owing to imprecision for most outcomes (particularly myocardial infarction), risk of bias from limited blinding in 7 of 9 studies, indirectness due to variability in use of first- and second-generation stents, and off-protocol use of DAPT in some studies.

CONCLUSION

Extended DAPT is associated with approximately 8 fewer myocardial infarctions per 1000 treated patients per year but 6 more major bleeding events than shorter-duration DAPT. Because absolute effects are very small and closely balanced, decisions regarding the duration of DAPT therapy must take into account patients' values and preference.

PRIMARY FUNDING SOURCE

None.

Subgroup analyses in randomised controlled trials: cohort study on trial protocols and journal publications

OBJECTIVE

To investigate the planning of subgroup analyses in protocols of randomised controlled trials and the agreement with corresponding full journal publications.

DESIGN

Cohort of protocols of randomised controlled trial and subsequent full journal publications.

SETTING

Six research ethics committees in Switzerland, Germany, and Canada.

DATA SOURCES

894 protocols of randomised controlled trial involving patients approved by participating research ethics committees between 2000 and 2003 and 515 subsequent full journal publications.

RESULTS

Of 894 protocols of randomised controlled trials, 252 (28.2%) included one or more planned subgroup analyses. Of those, 17 (6.7%) provided a clear hypothesis for at least one subgroup analysis, 10 (4.0%) anticipated the direction of a subgroup effect, and 87 (34.5%) planned a statistical test for interaction. Industry sponsored trials more often planned subgroup analyses compared with investigator sponsored trials (195/551 (35.4%) v 57/343 (16.6%), P<0.001). Of 515 identified journal publications, 246 (47.8%) reported at least one subgroup analysis. In 81 (32.9%) of the 246 publications reporting subgroup analyses, authors stated that subgroup analyses were prespecified, but this was not supported by 28 (34.6%) corresponding protocols. In 86 publications, authors claimed a subgroup effect, but only 36 (41.9%) corresponding protocols reported a planned subgroup analysis.

CONCLUSIONS

Subgroup analyses are insufficiently described in the protocols of randomised controlled trials submitted to research ethics committees, and investigators rarely specify the anticipated direction of subgroup effects. More than one third of statements in publications of randomised controlled trials about subgroup prespecification had no documentation in the corresponding protocols. Definitive judgments regarding credibility of claimed subgroup effects are not possible without access to protocols and analysis plans of randomised controlled trials.

Prevalence, characteristics, and publication of discontinued randomized trials

IMPORTANCE

The discontinuation of randomized clinical trials (RCTs) raises ethical concerns and often wastes scarce research resources. The epidemiology of discontinued RCTs, however, remains unclear.

OBJECTIVES

To determine the prevalence, characteristics, and publication history of discontinued RCTs and to investigate factors associated with RCT discontinuation due to poor recruitment and with nonpublication.

DESIGN AND SETTING

Retrospective cohort of RCTs based on archived protocols approved by 6 research ethics committees in Switzerland, Germany, and Canada between 2000 and 2003. We recorded trial characteristics and planned recruitment from included protocols. Last follow-up of RCTs was April 27, 2013.

MAIN OUTCOMES AND MEASURES

Completion status, reported reasons for discontinuation, and publication status of RCTs as determined by correspondence with the research ethics committees, literature searches, and investigator surveys.

RESULTS

After a median follow-up of 11.6 years (range, 8.8-12.6 years), 253 of 1017 included RCTs were discontinued (24.9% [95% CI, 22.3%-27.6%]). Only 96 of 253 discontinuations (37.9% [95% CI, 32.0%-44.3%]) were reported to ethics committees. The most frequent reason for discontinuation was poor recruitment (101/1017; 9.9% [95% CI, 8.2%-12.0%]). In multivariable analysis, industry sponsorship vs investigator sponsorship (8.4% vs 26.5%; odds ratio [OR], 0.25 [95% CI, 0.15-0.43]; P < .001) and a larger planned sample size in increments of 100 (-0.7%; OR, 0.96 [95% CI, 0.92-1.00]; P = .04) were associated with lower rates of discontinuation due to poor recruitment. Discontinued trials were more likely to remain unpublished than completed trials (55.1% vs 33.6%; OR, 3.19 [95% CI, 2.29-4.43]; P < .001).

CONCLUSIONS AND RELEVANCE

In this sample of trials based on RCT protocols from 6 research ethics committees, discontinuation was common, with poor recruitment being the most frequently reported reason. Greater efforts are needed to ensure the reporting of trial discontinuation to research ethics committees and the publication of results of discontinued trials.