Published methodological quality of randomized controlled trials does not reflect the actual quality assessed in protocols

The effect of compression therapies and therapeutic modalities on lymphedema secondary to cancer: a rapid review and evidence map

The identification of effective therapeutic modalities to manage lymphedema secondary to cancer is a high priority among patients and clinicians. Complex decongestive therapy (CDT) remains a fundamental intervention for individuals with lymphedema; however, interventions involving modalities such as low level laser therapy, specially designed compression systems, and compression pumps may be helpful to improve outcomes and reduce costs of care. We conducted a rapid review of the literature examining compression therapies and therapeutic modalities in the treatment of lymphedema secondary to cancer. A search of the electronic databases from June 2018 to October 2023 was performed including MEDLINE, EMBASE, and CINAHL. The electronic search yielded 438 potentially relevant citations with 40 randomized controlled trials included in the review, and 30 in the mapping process. Ninety-three percent (n = 37) of the trials included participants with a diagnosis of breast cancer. Across all categories and domains, all but two trials were rated as having 'some concerns' or a 'high risk of bias'. Intervention effects ranged from clinically insignificant to large effects on lymphedema volume. Evidence mapping suggests potential for benefit from (1) compression garments for the prevention of lymphedema, (2) interventions added to CDT in the intensive reduction phase, and (3) nighttime compression and compression pump treatments in the maintenance phase. A multi-centre collaborative research approach is needed to support the conduct of high-quality large-scale trials to inform the optimal type, timing, and combination of compression therapies and therapeutic modalities in the treatment of lymphedema secondary to cancer.

Does renal denervation require cardiovascular outcome-driven data?

Hypertension is a major driver of cardiovascular disease with a prevalence of 32-34% in adults worldwide. This poses a formidable unmet challenge for healthcare systems, highlighting the need for enhanced treatment strategies. Since 2017, eight major sham-controlled randomised controlled trials have examined the effectiveness and safety of renal denervation (RDN) as therapy for BP control. Although most trials demonstrated a reduction in systolic 24-hour/daytime ambulatory BP compared to control groups, open to discussion is whether major adverse cardiovascular events (MACE)-driven RDN trials are necessary or whether the proof of BP reduction as a surrogate for better cardiovascular outcomes is sufficient. We conducted an analysis of the statistical methods used in various trials to assess endpoint definitions and determine the necessity for MACE-driven outcome data. Such comprehensive analysis provides further evidence to confidently conclude that RDN significantly reduces blood pressure compared to sham controls. Importantly, this enables the interpolation of RDN trial endpoints with other studies that report on outcome data, such as pharmacological trials which demonstrate a significant reduction in MACE risk with a decrease in BP. Moreover, limitations associated with directly evaluating outcome data further support the use of BP as a surrogate endpoint. For example, conducting lengthier trials with larger numbers of participants to ensure robust statistical power presents a substantial challenge to evaluating outcome data. Thus, in light of the crucial need to tackle hypertension, there are notable advantages of considering BP as a surrogate for outcome data.

Screw loosening in angulation-correcting single implant restorations: A systematic review of in vitro studies

STATEMENT OF PROBLEM

Various options are available to allow angle correction for screw-retained restorations for malaligned implants, including angled abutments, angled screw channel abutments, and angled implants. However, the effect these angle correction components have on prosthetic screw loosening is unclear.

PURPOSE

The purpose of this systematic review was to assess the effect of angled abutments, angled screw channel abutments, and angled implants on prosthetic screw loosening.

MATERIAL AND METHODS

This manuscript followed the Preferred Reporting Items for the Systematic Review and Meta-Analyses (PRISMA) statement. Searches were performed through 31 December 2021 in PubMed/MEDLINE, EMBASE, and Web of Science with no year limit targeting in vitro studies evaluating the effect of angulation correction components on screw loosening.

RESULTS

A total of 460 articles were identified. After removing duplicates, 306 titles were screened. Nine of the remaining 36 articles selected for full-text analysis met the selection criteria. The qualitative analysis used data from 394 implants. All studies featured straight abutments as the control group, and, in 8 studies, the angle correction component was included on the level of the abutment. Only in 1 study was the angle correction component at the level of the implant. The angle correction of the prosthetic component varied from 0 degrees in all studies up to a maximum correction of 30 degrees. Statistically significant increases in screw loosening with increasing abutment angle correction were reported by multiple authors (P<.05). However, other articles reported nonsignificant differences in screw loosening because of angulation after cyclic loading (P>.05). The only study investigating angle correction at the implant level found significantly less screw loosening (P<.05) in the angled implant group compared with the nonangled implant group.

CONCLUSIONS

Several options are available to correct discrepancies between the surgical axis and the ideal prosthetic axis for rehabilitations supported by dental implants. The current evidence does not clearly indicate the superiority of any single solution for minimizing screw loosening.

Evaluation of quality and quantity of randomized controlled trials in hepatobiliary surgery: A scoping/mapping review

AIM

To evaluate the quantity and quality of randomized controlled trials (RCTs) in hepatobiliary surgery and for identifying gaps in current evidences.

METHODS

A systematic search was conducted in MEDLINE (via PubMed), Web of Science, and Cochrane Controlled Register of Trials (CENTRAL) for RCTs of hepatobiliary surgery published from inception until the end of 2023. The quality of each study was assessed using the Cochrane risk-of-bias (RoB) tool. The associations between risk of bias and the region and publication date were also assessed. Evidence mapping was performed to identify research gaps in the field.

RESULTS

The study included 1187 records. The number and proportion of published randomized controlled trials (RCTs) in hepatobiliary surgery increased over time, from 13 RCTs (.0005% of publications) in 1970-1979 to 201 RCTs (.003% of publications) in 2020-2023. There was a significant increase in the number of studies with a low risk of bias in RoB domains (p < .01). The proportion of RCTs with low risk of bias improved significantly after the introduction of CONSORT guidelines (p < .001). The evidence mapping revealed a significant research focus on major and minor hepatectomy and cholecystectomy. However, gaps were identified in liver cyst surgery and hepatobiliary vascular surgery. Additionally, there are gaps in the field of perioperative management and nutrition intervention.

CONCLUSION

The quantity and quality of RCTs in hepatobiliary surgery have increased over time, but there is still room for improvement. We have identified gaps in current research that can be addressed in future studies.

Risk of bias in exercise science: A systematic review of 340 studies

Risk of bias can contribute to irreproducible science and mislead decision making. Analyses of smaller subsections of the exercise science literature suggest many exercise science studies have unclear or high risk of bias. The current review (osf.io/jznv8) assesses whether this unclear or high risk of bias is more widespread in the exercise science literature and whether this bias has decreased since the publication of the 1996 Consolidated Standards of Reporting Trials (CONSORT) guidelines. We report significant reductions in selection, performance, detection, and reporting biases in 2020 compared with 1995 in the 340 of 5,451 studies assessed using the Cochrane Risk of Bias tool. Despite these improvements, most 2020 studies still had unclear or high risks of bias. These results underscore the need for methodological vigilance, adherence to reporting standards, and education on experimental bias. Factors contributing to these improvements, such advancements in education and journal requirements, remain uncertain.

Estimating the prevalence of discrepancies between study registrations and publications: a systematic review and meta-analyses

OBJECTIVES

Prospectively registering study plans in a permanent time-stamped and publicly accessible document is becoming more common across disciplines and aims to reduce risk of bias and make risk of bias transparent. Selective reporting persists, however, when researchers deviate from their registered plans without disclosure. This systematic review aimed to estimate the prevalence of undisclosed discrepancies between prospectively registered study plans and their associated publication. We further aimed to identify the research disciplines where these discrepancies have been observed, whether interventions to reduce discrepancies have been conducted, and gaps in the literature.

DESIGN

Systematic review and meta-analyses.

DATA SOURCES

Scopus and Web of Knowledge, published up to 15 December 2019.

ELIGIBILITY CRITERIA

Articles that included quantitative data about discrepancies between registrations or study protocols and their associated publications.

DATA EXTRACTION AND SYNTHESIS

Each included article was independently coded by two reviewers using a coding form designed for this review (osf.io/728ys). We used random-effects meta-analyses to synthesise the results.

RESULTS

We reviewed k=89 articles, which included k=70 that reported on primary outcome discrepancies from n=6314 studies and, k=22 that reported on secondary outcome discrepancies from n=1436 studies. Meta-analyses indicated that between 29% and 37% (95% CI) of studies contained at least one primary outcome discrepancy and between 50% and 75% (95% CI) contained at least one secondary outcome discrepancy. Almost all articles assessed clinical literature, and there was considerable heterogeneity. We identified only one article that attempted to correct discrepancies.

CONCLUSIONS

Many articles did not include information on whether discrepancies were disclosed, which version of a registration they compared publications to and whether the registration was prospective. Thus, our estimates represent discrepancies broadly, rather than our target of undisclosed discrepancies between prospectively registered study plans and their associated publications. Discrepancies are common and reduce the trustworthiness of medical research. Interventions to reduce discrepancies could prove valuable.

