Adequacy of risk of bias assessment in surgical vs non-surgical trials in Cochrane reviews: a methodological study

Author instructions in biomedical journals infrequently address systematic review reporting and methodology: a cross-sectional study

OBJECTIVES

We aimed to analyze how instructions for authors in journals indexed in MEDLINE address systematic review (SR) reporting and methodology.

STUDY DESIGN AND SETTING

We analyzed instructions for authors in 20% of MEDLINE-indexed journals listed in the online catalog of the National Library of Medicine on July 27, 2021. We extracted data only from the instructions published in English. We extracted data on the existence of instructions for reporting and methodology of SRs.

RESULTS

Instructions from 1,237 journals mentioned SRs in 45% (n = 560) of the cases. Systematic review (SR) registration was mentioned in 104/1,237 (8%) of instructions. Guidelines for reporting SR protocols were found in 155/1,237 (13%) of instructions. Guidelines for reporting SRs were explicitly mentioned in 461/1,237 (37%), whereas the EQUATOR (Enhancing the Quality and Transparency of Health Research) network was referred to in 474/1,237 (38%) of instructions. Less than 2% (n = 20) of instructions mentioned risk of bias and meta-analyses; less than 1% mentioned certainty of evidence assessment, methodological expectations, updating of SRs, overviews of SRs, or scoping reviews.

CONCLUSION

Journals indexed in MEDLINE rarely provide instructions for authors regarding SR reporting and methodology. Such instructions could potentially raise authors' awareness and improve how SRs are prepared and reported.

Randomized Clinical Trials and Observational Tribulations: Providing Clinical Evidence for Personalized Surgical Pain Management Care Models

Proving clinical superiority of personalized care models in interventional and surgical pain management is challenging. The apparent difficulties may arise from the inability to standardize complex surgical procedures that often involve multiple steps. Ensuring the surgery is performed the same way every time is nearly impossible. Confounding factors, such as the variability of the patient population and selection bias regarding comorbidities and anatomical variations are also difficult to control for. Small sample sizes in study groups comparing iterations of a surgical protocol may amplify bias. It is essentially impossible to conceal the surgical treatment from the surgeon and the operating team. Restrictive inclusion and exclusion criteria may distort the study population to no longer reflect patients seen in daily practice. Hindsight bias is introduced by the inability to effectively blind patient group allocation, which affects clinical result interpretation, particularly if the outcome is already known to the investigators when the outcome analysis is performed (often a long time after the intervention). Randomization is equally problematic, as many patients want to avoid being randomly assigned to a study group, particularly if they perceive their surgeon to be unsure of which treatment will likely render the best clinical outcome for them. Ethical concerns may also exist if the study involves additional and unnecessary risks. Lastly, surgical trials are costly, especially if the tested interventions are complex and require long-term follow-up to assess their benefit. Traditional clinical testing of personalized surgical pain management treatments may be more challenging because individualized solutions tailored to each patient's pain generator can vary extensively. However, high-grade evidence is needed to prompt a protocol change and break with traditional image-based criteria for treatment. In this article, the authors review issues in surgical trials and offer practical solutions.

The clinical effectiveness and safety of intravenous unfractionated heparin following digital replantation and revascularization: A narrative systematic review

BACKGROUND

Digital replants and revascularization (DRV) have been performed since the 1960s but there are no recognized standard peri-operative anticoagulation practices. A narrative systematic review of the clinical effectiveness and safety of therapeutic peri-operative unfractionated heparin following DRV was undertaken.

METHODS

A review of the literature from 1985 to March 2022 was conducted using Medline, Embase, CINAHL and EBM reviews. Unfractionated heparin (UFH) use following DRV was compared to low-molecular weight heparin, other anticoagulants or no anticoagulation. Randomized trials, observational studies as well as guidelines were selected and independently screened. The Revised Cochrane risk-of-bias (RoB 2) tool and ROBINS-I were used to appraise risk of bias.

RESULTS

While the search strategy identified 1490 references, only six studies met the inclusion criteria. Significant heterogeneity and the low methodological quality of the evidence precluded a meta-analysis. Among the four studies that documented the surgical success rate associated with the use of a therapeutic dose of UFH post DRV, only two reported improved clinical outcomes. Evidence of a higher complication rate related to UFH use was found in four studies. Low quality evidence suggests that a therapeutic dose of unfractionated heparin leads to a higher risk of complications when compared with heparin given as an intermittent bolus of unfractionated heparin or subcutaneous heparin, or prostaglandin E1 or no heparin.

CONCLUSIONS

Current evidence suggests that IV UFH use following DRV has no significant impact on the success of the intervention. Heparin use may not be innocuous as some studies showed increased bleeding complications.

Efficacy and Safety of Immunosuppressant Therapy for Noninfectious Uveitis: A Systematic Review and Meta-Analysis

Objective

To analyze efficacy and safety of immunosuppressant therapy for noninfectious uveitis.

Methods

A network search of PubMed, ResearchGate, and EMBASE databases was conducted for relative literature and studies from the inception of each database to April 2021. Primary outcomes were efficacy and time to treatment failure of immunosuppressant for noninfectious uveitis. Secondary outcome was incidence of adverse events (AEs). Cochrane risk of bias tool was used to assess risk of bias of included studies. Fixed effects model or random effects model was implemented to assess statistical heterogeneity. Subgroup analysis was employed to analyze heterogeneous sources.

Results

Eight studies were deemed eligible for inclusion with a total of 848 patients. Six studies were randomized controlled trials (RCTs). Among them, a single-blind RCT had relatively high measurement bias and performance bias. Immunosuppressant presented favorable efficacy for noninfectious uveitis than placebo, and RR was 1.43 (95% CI: 1.12-1.82). Immunosuppressant for noninfectious uveitis prolonged the time before failure, and HR was 0.43 (95% CI: 0.32-0.54). AEs increased after immunosuppressant was applied. Compared with immunosuppressant, RR of AEs with placebo was 0.88 (95% CI: 0.71-1.08).

Conclusion

Immunosuppressant contributed to controlling progression of noninfectious uveitis to some extent. Compared with placebo, it increased incidence of AEs. More studies with low heterogeneity are warranted for stronger evidence in clinical.

Enhanced access to recommendations from the Cochrane Handbook for improving authors' judgments about risk of bias: A randomized controlled trial

This randomized controlled trial (RCT) aimed to test the efficacy of enhanced access to Cochrane Handbook (Handbook) recommendations for judging the 2011 Cochrane risk of bias (RoB) domains for improving the adequacy of RoB judgments. Parallel-group RCT with a 1:1 allocation ratio (N = 2271 per group) was conducted. Eligible participants were corresponding authors of all published Cochrane reviews and protocols. After allocation by a random number generator, participants received 20 scenarios for assessing RoB. The intervention group was shown tables from the Handbook with instructions for assessing 2011 RoB tool together with scenarios they were supposed to assess-enhanced access to the Handbook. The control group was shown only a general link to the Handbook. The primary outcome was the proportion of participants that made an adequate judgment of RoB scenarios for analyzed domains. There were 240 responses out of 2020 delivered e-mail invitations in the intervention and 197/2254 in the control group. Only five participants from the intervention group judged RoB adequately in all the 20 scenarios and no one in the control group. The proportion of participants who adequately assessed all the scenarios within a domain was significantly higher in the intervention than in the control group. The frequency of adequate RoB judgments was 7.1% (95% CI: 5.0-9.3%, p < 0.001) higher in the intervention group (76.2%) than in the control group (69.0%). The enhanced access yields more adequate RoB assessments and could be incorporated in software supporting the RoB tool.