REGISTRATION

osf.io/ktmdg. Protocol amendments are listed in online supplemental material A.

A methodological framework allows the identification of personomic markers to consider when designing personalized interventions

OBJECTIVES

To develop a methodological framework to identify and prioritize personomic markers (e.g., psychosocial situation, beliefs…) to consider for personalizing interventions and to test in smoking cessation interventions.

STUDY DESIGN AND SETTING

(1) We identified potential personomic markers considered in protocols of personalized interventions, in reviews of predictors of smoking cessation, and in interviews with general practitioners. (2) Physicians, and patient smokers or former smokers selected the markers they considered most relevant during online paired comparison experiments. Data were analyzed with Bradley Terry Luce models.

RESULTS

Thirty-six personomic markers were identified from research evidence. They were evaluated by 795 physicians (median age: 34, IQR [30-38]; 95% general practitioners) and 793 patients (median age: 54, IQR [42-64], 71.4% former smokers) during 11,963 paired comparisons. Physicians identified patients' motivation for quitting (e.g., Prochaska stages), patients' preferences, and patients' fears and beliefs (e.g., concerns about weight gain) as the most relevant elements to personalize smoking cessation. Patients considered their motivation for quitting, smoking behavior (e.g., smoking at home/at work), and tobacco dependence (e.g., Fagerström Test) as the most relevant elements to consider.

CONCLUSION

We provide a methodological framework to prioritize which personomic markers should be considered when developing smoking cessation interventions.

Reporting quality was suboptimal in a systematic review of randomized controlled trials with adaptive designs

OBJECTIVE

The study was conducted to evaluate the reporting quality of randomized controlled trials (RCTs) that use an adaptive design (AD) based on the 2020 AD Consolidated Standards for Reporting Trials 2010 extension (ACE) guidelines and identify factors associated with better reporting quality.

STUDY DESIGN AND SETTING

PubMed, Embase, Cochrane, Web of Science, and Google Scholar were searched until November 1, 2022. Multivariable linear regression analysis was performed to investigate potential predictors.

RESULTS

In total, 109 RCTs were included in our study. The mean compliance rate for the ACE checklist items was 69.75% ± 16.02. Key methodological items including allocation concealment and its implementations were poorly reported. There was also suboptimal reporting of checklist items related to the conduct of interim analyzes. Multivariable regression analysis showed better reporting quality with trial registration, nonindustry affiliation (first author), a sample size of >100, general medical journal type, publication date (≥2020), funding, and disclosure of the number of interim analyzes.

CONCLUSION

Our study showed that RCTs with AD had suboptimal reporting of 2020 ACE checklist items, particularly AD-specific items. Following the development of ACE guidelines, stricter adherence to the ACE guideline is necessary to improve their reporting quality. Pre-ACE and post-ACE adherence comparisons can be conducted in the future.

The reporting quality of N-of-1 trials and protocols still needs improvement

OBJECTIVE

To evaluate the reporting quality of single-patient (N-of-1) trials and protocols based on the CONSORT Extension for N-of-1 trials (CENT) statement and the standard protocol items: recommendations for interventional trials (SPIRIT) extension and elaboration for N-of-1 trials (SPENT) checklist to examine the factors that influenced reporting quality.

METHODS

Four electronic databases were searched to identify N-of-1 trials and protocols from 2015 to 2020. Quality was assessed by two reviewers. We calculated the overall scores based on binary responses in which "Yes" was scored as 1 (if the item was fully reported), and "No" was scored as 0 (if the item was not clearly reported or not definitely stated).

RESULTS

A total of 78 publications (55 N-of-1 trials and 23 protocols) were identified. The mean reporting score (SD) of the N-of-1 trials and protocols were 29.24 (0.89) and 29.61 (1.83), respectively. For the items related to outcomes, sample size, allocation concealment protocol, and informed consent materials, the reporting quality was low. Our results showed that the year of publication (t = -0.793, p = 0.872 for the trials and t = 1.352, p = 0.623 for the protocols) and the impact factor of the journal (t = 1.416, p = 0.619 for the trials and t = 0.359, p = 0.667 for the protocols) were not factors associated with better reporting quality.

CONCLUSION

With the publication of the CENT 2015 statement and the SPENT 2019 checklist, authors should adhere to the relevant reporting guidelines and improve the reporting quality of N-of-1 trials and protocols.

Risk of Bias in Iranian Randomized Trials Included in Cochrane Reviews

BACKGROUND

Among interventional studies, randomized controlled trials (RCTs) provide the highest level of evidence. However, RCTs can be susceptible to the risk of bias (RoB). Systematic reviews can be performed to appraise RoB in the included articles using evaluative tools. This study aimed to describe the main characteristics and focus on the RoB of RCTs conducted in Iran and included in Cochrane Reviews (CRs).

METHODS

We searched "Iran" by selecting the "Search All Text" and "Review" fields in the Cochrane Database of Systematic Reviews within Ovid. CRs that included the RCTs conducted in Iran were retrieved. A trial was selected only if it was included in CRs, described as a controlled clinical trial, involved human subjects and CR authors assessed its RoB. The trials were characterized by investigating the relevant articles and the table "Characteristics of included studies" in each CR. The RoB was investigated by collecting the review authors' judgments based on RoB assessment tables in the CRs.

RESULTS

Out of 1166 Iranian RCTs included by 571 CRs, low RoB was found in 44.9% for random sequence generation, 20.8% for allocation concealment, 32.3% for blinding of participants/personnel, 36.5% for blinding of outcome assessors, 56.3% for incomplete outcome data, 41.3% for selective outcome reporting and 53.8% for other sources of bias.

CONCLUSION

The RoB in Iranian RCTs was found to be mostly high or unclear. While this is similar to the global situation, it is recommended that the methodological quality of conducting and reporting RCTs be addressed in Iran.

High quality (certainty) evidence changes less often than low-quality evidence, but the magnitude of effect size does not systematically differ between studies with low versus high-quality evidence

RATIONALE, AIMS, AND OBJECTIVES

It is generally believed that evidence from low quality of evidence generate inaccurate estimates about treatment effects more often than evidence from high (certainty) quality evidence (CoE). As a result, we would expect that (a) estimates of effects of health interventions initially based on high CoE change less frequently than the effects estimated by lower CoE (b) the estimates of magnitude of effect size differ between high and low CoE. Empirical assessment of these foundational principles of evidence-based medicine has been lacking.

METHODS

We reviewed the Cochrane Database of Systematic Reviews from January 2016 through May 2021 for pairs of original and updated reviews for change in CoE assessments based on the Grading of Recommendations Assessment, Development and Evaluation (GRADE) method. We assessed the difference in effect sizes between the original versus updated reviews as a function of change in CoE, which we report as a ratio of odds ratio (ROR). We compared ROR generated in the studies in which CoE changed from very low/low (VL/L) to moderate/high (M/H) versus M/H to VL/L. Heterogeneity and inconsistency were assessed using the tau and I² statistic. We also assessed the change in precision of effect estimates (by calculating the ratio of standard errors) (seR), and the absolute deviation in estimates of treatment effects (aROR).

RESULTS

Four hundred and nineteen pairs of reviews were included of which 414 (207 × 2) informed the CoE appraisal and 384 (192 × 2) the assessment of effect size. We found that CoE originally appraised as VL/L had 2.1 [95% confidence interval (CI): 1.19-4.12; p = 0.0091] times higher odds to be changed in the future studies than M/H CoE. However, the effect size was not different (p = 1) when CoE changed from VL/L → M/H [ROR = 1.02 (95% CI: 0.74-1.39)] compared with M/H → VL/L (ROR = 1.02 [95% CI: 0.44-2.37]). Similar overlap in aROR between the VL/L → M/H versus M/H → VL/L subgroups was observed [median (IQR): 1.12 (1.07-1.57) vs. 1.21 (1.12-2.43)]. We observed large inconsistency across ROR estimates (I²  = 99%). There was larger imprecision in treatment effects when CoE changed from VL/L → M/H (seR = 1.46) than when it changed from M/H → VL/L (seR = 0.72).

CONCLUSIONS

We found that low-quality evidence changes more often than high CoE. However, the effect size did not systematically differ between the studies with low versus high CoE. The finding that the effect size did not differ between low and high CoE indicate urgent need to refine current EBM critical appraisal methods.

Subgroup Analysis in Pulmonary Hypertension-Specific Therapy Clinical Trials: A Systematic Review

Pulmonary hypertension (PH) treatment decisions are driven by the results of randomized controlled trials (RCTs). Subgroup analyses are often performed to assess whether the intervention effect will change due to the patient's characteristics, thus allowing for individualized decisions. This review aimed to evaluate the appropriateness and interpretation of subgroup analyses performed in PH-specific therapy RCTs published between 2000 and 2020. Claims of subgroup effects were evaluated with prespecified criteria. Overall, 30 RCTs were included. Subgroup analyses presented: a high number of subgroup analyses reported, lack of prespecification, and lack of interaction tests. The trial protocol was not available for most RCTs; significant differences were found in those articles that published the protocol. Authors reported 13 claims of subgroup effect, with 12 claims meeting four or fewer of Sun's criteria. Even when most RCTs were generally at low risk of bias and were published in high-impact journals, the credibility and general quality of subgroup analyses and subgroup claims were low due to methodological flaws. Clinicians should be skeptical of claims of subgroup effects and interpret subgroup analyses with caution, as due to their poor quality, these analyses may not serve as guidance for personalized care.

Pharmacological and dietary-supplement treatments for autism spectrum disorder: a systematic review and network meta-analysis

BACKGROUND

There is still no approved medication for the core symptoms of autism spectrum disorder (ASD). This network meta-analysis investigated pharmacological and dietary-supplement treatments for ASD.

METHODS

We searched for randomized-controlled-trials (RCTs) with a minimum duration of seven days in ClinicalTrials.gov, EMBASE, MEDLINE, PsycINFO, WHO-ICTRP (from inception up to July 8, 2018), CENTRAL and PubMed (up to November 3, 2021). The co-primary outcomes were core symptoms (social-communication difficulties-SCD, repetitive behaviors-RB, overall core symptoms-OCS) measured by validated scales and standardized-mean-differences (SMDs). Associated symptoms, e.g., irritability/aggression and attention-deficit/hyperactivity disorder (ADHD) symptoms, dropouts and important side-effects, were investigated as secondary outcomes. Studies in children/adolescents and adults were analyzed separately in random-effects pairwise and network meta-analyses.

RESULTS

We analyzed data for 41 drugs and 17 dietary-supplements, from 125 RCTs (n = 7450 participants) in children/adolescents and 18 RCTs (n = 1104) in adults. The following medications could improve at least one core symptom domain in comparison with placebo: aripiprazole (k = 6 studies in analysis, SCD: SMD = 0.27 95% CI [0.09, 0.44], RB: 0.48 [0.26, 0.70]), atomoxetine (k = 3, RB:0.49 [0.18, 0.80]), bumetanide (k = 4, RB: 0.35 [0.09, 0.62], OCS: 0.61 [0.31, 0.91]), and risperidone (k = 4, SCM: 0.31 [0.06, 0.55], RB: 0.60 [0.29, 0.90]; k = 3, OCS: 1.18 [0.75, 1.61]) in children/adolescents; fluoxetine (k = 1, RB: 1.20 [0.45, 1.96]), fluvoxamine (k = 1, RB: 1.04 [0.27, 1.81]), oxytocin (k = 6, RB:0.41 [0.16, 0.66]) and risperidone (k = 1, RB: 0.97 [0.21,1.74]) in adults. There were some indications of improvement by carnosine, haloperidol, folinic acid, guanfacine, omega-3-fatty-acids, probiotics, sulforaphane, tideglusib and valproate, yet imprecise and not robust. Confidence in these estimates was very low or low, except moderate for oxytocin. Medications differed substantially in improving associated symptoms, and in their side-effect profiles.

LIMITATIONS

Most of the studies were inadequately powered (sample sizes of 20-80 participants), with short duration (8-13 weeks), and about a third focused on associated symptoms. Networks were mainly star-shaped, and there were indications of reporting bias. There was no optimal rating scale measuring change in core symptoms.

CONCLUSIONS

Some medications could improve core symptoms, although this could be likely secondary to the improvement of associated symptoms. Evidence on their efficacy and safety is preliminary; therefore, routine prescription of medications for the core symptoms cannot be recommended. Trial registration PROSPERO-ID CRD42019125317.

Spin in the Scientific Literature on Bariatric Endoscopy: a Systematic Review of Randomized Controlled Trials

Bariatric endoscopy (BE) is an emerging treatment option for people with obesity. Spin (i.e., the practice of frequent misrepresentation or overinterpretation of study findings) may lead to imbalanced and unjustified optimism in the interpretation of the results. The aim of this systematic review was to determine the frequency and type of spin in randomized controlled trials (RCTs) of endoscopic primary weight loss techniques with statistically significant and nonsignificant primary outcomes. In conclusion, spin is observed in the abstract and main text of BE reports and can lead to misinterpretation or overinterpretation of the results. Since BE challenges the available non-endoscopic treatments for obesity, further research is needed to better qualify these techniques, as being effective and safe, as well as predefined hypotheses and analyses.

Effect of milling, fitting adjustments, and hydrofluoric acid etching on the strength and roughness of CAD-CAM glass-ceramics: A systematic review and meta-analysis

STATEMENT OF PROBLEM

Whether procedures performed before the cementation of computer-aided design and computer-aided manufacturing (CAD-CAM) glass-ceramic restorations, including milling, fitting adjustment, and hydrofluoric acid etching introduce defects on the ceramic surface that affect the mechanical and surface properties is unclear.

PURPOSE

A systematic review and meta-analysis were conducted to assess the effect of milling, fitting adjustments, and hydrofluoric acid etching (HF) on the flexural strength and roughness (Ra) of CAD-CAM glass-ceramics.

MATERIAL AND METHODS

Literature searches were performed up to June 2020 in the PubMed/MEDLINE, Web of Science, and Scopus databases, with no publication year or language limits. The focused question was "Do milling, fitting adjustments, and hydrofluoric acid etching affect the flexural strength and roughness of CAD-CAM glass-ceramics?" For the meta-analysis, flexural strength and Ra data on milling, fitting adjustment, and HF etching versus control (polishing) were analyzed globally. A subgroup analysis assessed the effect of etching parameters (HF concentration and time) on the flexural strength and roughness of CAD-CAM glass-ceramics with different microstructures. Comparisons were performed with random-effect models at 5% significance.

RESULTS

Fourteen studies from 2764 potentially relevant records were included in the qualitative syntheses, and 12 in the meta-analysis. Milling and fitting adjustments increased roughness and reduced the flexural strength of CAD-CAM glass-ceramics. The effect of HF etching was dependent on the glass-ceramic microstructure, HF concentration, and etching time. For feldspathic- and leucite-reinforced ceramics, HF 5% applied for between 30 and 120 seconds increased roughness without affecting flexural strength. For lithium disilicate glass-ceramics, HF concentrations greater than 4.9% used for 20 seconds or more reduced the strength without affecting the surface roughness.

CONCLUSIONS

The flexural strength of CAD-CAM glass-ceramic is reduced by grinding procedures such as milling and fitting adjustment. Ceramic microstructure, HF concentration, and etching time determined the effect of hydrofluoric acid etching on the flexural strength and surface roughness of glass-ceramic materials.

Assessing the uncertainty of treatment outcomes in a previous systematic review of venous leg ulcer randomized controlled trials: Additional secondary analysis

In this secondary analysis of a previous systematic review, we assessed randomized controlled trials evaluating treatments of venous leg ulcers in terms of factors that affect risk of bias at the study level and thus uncertainty of outcomes obtained from the interventions. Articles that assessed the wound bed condition in venous leg ulcers and that were published in English between 1998 and May 22, 2018 were previously searched in PubMed, Embase, CINAHL, CENTRAL, Scopus, Science Direct, and Web of Science. Duplicates and retracted articles were excluded. The following data were extracted to assess the risk of bias: treatment groups; primary and secondary endpoints that were statistically tested between groups, including their results and p values; whether blinding of patients and assessors was done; whether allocation concealment was adequate; whether an intention‐to‐treat analysis was conducted; whether an appropriate power calculation was correctly done; and whether an appropriate multiplicity adjustment was made, as necessary. Pre‐ and post‐study power calculations were made. The step‐up Hochberg procedure adjusted for multiplicity. Results were analysed for all studies, pre‐2013 studies, and 2013/post‐2013 studies. We included 142 randomized controlled trials that evaluated 14,141 patients. Most studies lacked blinding (72.5–77.5%) and allocation concealment (88.7%). Only 49.3% of trials provided a power calculation, with 27.5% having an appropriate calculation correctly done. Adequate statistical power of the primary endpoint was found in 27.2% of trials. The lack of multiplicity adjustment in 98.6% of studies affected the uncertainty of outcomes in 20% of studies, with the majority of the secondary endpoints (67.7%) in those studies becoming non‐significant after multiplicity adjustment. Recent studies tended to weakly demonstrate improved certainty of outcomes. Venous leg ulcer randomized controlled trials have a high degree of uncertainty associated with treatment outcomes. Greater attention to trial design and conduct is needed to improve the evidence base.

A classification of methods used to personalize participative interventions revealed inadequate reporting in trial protocols

OBJECTIVES

The objective of the study was to develop a classification of methods used to personalize participative interventions in randomized controlled trials (RCTs).

STUDY DESIGN AND SETTING

We conducted a systematic review including protocols of RCTs assessing participative interventions in PubMed and ClinicalTrials.gov between June 2018 and May 2019. Data extraction was performed by two independent reviewers. We developed a precise classification of methods used to personalize interventions. Then, protocols were reviewed to determine whether personalization was sufficiently described to enable replication.

RESULTS

We included 109 protocols. The classification used four components and 13 subcomponents accounting for decision points (when interventions were personalized), tailoring variables (on what interventions were personalized), decision rules (how and by whom interventions were personalized), and nature of the subsequent tailoring (what was personalized in the interventions). In 95% of protocols, at least one component or subcomponent of our classification was not adequately reported to enable the replication of the intervention. Components the least well described were tailoring variables (72% of protocols insufficiently described) and the nature of the subsequent tailoring (46% of protocols).

CONCLUSION

This study provides the first detailed classification of methods used to personalize interventions. This is required to transparently implement personalization and improve reporting in RCTs.

Rescue and concomitant analgesics in placebo-controlled trials of pharmacotherapy for neuropathic pain and low back pain

Rescue medication is commonly offered to participants in placebo-controlled trials of analgesic drugs. The use of pain medication in addition to the placebo or experimental drug may complicate the interpretation of effects and tolerability, but this issue has received little methodological attention. This study examined the handling and reporting of rescue and concomitant analgesic use in trials of pharmacotherapy for neuropathic pain and low back pain. We based our review on 265 trials included in 2 recent systematic reviews: 83 trials of low back pain and 182 of neuropathic pain. In total, 117 (44%) trials permitted rescue medication and 126 (48%) allowed participants to continue all or some of their usual analgesics. The utilization of rescue medication increased over time, occurring in 18% of trials before 2000 compared with 55% after 2000. Forty-one trials (16%) permitted both rescue analgesics and continued use of prestudy analgesics. More than one-third of the trials permitting rescue medication did not report the actual rescue drug consumption, and over half of the trials allowing concomitant analgesics did not report whether intake changed during the trial. Only 22 (19%) of the trials permitting rescue medication included complete information about whether rescue medication was used as an outcome, specified the drugs used, specified how consumption was assessed and measured, and reported and analyzed the use of rescue medication in each trial arm. Our findings suggest that poorly described procedures and incomplete reporting are likely to hinder the interpretation, critical appraisal, and replication of trial results.

Does veneering technique affect the bond strength of bilayer Y-TZP? A systematic review and meta-analysis

STATEMENT OF PROBLEM

Reasons for failures of bilayer yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) restorations include the core-veneer interface bond strength. The influence of the veneering method on the bond strength of veneered Y-TZP is unclear.

PURPOSE

The purpose of this systematic review and meta-analysis was to evaluate the effect of the veneering method on the bond strength of bilayer Y-TZP.

MATERIAL AND METHODS

This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Searches were performed on PubMed/MEDLINE, Web of Science (Core Collection), and Scopus for in vitro studies evaluating the effect of the veneering technique on the bond strength of bilayer Y-TZP. Statistical analyses were performed with random-effect models (α=.05).

RESULTS

From 619 identified studies, 140 were selected for full-text analysis and 16 were included. Manual searching yielded no additional articles. The meta-analyses comprised 15 studies, and 1 study was included only in the descriptive analysis. Meta-analyses compared the hand-layered method (control) with pressed, fused, and cemented veneering methods. The fused and cemented techniques were analyzed by using subgroups assessing the veneering ceramic type (predominantly glass-ceramics and particle-filled glass-ceramics). Similar bond strength results (P=.540) were found for pressed and hand-layered veneered Y-TZP specimens. Fused veneers achieved higher bond strength values (P<.001) than the hand-layered veneers on Y-TZP frameworks, irrespective of the veneering ceramic type (predominantly glass-ceramics: P=.002; particle-filled glass-ceramics: P<.001). Global and subgroup analyses indicated that lower core-veneer bond strength values (P<.001) were found for cemented in relation to hand-layered veneers.

CONCLUSIONS

Core-veneer interfacial adhesion was equivalent for pressed and hand-layered veneering techniques. Improved bond strength, regardless of the veneer ceramic material type, was achieved by the fused veneering method, which seems to be a promising choice for the veneering of Y-TZP. In contrast, the cemented method may be unsuitable for veneering Y-TZP structures because of its lower bond strength than the hand-layered veneering technique.

Citicoline for treating people with acute ischemic stroke

BACKGROUND

Stroke is one of the leading causes of long-lasting disability and mortality and its global burden has increased in the past two decades. Several therapies have been proposed for the recovery from, and treatment of, ischemic stroke. One of them is citicoline. This review assessed the benefits and harms of citicoline for treating patients with acute ischemic stroke.

OBJECTIVES

To assess the clinical benefits and harms of citicoline compared with placebo or any other control for treating people with acute ischemic stroke.

SEARCH METHODS

We searched in the Cochrane Stroke Group Trials Register, CENTRAL, MEDLINE Ovid, Embase Ovid, LILACS until 29 January 2020. We searched the World Health Organization Clinical Trials Search Portal and ClinicalTrials.gov. Additionally, we also reviewed reference lists of the retrieved publications and review articles, and searched the websites of the US Food and Drug Administration (FDA) and European Medicines Agency (EMA).

SELECTION CRITERIA

We included randomized controlled trials (RCTs) in any setting including participants with acute ischemic stroke. Trials were eligible for inclusion if they compared citicoline versus placebo or no intervention.

DATA COLLECTION AND ANALYSIS

We selected RCTs, assessed the risk of bias in seven domains, and extracted data by duplicate. Our primary outcomes of interest were all-cause mortality and the degree of disability or dependence in daily activities at 90 days. We estimated risk ratios (RRs) for dichotomous outcomes. We measured statistical heterogeneity using the I² statistic. We conducted our analyses using the fixed-effect and random-effects model meta-analyses. We assessed the overall quality of evidence for six pre-specified outcomes using the GRADE approach.

MAIN RESULTS

We identified 10 RCTs including 4281 participants. In all these trials, citicoline was given either orally, intravenously, or a combination of both compared with placebo or standard care therapy. Citicoline doses ranged between 500 mg and 2000 mg per day. We assessed all the included trials as having high risk of bias. Drug companies sponsored six trials. A pooled analysis of eight trials indicates there may be little or no difference in all-cause mortality comparing citicoline with placebo (17.3% versus 18.5%; RR 0.94, 95% CI 0.83 to 1.07; I² = 0%; low-quality evidence due to risk of bias). Four trials found no difference in the proportion of patients with disability or dependence in daily activities according to the Rankin scale comparing citicoline with placebo (21.72% versus 19.23%; RR 1.11, 95% CI 0.97 to 1.26; I² = 1%; low-quality evidence due to risk of bias). Meta-analysis of three trials indicates there may be little or no difference in serious cardiovascular adverse events comparing citicoline with placebo (8.83% versus 7.77%; RR 1.04, 95% CI 0.84 to 1.29; I² = 0%; low-quality evidence due to risk of bias). Overall, either serious or non-serious adverse events - central nervous system, gastrointestinal, musculoskeletal, etc. - were poorly reported and harms may have been underestimated. Four trials assessing functional recovery with the Barthel Index at a cut-off point of 95 points or more did not find differences comparing citicoline with placebo (32.78% versus 30.70%; RR 1.03, 95% CI 0.94 to 1.13; I² = 24%; low-quality evidence due to risk of bias). There were no differences in neurological function (National Institutes of Health Stroke Scale at a cut-off point of ≤ 1 points) comparing citicoline with placebo according to five trials (24.31% versus 22.44%; RR 1.08, 95% CI 0.96 to 1.21; I² = 27%, low-quality evidence due to risk of bias). A pre-planned Trial Sequential Analysis suggested that no more trials may be needed for the primary outcomes but no trial provided information on quality of life.

AUTHORS' CONCLUSIONS

This review assessed the clinical benefits and harms of citicoline compared with placebo or any other standard treatment for people with acute ischemic stroke. The findings of the review suggest there may be little to no difference between citicoline and its controls regarding all-cause mortality, disability or dependence in daily activities, severe adverse events, functional recovery and the assessment of the neurological function, based on low-certainty evidence. None of the included trials assessed quality of life and the safety profile of citicoline remains unknown. The available evidence is of low quality due to either limitations in the design or execution of the trials.

Has the reporting quality of published randomised controlled trial protocols improved since the SPIRIT statement? A methodological study

OBJECTIVES

To determine the reporting quality of published randomised controlled trial (RCT) protocols before and after the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) statement (2013), and any association with author, trial or journal factors.

DESIGN

Methodological study.

DATA SOURCES

MEDLINE, Embase and CENTRAL were electronically searched using optimised search strategies.

ELIGIBILITY CRITERIA

Protocols written for an RCT of living humans, published in full text in a peer-reviewed journal and published in the English language.

MAIN OUTCOME

Primary outcome was the overall proportion of checklist items which were adequately reported in RCT protocols published before and after the SPIRIT statement.

RESULTS

300 RCT protocols were retrieved; 150 from the period immediately before the SPIRIT statement (9 July 2012 to 28 December 2012) and 150 from a recent period after the SPIRIT statement (25 January 2019 to 20 March 2019). 47.9% (95% CI, 46.5% to 49.3%) of checklist items were adequately reported in RCT protocols before the SPIRIT statement and 56.7% (95% CI, 54.9% to 58.5%) after the SPIRIT statement. This represents an 8.8% (95% CI, 6.6% to 11.1%; p<0.0001) mean improvement in the overall proportion of checklist items adequately reported since the SPIRIT statement. While 40% of individual checklist items had a significant improvement in adequate reporting after the SPIRIT statement, 11.3% had a significant deterioration and there were no RCT protocols in which all individual checklist items were complete. The factors associated with higher reporting quality of RCT protocols in multiple regression analysis were author expertise or experience in epidemiology or statistics, multicentre trials, longer protocol word length and publicly reported journal policy of compliance with the SPIRIT statement.

CONCLUSION

The overall reporting quality of RCT protocols has significantly improved since the SPIRIT statement, although a substantial proportion of individual checklist items remain poorly reported. Continued and concerted efforts are required by journals, editors, reviewers and investigators to improve the completeness and transparency of RCT protocols.

Inter-review agreement of risk-of-bias judgments varied in Cochrane reviews

OBJECTIVES

The objective of the study was to measure the level of agreement between Cochrane reviews of overlapping randomized controlled trials (RCTs) regarding risk-of-bias (RoB) judgments.

STUDY DESIGN AND SETTING

On November 5, 2017, the Cochrane Database of Systematic Reviews was searched for Cochrane reviews on tobacco. Reviews that included overlapping RCTs were included. RoB judgments were extracted from RoB tables using automated data scraping with manual verification and adjustments. Agreement between the reviews was calculated using Conger's generalized kappa coefficient (κ) and raw agreement (a).

RESULTS

We included 53 Cochrane reviews of 376 RCTs. For the RoB domain "random sequence generation," the level of agreement between the reviews was substantial with κ = 0.63 (95% confidence interval: 0.56 to 0.71; a = 0.80). There was slight-to-moderate agreement between the reviews regarding the domains "allocation concealment": κ = 0.51 (0.41 to 0.61), a = 0.75; "blinding": κ = 0.19 (0.02 to 0.37), a = 0.52; "blinding of outcome assessment": κ = 0.43 (0.14 to 0.72) a = 0.67; and "incomplete outcome data": κ = 0.15 (-0.03 to 0.32), a = 0.64. For "blinding of participants and personnel" and "selective reporting", κ could not be calculated. The raw agreement was 0.40 and 0.42, respectively.

CONCLUSION

The level of agreement between Cochrane reviews regarding RoB judgments ranged from slight to substantial depending on the RoB domain. Further investigations regarding reasons for variation and interventions to improve agreement are needed.

Design characteristics, risk of bias, and reporting of randomised controlled trials supporting approvals of cancer drugs by European Medicines Agency, 2014-16: cross sectional analysis

OBJECTIVE

To examine the design characteristics, risk of bias, and reporting adequacy of pivotal randomised controlled trials of cancer drugs approved by the European Medicines Agency (EMA).

DESIGN

Cross sectional analysis.

SETTING

European regulatory documents, clinical trial registry records, protocols, journal publications, and supplementary appendices.

ELIGIBILITY CRITERIA

Pivotal randomised controlled trials of new cancer drugs approved by the EMA between 2014 and 2016.

MAIN OUTCOME MEASURES

Study design characteristics (randomisation, comparators, and endpoints); risk of bias using the revised Cochrane tool (bias arising from the randomisation process, deviations from intended interventions, missing outcome data, measurement of the outcome, and selection of the reported result); and reporting adequacy (completeness and consistency of information in trial protocols, publications, supplementary appendices, clinical trial registry records, and regulatory documents).

RESULTS

Between 2014 and 2016, the EMA approved 32 new cancer drugs on the basis of 54 pivotal studies. Of these, 41 (76%) were randomised controlled trials and 13 (24%) were either non-randomised studies or single arm studies. 39/41 randomised controlled trials had available publications and were included in our study. Only 10 randomised controlled trials (26%) measured overall survival as either a primary or coprimary endpoint, with the remaining trials evaluating surrogate measures such as progression free survival and response rates. Overall, 19 randomised controlled trials (49%) were judged to be at high risk of bias for their primary outcome. Concerns about missing outcome data (n=10) and measurement of the outcome (n=7) were the most common domains leading to high risk of bias judgments. Fewer randomised controlled trials that evaluated overall survival as the primary endpoint were at high risk of bias than those that evaluated surrogate efficacy endpoints (2/10 (20%) v 16/29 (55%), respectively). When information available in regulatory documents and the scientific literature was considered separately, overall risk of bias judgments differed for eight randomised controlled trials (21%), which reflects reporting inadequacies in both sources of information. Regulators identified additional deficits beyond the domains captured in risk of bias assessments for 10 drugs (31%). These deficits included magnitude of clinical benefit, inappropriate comparators, and non-preferred study endpoints, which were not disclosed as limitations in scientific publications.

CONCLUSIONS

Most pivotal studies forming the basis of EMA approval of new cancer drugs between 2014 and 2016 were randomised controlled trials. However, almost half of these were judged to be at high risk of bias based on their design, conduct, or analysis, some of which might be unavoidable because of the complexity of cancer trials. Regulatory documents and the scientific literature had gaps in their reporting. Journal publications did not acknowledge the key limitations of the available evidence identified in regulatory documents.

Overall bias and sample sizes were unchanged in ICU trials over time: a meta-epidemiological study

OBJECTIVE

To assess time trends in risk of bias (RoB) and sample sizes in randomized clinical trials (RCTs) of adult intensive care unit (ICU) patients.

STUDY DESIGN AND SETTING

A meta-epidemiological study of RCTs from Cochrane systematic reviews assessing interventions in adult ICU patients. Using run charts, we assessed time trends in the annual proportion of RCTs with overall low RoB, the annual median sample sizes, and the annual proportion of RCTs with low, unclear, and high RoB in individual bias domains.

RESULTS

We included 604 RCTs published between 1977 and 2018 from 53 Cochrane systematic reviews. Only 6.8% of the RCTs had overall low RoB. We observed only random variation in the annual proportions of RCTs with overall low RoB, in the annual median sample sizes and in most individual bias domains. For "allocation concealment," we observed an increase in the proportion of low RoB RCTs and a decrease in the unclear RoB RCTs.

CONCLUSIONS

Few RCTs in adult ICU patients had overall low RoB. We found no evidence of an increase in RCTs with overall low RoB or in the median sample sizes over time. The only individual RoB domain with better ratings over time was "allocation concealment."

Vitamin C Can Shorten the Length of Stay in the ICU: A Meta-Analysis

A number of controlled trials have previously found that in some contexts, vitamin C can have beneficial effects on blood pressure, infections, bronchoconstriction, atrial fibrillation, and acute kidney injury. However, the practical significance of these effects is not clear. The purpose of this meta-analysis was to evaluate whether vitamin C has an effect on the practical outcomes: length of stay in the intensive care unit (ICU) and duration of mechanical ventilation. We identified 18 relevant controlled trials with a total of 2004 patients, 13 of which investigated patients undergoing elective cardiac surgery. We carried out the meta-analysis using the inverse variance, fixed effect options, using the ratio of means scale. In 12 trials with 1766 patients, vitamin C reduced the length of ICU stay on average by 7.8% (95% CI: 4.2% to 11.2%; p = 0.00003). In six trials, orally administered vitamin C in doses of 1⁻3 g/day (weighted mean 2.0 g/day) reduced the length of ICU stay by 8.6% (p = 0.003). In three trials in which patients needed mechanical ventilation for over 24 hours, vitamin C shortened the duration of mechanical ventilation by 18.2% (95% CI 7.7% to 27%; p = 0.001). Given the insignificant cost of vitamin C, even an 8% reduction in ICU stay is worth exploring. The effects of vitamin C on ICU patients should be investigated in more detail.

Bias and sample size in intensive care unit trials: Protocol for a meta-epidemiological study

BACKGROUND

Systematic errors (bias) and random errors result in inflated and imprecise intervention effect estimates in randomised clinical trials (RCT) and meta-analyses. We aim to assess time trends in the Cochrane risk of bias domains and sample size in RCTs of intensive care unit (ICU) interventions.

METHODS AND DESIGN

We will conduct a meta-epidemiologic study of RCTs included in Cochrane systematic reviews assessing any intervention used in adult patients admitted to the ICU. We will search the Cochrane Database of Systematic Reviews and include reviews published from March 2011 corresponding to the latest update in the Cochrane risk of bias tool. We will extract data on risk of bias judgments in the seven Cochrane bias domains and trial sample sizes and evaluate time trends using run charts. The primary outcome will be time trends in the annual proportion of trials with overall low risk of bias (low risk of bias in all bias domains). The secondary outcomes include time trends in the annual median trial sample size, and the annual proportion of trials with low-, unclear- and high risk of bias in each of the seven Cochrane bias domains.

DISCUSSION

The outlined meta-epidemiologic study will assess time trends in risk of bias and sample sizes in RCTs assessing ICU interventions. This will inform researchers, healthcare personnel and policymakers on the general reliability of findings from RCTs of ICU interventions over time, and inform future RCT design and reporting.

The relationship between childhood adversities and dissociation in severe mental illness: a meta-analytic review

OBJECTIVE

Several studies have observed that dissociative experiences are frequently reported by individuals with severe mental illness (SMI), especially amongst patients that report a history of adverse/traumatic life experiences. This review examined the magnitude and consistency of the relationship between childhood adversity (sexual abuse, physical abuse, emotional abuse, neglect, bullying, natural disasters and mass violence) and dissociation across three SMI diagnostic groups: schizophrenia, bipolar disorder and personality disorders.

METHOD

A database search (EMBASE, PubMed and PsycINFO) identified 30 eligible empirical studies, comprising of 2199 clinical participants. Effect sizes representing the relationship between exposure to childhood adversity and dissociation were examined and integrated using a random-effects meta-analysis.

RESULTS

The results indicated that exposure to childhood trauma was associated with heightened dissociation across SMIs. Positive significant associations were also found between specific childhood adversities and dissociation, with aggregated effect sizes in the small-to-moderate range.

CONCLUSION

These findings support calls for the routine assessment of traumatic experiences in clients with SMIs presenting with dissociative symptoms and the provision of adequate therapeutic support (e.g. trauma-focused therapies) to manage and resolve these difficulties.

Physical Activity Preferences Among Older Adults: A Systematic Review

The objective of this study was to identify preferences for physical activity among adults aged 65 years and over. A systematic review was conducted. A search strategy without language and date restriction (up until March 31, 2017) was developed for PubMed, CINAHL, PsycINFO, ERIC, and SPORTDiscus. Study selection and data extraction were performed independently by two reviewers. A total of 21 independent primary studies were included in the systematic review. Irrespective of the methodologies used and samples, a majority of older adults prefer to walk and engage in physical activity continuously for about 30 min. These findings are mainly generalizable to White females from the United States. Two-thirds of the studies were at high risk of selection bias, which suggests additional caution when interpreting the review findings. Nonetheless, policymakers, community organizations, and healthcare providers should consider walkability in their efforts to promote physical activity in older adults.

Impact of missing individual patient data on 18 meta-analyses of randomised trials in oncology: Gustave Roussy experience

OBJECTIVE

To compare the characteristics, quality and treatment effects of randomised clinical trials (RCTs) by individual patient data (IPD) availability, in trials eligible for 18 IPD meta-analyses (MA).

DESIGN

Trial characteristics, risk of bias (RoB) and hazard ratio (HR) for overall survival were extracted from IPD-MA publications and/or RCTs publications. Data for the RoB assessment were extracted for a subset of 73 RCTs. Two investigators blinded to whether IPD was available or not evaluated the RoB for these trials. Treatment effects were compared using ratios of global HRs (RHRs) of IPD-unavailable trials and IPD-available trials. RHR were pooled using a fixed-effect model.

DATA SOURCES

We examined the IPD availability for each trial eligible for each IPD-MA; when the IPD was not available for a trial, we used information from published sources.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

We selected all published IPD-MAs conducted at Gustave Roussy and the RCTs eligible for each.

RESULTS

349 RCTs (73 018 patients) from 18 MAs were eligible: 60 RCTs (5890 patients) had unavailable IPD and 289 RCTs (67 128 patients) had available IPD. The main reason for IPD unavailability was data loss by investigators. IPD-unavailable trials were smaller (p<0.001), more often monocentric (p<0.001) and non-international (p=0.0004) than IPD-available trials. Geographical areas differed (p=0.054) between IPD-unavailable IPD-available trials. RoB was higher in IPD-unavailable RCTs for random sequence generation (p=0.007) and allocation concealment (p=0.006). The HR and 95% confidence interval (CI) for overall survival were extractable from publications in 23/60 IPD-unavailable trials included in 10 different MAs. Treatment effects were significantly greater for IPD-unavailable trials compared with IPD-available trials (RHR=0.86 (95% CI 0.75 to 0.98)).

CONCLUSIONS

IPD-unavailable RCTs were significantly different from IPD-available RCTs in terms of trial characteristics and were at greater RoB. IPD-unavailable RCTs had a significantly greater treatment effect.

Improving the usefulness of a tool for appraising the quality of qualitative, quantitative and mixed methods studies, the Mixed Methods Appraisal Tool (MMAT)

RATIONALE, AIMS, AND OBJECTIVES

Systematic reviews combining qualitative, quantitative, and/or mixed methods studies are increasingly popular because of their potential for addressing complex interventions and phenomena, specifically for assessing and improving clinical practice. A major challenge encountered with this type of review is the appraisal of the quality of individual studies given the heterogeneity of the study designs. The Mixed Methods Appraisal Tool (MMAT) was developed to help overcome this challenge. The aim of this study was to explore the usefulness of the MMAT by seeking the views and experiences of researchers who have used it.

METHODS

We conducted a qualitative descriptive study using semistructured interviews with MMAT users. A purposeful sample was drawn from the researchers who had previously contacted the developer of the MMAT, and those who have published a systematic review for which they had used the MMAT. All interviews were transcribed verbatim and analyzed by 2 coders using thematic analysis.

RESULTS

Twenty participants from 8 countries were interviewed. Thirteen themes were identified and grouped into the 2 dimensions of usefulness, ie, utility and usability. The themes related to utility concerned the coverage, completeness, flexibility, and other utilities of the tool. Those regarding usability were related to the learnability, efficiency, satisfaction, and errors that could be made due to difficulties understanding or selecting the items to appraise.

CONCLUSIONS

On the basis of the results of this study, we make several recommendations for improving the MMAT. This will contribute to greater usefulness of the MMAT.

Does veneering technique affect the flexural strength or load-to-failure of bilayer Y-TZP? A systematic review and meta-analysis

STATEMENT OF PROBLEM

Causes of failures of bilayer yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) restorations include the processing technique and the properties of the veneer ceramic. The effect of the veneering method on the mechanical behavior of veneered Y-TZP remains unclear.

PURPOSE

The purpose of this systematic review was to assess the effect of the veneering method on the flexural strength and failure load of bilayer Y-TZP.

MATERIAL AND METHODS

This study followed the Preferred Reporting Items for the Systematic Reviews and Meta-Analyses (PRISMA) statement. Searches were performed through August 2017 in PubMed/MEDLINE, Web of Science (Core Collection), Scopus, and Embase, with no year or language limit, targeting in vitro studies evaluating the effect of the veneering technique on the flexural strength and load-to-failure of bilayer Y-TZP immediately or after aging. Statistical analyses were conducted using an appropriate software. Comparisons were drawn with random effect models (α=.05).

RESULTS

From 3242 identified studies, 241 were selected for full-text analysis; from these, 33 studies were included. Manual searching yielded no additional papers. The meta-analysis consisted of 32 studies. Meta-analysis was performed separately for flexural strength and failure load data to compare the hand-layered method (control) with pressed, fused, and cemented veneering techniques. The cemented and fused methods were analyzed using subgroups depending on the veneering material being examined (predominantly glass-ceramics and particle-filled glass-ceramics), and the results were compared with those of the hand-layered method. The pressed group presented flexural strength (7 studies) (P=.150) and failure load (19 studies) (P=.140) values that were similar to those of the hand-layered group. Subgroup analysis revealed that the fused group with particle-filled glass-ceramics (7 studies) produced higher load-to-failure (P=.006) values than the hand-layered group. Subgroup analyses showed a statistical difference that favored the hand-layered over the cemented method, with predominantly glass-ceramic materials (5 studies) (P=.002).

CONCLUSIONS

The fused technique with particle-filled glass-ceramics seems more appropriate for the veneering of Y-TZP, with improved failure load, than the hand-layered method with predominantly glass-ceramic materials. The use of predominantly glass-ceramics for the cemented method is not recommended as failure load was lower than for the hand-layered group. Pressed veneers showed failure load and flexural strength values similar to those of the the hand-layered technique.

Exploring the characteristics, global distribution and reasons for retraction of published articles involving human research participants: a literature survey

Aim

Article retraction is a measure taken by journals or authors where there is evidence of research misconduct or error, redundancy, plagiarism or unethical research. Recently, the retraction of scientific publications has been on the rise. In this survey, we aimed to describe the characteristics and distribution of retracted articles and the reasons for retractions.

Methods

We searched retracted articles on the PubMed database and Retraction Watch website from 1980 to February 2016. The primary outcomes were the characteristics and distribution of retracted articles and the reasons for retractions. The secondary outcomes included how article retractions were handled by journals and how to improve the journal practices toward article retractions.

Results

We included 1,339 retracted articles. Most retracted articles had six authors or fewer. Article retraction was most common in the USA (26%), Japan (11%) and Germany (10%). The main reasons for article retraction were misconduct (51%, n = 685) and error (14%, n = 193). There were 66% (n = 889) of retracted articles having male senior or corresponding authors. Of the articles retracted after August 2010, 63% (n = 567) retractions were reported on Retraction Watch. Large discrepancies were observed in the ways that different journals handled article retractions. For instance, articles were completely withdrawn from some journals, while in others, articles were still available with no indication of retraction. Likewise, some retraction notices included a detailed account of the events that led to article retraction, while others only consisted of a statement indicating the article retraction.

Conclusion

The characteristics, geographic distribution and reasons for retraction of published articles involving human research participants were examined in this survey. More efforts are needed to improve the consistency and transparency of journal practices toward article retractions.

A systematic review of comparisons between protocols or registrations and full reports in primary biomedical research

BACKGROUND

Prospective study protocols and registrations can play a significant role in reducing incomplete or selective reporting of primary biomedical research, because they are pre-specified blueprints which are available for the evaluation of, and comparison with, full reports. However, inconsistencies between protocols or registrations and full reports have been frequently documented. In this systematic review, which forms part of our series on the state of reporting of primary biomedical, we aimed to survey the existing evidence of inconsistencies between protocols or registrations (i.e., what was planned to be done and/or what was actually done) and full reports (i.e., what was reported in the literature); this was based on findings from systematic reviews and surveys in the literature.

METHODS

Electronic databases, including CINAHL, MEDLINE, Web of Science, and EMBASE, were searched to identify eligible surveys and systematic reviews. Our primary outcome was the level of inconsistency (expressed as a percentage, with higher percentages indicating greater inconsistency) between protocols or registration and full reports. We summarized the findings from the included systematic reviews and surveys qualitatively.

RESULTS

There were 37 studies (33 surveys and 4 systematic reviews) included in our analyses. Most studies (n = 36) compared protocols or registrations with full reports in clinical trials, while a single survey focused on primary studies of clinical trials and observational research. High inconsistency levels were found in outcome reporting (ranging from 14% to 100%), subgroup reporting (from 12% to 100%), statistical analyses (from 9% to 47%), and other measure comparisons. Some factors, such as outcomes with significant results, sponsorship, type of outcome and disease speciality were reported to be significantly related to inconsistent reporting.

CONCLUSIONS

We found that inconsistent reporting between protocols or registrations and full reports of primary biomedical research is frequent, prevalent and suboptimal. We also identified methodological issues such as the need for consensus on measuring inconsistency across sources for trial reports, and more studies evaluating transparency and reproducibility in reporting all aspects of study design and analysis. A joint effort involving authors, journals, sponsors, regulators and research ethics committees is required to solve this problem.

Quality of Randomized Controlled Trials Reporting in the Treatment of Adult Patients with High-Grade Gliomas

BACKGROUND

The randomized controlled trial (RCT) is the gold standard to objectively assess the effect of treatments. To help improve the quality of RCTs, experts established a list of recommendations, the CONsolidated Standards of Reporting Trials (CONSORT) Statement. In this study, we evaluated the implementation of the CONSORT Statement in the field of high-grade gliomas in adult patients and looked for criteria associated with higher quality of RCTs.

MATERIALS AND METHODS

We searched all high-grade gliomas RCTs published in PubMed between January 1990 and December 2016. The quality of these RCTs was assessed by completing a modified CONSORT Score (CS).

RESULTS

Ninety-six published RCTs were identified. The median CS was 19.5 on a scale of 0-33. Items were not equally reported. Items regarding the method of randomization or the blinding were reported in less than 25% of RCTs. However, the CS has constantly improved over the years. Before the implementation of the CONSORT Statement in 1996, the median CS was 13, whereas it was 17 for the period 1996-2004 and 22 after 2005. A higher CS was observed when RCTs were published in a journal with an impact factor above 10 (p < .001) or after 2010 (p = .001), when the primary outcome was clearly defined (p < .001) and for RCTs that enrolled more than 200 patients (p = .004).

CONCLUSION

Although there has been a steady improvement in the CS over the years in the field of high-grade gliomas, a major effort must be made in the reporting methods for randomization and blinding.

IMPLICATIONS FOR PRACTICE

This study showed that the quality of reporting of randomized control trials (RCTs) concerning the treatment of high-grade gliomas is poor. Factors associated with a better quality of reports were identified and should be incorporated into the design of future RCTs. When clinicians read the results of RCTs, they should be aware of the possible inadequate reporting from these trials and take it into account for the management of their patients. This study identifies how RCTs can be improved in their reporting but also in their design, in order to advance care for patients with high-grade gliomas in the future.

Current practice in methodology and reporting of the sample size calculation in randomised trials of hip and knee osteoarthritis: a protocol for a systematic review

Background

A key aspect of the design of randomised controlled trials (RCTs) is determining the sample size. It is important that the trial sample size is appropriately calculated. The required sample size will differ by clinical area, for instance, due to the prevalence of the condition and the choice of primary outcome. Additionally, it will depend upon the choice of target difference assumed in the calculation. Focussing upon the hip and knee osteoarthritis population, this study aims to systematically review how the trial size was determined for trials of osteoarthritis, on what basis, and how well these aspects are reported.

Methods

Several electronic databases (Medline, Cochrane library, CINAHL, EMBASE, PsycINFO, PEDro and AMED) will be searched to identify articles on RCTs of hip and knee osteoarthritis published in 2016. Articles will be screened for eligibility and data extracted independently by two reviewers. Data will be extracted on study characteristics (design, population, intervention and control treatments), primary outcome, chosen sample size and justification, parameters used to calculate the sample size (including treatment effect in control arm, level of variability in primary outcome, loss to follow-up rates). Data will be summarised across the studies using appropriate summary statistics (e.g. n and %, median and interquartile range). The proportion of studies which report each key component of the sample size calculation will be presented. The reproducibility of the sample size calculation will be tested.

Discussion

The findings of this systematic review will summarise the current practice for sample size calculation in trials of hip and knee osteoarthritis. It will also provide evidence on the completeness of the reporting of the sample size calculation, reproducibility of the chosen sample size and the basis for the values used in the calculation.

Trial registration

As this review was not eligible to be registered on PROSPERO, the summary information was uploaded to Figshare to make it publicly accessible in order to avoid unnecessary duplication amongst other benefits (https://doi.org/10.6084/m9.figshare.5009027.v1); Registered January 17, 2017.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2209-8) contains supplementary material, which is available to authorized users.

METHODOLOGICAL QUALITY OF ECONOMIC EVALUATIONS ALONGSIDE TRIALS OF KNEE PHYSIOTHERAPY

OBJECTIVES

The methodological quality of an economic evaluation performed alongside a clinical trial can be underestimated if the paper does not report key methodological features. This study discusses methodological assessment issues on the example of a systematic review on cost-effectiveness of physiotherapy for knee osteoarthritis.

METHODS

Six economic evaluation studies included in the systematic review and related clinical trials were assessed using the 10-question check-list by Drummond and the Physiotherapy Evidence Database (PEDro) scale.

RESULTS

All economic evaluations were performed alongside a clinical trial but the studied interventions were too heterogeneous to be synthesized. Methodological quality of the economic evaluations reported in the papers was not free of drawbacks, and in some cases, it improved when information from the related clinical trial was taken into account.

CONCLUSIONS

Economic evaluation papers dedicate little space to methodological features of related clinical trials; therefore, the methodological quality can be underestimated if evaluated separately from the trials. Future economic evaluations should follow more strictly the recommendations about methodology and the authors should pay special attention to the quality of reporting.

Impact of Selection Bias on Treatment Effect Size Estimates in Randomized Trials of Oral Health Interventions: A Meta-epidemiological Study

Emerging evidence suggests that design flaws of randomized controlled trials can result in over- or underestimation of the treatment effect size (ES). The objective of this study was to examine associations between treatment ES estimates and adequacy of sequence generation, allocation concealment, and baseline comparability among a sample of oral health randomized controlled trials. For our analysis, we selected all meta-analyses that included a minimum of 5 oral health randomized controlled trials and used continuous outcomes. We extracted data, in duplicate, related to items of selection bias (sequence generation, allocation concealment, and baseline comparability) in the Cochrane Risk of Bias tool. Using a 2-level meta-meta-analytic approach with a random effects model to allow for intra- and inter-meta-analysis heterogeneity, we quantified the impact of selection bias on the magnitude of ES estimates. We identified 64 meta-analyses, including 540 randomized controlled trials analyzing 137,957 patients. Sequence generation was judged to be adequate (at low risk of bias) in 32% ( n = 173) of trials, and baseline comparability was judged to be adequate in 77.8% of trials. Allocation concealment was unclear in the majority of trials ( n = 458, 84.8%). We identified significantly larger treatment ES estimates in trials that had inadequate/unknown sequence generation (difference in ES = 0.13; 95% CI: 0.01 to 0.25) and inadequate/unknown allocation concealment (difference in ES = 0.15; 95% CI: 0.02 to 0.27). In contrast, baseline imbalance (difference in ES = 0.01, 95% CI: –0.09 to 0.12) was not associated with inflated or underestimated ES. In conclusion, treatment ES estimates were 0.13 and 0.15 larger in trials with inadequate/unknown sequence generation and inadequate/unknown allocation concealment, respectively. Therefore, authors of systematic reviews using oral health randomized controlled trials should perform sensitivity analyses based on the adequacy of sequence generation and allocation concealment.

Bedaquiline versus placebo for management of multiple drug-resistant tuberculosis: A systematic review

Background:

Multidrug-resistant tuberculosis (MDR-TB) is associated with significant morbidity and mortality. Bedaquiline is the first drug approved for treating MDR-TB.

Objectives:

We performed a systematic review and meta-analysis to summarize the totality of all available evidence on the efficacy of bedaquiline for the management of MDR-TB.

Materials and Methods:

We searched the following PubMed and Cochrane Registry of Clinical Trials. Randomized controlled trials (RCTs) with a parallel design comparing bedaquiline versus any treatment for the management of MDR-TB in adults were eligible for inclusion. Data were pooled under a random effects model.

Results:

Two trials published as three manuscripts with a total of 207 patients were included. As per the Cochrane risk of bias tool, majority of parameter were labeled as high or unclear risk of bias. Bedaquiline compared with placebo was associated with a statistically significant decrease in time to conversion of positive sputum culture to negative at 8 and 24 weeks with a significant increase in mortality on long-term follow-up. There was no difference in completion rates between bedaquiline and placebo.

Conclusion:

Bedaquiline is an effective treatment modality for MDR-TB but needs to be balanced against significant mortality. Future Phase 3 RCTs are needed to make a conclusive recommendation.

State of reporting of primary biomedical research: a scoping review protocol

INTRODUCTION

Incomplete or inconsistent reporting remains a major concern in the biomedical literature. Incomplete or inconsistent reporting may yield the published findings unreliable, irreproducible or sometimes misleading. In this study based on evidence from systematic reviews and surveys that have evaluated the reporting issues in primary biomedical studies, we aim to conduct a scoping review with focuses on (1) the state-of-the-art extent of adherence to the emerging reporting guidelines in primary biomedical research, (2) the inconsistency between protocols or registrations and full reports and (3) the disagreement between abstracts and full-text articles.

METHODS AND ANALYSES

We will use a comprehensive search strategy to retrieve all available and eligible systematic reviews and surveys in the literature. We will search the following electronic databases: Web of Science, Excerpta Medica Database (EMBASE), MEDLINE and Cumulative Index to Nursing and Allied Health Literature (CINAHL). Our outcomes are levels of adherence to reporting guidelines, levels of consistency between protocols or registrations and full reports and the agreement between abstracts and full reports, all of which will be expressed as percentages, quality scores or categorised rating (such as high, medium and low). No pooled analyses will be performed quantitatively given the heterogeneity of the included systematic reviews and surveys. Likewise, factors associated with improved completeness and consistency of reporting will be summarised qualitatively. The quality of the included systematic reviews will be evaluated using AMSTAR (a measurement tool to assess systematic reviews).

ETHICS AND DISSEMINATION

All findings will be published in peer-reviewed journals and relevant conferences. These results may advance our understanding of the extent of incomplete and inconsistent reporting, factors related to improved completeness and consistency of reporting and potential recommendations for various stakeholders in the biomedical community.

Review and publication of protocol submissions to Trials - what have we learned in 10 years?

Trials has 10 years of experience in providing open access publication of protocols for randomised controlled trials. In this editorial, the senior editors and editors-in-chief of Trials discuss editorial issues regarding managing trial protocol submissions, including the content and format of the protocol, timing of submission, approaches to tracking protocol amendments, and the purpose of peer reviewing a protocol submission. With the clarification and guidance provided, we hope we can make the process of publishing trial protocols more efficient and useful to trial investigators and readers.

Methodological reporting quality of randomized controlled trials: A survey of seven core journals of orthopaedics from Mainland China over 5 years following the CONSORT statement

BACKGROUND

In recent years, the number of randomized controlled trials (RCTs) in the field of orthopaedics is increasing in Mainland China. However, randomized controlled trials (RCTs) are inclined to bias if they lack methodological quality. Therefore, we performed a survey of RCT to assess: (1) What about the quality of RCTs in the field of orthopedics in Mainland China? (2) Whether there is difference between the core journals of the Chinese department of orthopedics and Orthopaedics Traumatology Surgery & Research (OTSR).

MATERIAL AND METHODS

This research aimed to evaluate the methodological reporting quality according to the CONSORT statement of randomized controlled trials (RCTs) in seven key orthopaedic journals published in Mainland China over 5 years from 2010 to 2014. All of the articles were hand researched on Chongqing VIP database between 2010 and 2014. Studies were considered eligible if the words "random", "randomly", "randomization", "randomized" were employed to describe the allocation way. Trials including animals, cadavers, trials published as abstracts and case report, trials dealing with subgroups analysis, or trials without the outcomes were excluded. In addition, eight articles selected from Orthopaedics Traumatology Surgery & Research (OTSR) between 2010 and 2014 were included in this study for comparison. The identified RCTs are analyzed using a modified version of the Consolidated Standards of Reporting Trials (CONSORT), including the sample size calculation, allocation sequence generation, allocation concealment, blinding and handling of dropouts.

RESULTS

A total of 222 RCTs were identified in seven core orthopaedic journals. No trials reported adequate sample size calculation, 74 (33.4%) reported adequate allocation generation, 8 (3.7%) trials reported adequate allocation concealment, 18 (8.1%) trials reported adequate blinding and 16 (7.2%) trials reported handling of dropouts. In OTSR, 1 (12.5%) trial reported adequate sample size calculation, 4 (50.0%) reported adequate allocation generation, 1 (12.5%) trials reported adequate allocation concealment, 2 (25.0%) trials reported adequate blinding and 5 (62.5%) trials reported handling of dropouts. There were statistical differences as for sample size calculation and handling of dropouts between papers from Mainland China and OTSR (P<0.05).

CONCLUSION

The findings of this study show that the methodological reporting quality of RCTs in seven core orthopaedic journals from the Mainland China is far from satisfaction and it needs to further improve to keep up with the standards of the CONSORT statement.

LEVEL OF EVIDENCE

Level III case control.

Empirical Evidence of Study Design Biases in Randomized Trials: Systematic Review of Meta-Epidemiological Studies

OBJECTIVE

To synthesise evidence on the average bias and heterogeneity associated with reported methodological features of randomized trials.

DESIGN

Systematic review of meta-epidemiological studies.

METHODS

We retrieved eligible studies included in a recent AHRQ-EPC review on this topic (latest search September 2012), and searched Ovid MEDLINE and Ovid EMBASE for studies indexed from Jan 2012-May 2015. Data were extracted by one author and verified by another. We combined estimates of average bias (e.g. ratio of odds ratios (ROR) or difference in standardised mean differences (dSMD)) in meta-analyses using the random-effects model. Analyses were stratified by type of outcome ("mortality" versus "other objective" versus "subjective"). Direction of effect was standardised so that ROR < 1 and dSMD < 0 denotes a larger intervention effect estimate in trials with an inadequate or unclear (versus adequate) characteristic.

RESULTS

We included 24 studies. The available evidence suggests that intervention effect estimates may be exaggerated in trials with inadequate/unclear (versus adequate) sequence generation (ROR 0.93, 95% CI 0.86 to 0.99; 7 studies) and allocation concealment (ROR 0.90, 95% CI 0.84 to 0.97; 7 studies). For these characteristics, the average bias appeared to be larger in trials of subjective outcomes compared with other objective outcomes. Also, intervention effects for subjective outcomes appear to be exaggerated in trials with lack of/unclear blinding of participants (versus blinding) (dSMD -0.37, 95% CI -0.77 to 0.04; 2 studies), lack of/unclear blinding of outcome assessors (ROR 0.64, 95% CI 0.43 to 0.96; 1 study) and lack of/unclear double blinding (ROR 0.77, 95% CI 0.61 to 0.93; 1 study). The influence of other characteristics (e.g. unblinded trial personnel, attrition) is unclear.

CONCLUSIONS

Certain characteristics of randomized trials may exaggerate intervention effect estimates. The average bias appears to be greatest in trials of subjective outcomes. More research on several characteristics, particularly attrition and selective reporting, is needed.

From protocol to published report: a study of consistency in the reporting of academic drug trials

BACKGROUND

Unacknowledged inconsistencies in the reporting of clinical trials undermine the validity of the results of the trials. Little is known about inconsistency in the reporting of academic clinical drug trials. Therefore, we investigated the prevalence of consistency between protocols and published reports of academic clinical drug trials.

METHODS

A comparison was made between study protocols and their corresponding published reports. We assessed the overall consistency, which was defined as the absence of discrepancy regarding study type (categorized as either exploratory or confirmatory), primary objective, primary endpoint, and--for confirmatory trials only--hypothesis and sample size calculation. We used logistic regression, χ(2), and Fisher's exact test.

RESULTS

A total of 282 applications of academic clinical drug trials were submitted to the Danish Health and Medicines Authority in 1999, 2001, and 2003, 95 of which fulfilled the eligibility criteria and had at least one corresponding published report reporting data on trial subjects. Overall consistency was observed in 39% of the trials (95% CI: 29 to 49%). Randomized controlled trials (RCTs) constituted 72% (95% CI: 63 to 81%) of the sample, and 87% (95% CI: 80 to 94%) of the trials were hospital based.

CONCLUSIONS

Overall consistency between protocols and their corresponding published reports was low. Motivators for the inconsistencies are unknown but do not seem restricted to economic incentives.