The number of patients and events required to limit the risk of overestimation of intervention effects in meta-analysis--a simulation study

Major mistakes or errors in the use of trial sequential analysis in systematic reviews or meta-analyses - the METSA systematic review

BACKGROUND

Systematic reviews and data synthesis of randomised clinical trials play a crucial role in clinical practice, research, and health policy. Trial sequential analysis can be used in systematic reviews to control type I and type II errors, but methodological errors including lack of protocols and transparency are cause for concern. We assessed the reporting of trial sequential analysis.

METHODS

We searched Medline and the Cochrane Database of Systematic Reviews from 1 January 2018 to 31 December 2021 for systematic reviews and meta-analysis reports that include a trial sequential analysis. Only studies with at least two randomised clinical trials analysed in a forest plot and a trial sequential analysis were included. Two independent investigators assessed the studies. We evaluated protocolisation, reporting, and interpretation of the analyses, including their effect on any GRADE evaluation of imprecision.

RESULTS

We included 270 systematic reviews and 274 meta-analysis reports and extracted data from 624 trial sequential analyses. Only 134/270 (50%) systematic reviews planned the trial sequential analysis in the protocol. For analyses on dichotomous outcomes, the proportion of events in the control group was missing in 181/439 (41%), relative risk reduction in 105/439 (24%), alpha in 30/439 (7%), beta in 128/439 (29%), and heterogeneity in 232/439 (53%). For analyses on continuous outcomes, the minimally relevant difference was missing in 125/185 (68%), variance (or standard deviation) in 144/185 (78%), alpha in 23/185 (12%), beta in 63/185 (34%), and heterogeneity in 105/185 (57%). Graphical illustration of the trial sequential analysis was present in 93% of the analyses, however, the Z-curve was wrongly displayed in 135/624 (22%) and 227/624 (36%) did not include futility boundaries. The overall transparency of all 624 analyses was very poor in 236 (38%) and poor in 173 (28%).

CONCLUSIONS

The majority of trial sequential analyses are not transparent when preparing or presenting the required parameters, partly due to missing or poorly conducted protocols. This hampers interpretation, reproducibility, and validity.

STUDY REGISTRATION

PROSPERO CRD42021273811.

Tamoxifen for adults with hepatocellular carcinoma

RATIONALE

Hepatocellular carcinoma is the most common type of liver cancer, accounting for 70% to 85% of individuals with primary liver cancer. Tamoxifen has been evaluated in randomised clinical trials in people with hepatocellular cancer. The reported results have been inconsistent.

OBJECTIVES

To evaluate the benefits and harms of tamoxifen or tamoxifen plus any other anticancer drugs compared with no intervention, placebo, any type of standard care, or alternative treatment in adults with hepatocellular carcinoma, irrespective of sex, administered dose, type of formulation, and duration of treatment.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE, Embase, three other databases, and major trials registries, and handsearched reference lists up to 26 March 2024.

ELIGIBILITY CRITERIA

Parallel-group randomised clinical trials including adults (aged 18 years and above) diagnosed with advanced or unresectable hepatocellular carcinoma. Had we found cross-over trials, we would have included only the first trial phase. We did not consider data from quasi-randomised trials for analysis.

OUTCOMES

Our critical outcomes were all-cause mortality, serious adverse events, and health-related quality of life. Our important outcomes were disease progression, and adverse events considered non-serious.

RISK OF BIAS

We assessed risk of bias using the RoB 2 tool.

SYNTHESIS METHODS

We used standard Cochrane methods and Review Manager. We meta-analysed the outcome data at the longest follow-up. We presented the results of dichotomous outcomes as risk ratios (RR) and continuous data as mean difference (MD), with 95% confidence intervals (CI) using the random-effects model. We summarised the certainty of evidence using GRADE.

INCLUDED STUDIES

We included 10 trials that randomised 1715 participants with advanced, unresectable, or terminal stage hepatocellular carcinoma. Six were single-centre trials conducted in Hong Kong, Italy, and Spain, while three were conducted as multicentre trials in single countries (France, Italy, and Spain), and one trial was conducted in nine countries in the Asia-Pacific region (Australia, Hong Kong, Indonesia, Malaysia, Myanmar, New Zealand, Singapore, South Korea, and Thailand). The experimental intervention was tamoxifen in all trials. The control interventions were no intervention (three trials), placebo (six trials), and symptomatic treatment (one trial). Co-interventions were best supportive care (three trials) and standard care (one trial). The remaining six trials did not provide this information. The number of participants in the trials ranged from 22 to 496 (median 99), mean age was 63.7 (standard deviation 4.18) years, and mean proportion of men was 74.7% (standard deviation 42%). Follow-up was three months to five years.

SYNTHESIS OF RESULTS

Ten trials evaluated oral tamoxifen at five different dosages (ranging from 20 mg per day to 120 mg per day). All trials investigated one or more of our outcomes. We performed meta-analyses when at least two trials assessed similar types of tamoxifen versus similar control interventions. Eight trials evaluated all-cause mortality at varied follow-up points. Tamoxifen versus the control interventions (i.e. no treatment, placebo, and symptomatic treatment) results in little to no difference in mortality between one and five years (RR 0.99, 95% CI 0.92 to 1.06; 8 trials, 1364 participants; low-certainty evidence). In total, 488/682 (71.5%) participants died in the tamoxifen groups versus 487/682 (71.4%) in the control groups. The separate analysis results for one, between two and three, and five years were comparable to the analysis result for all follow-up periods taken together. The evidence is very uncertain about the effect of tamoxifen versus no treatment on serious adverse events at one-year follow-up (RR 0.44, 95% CI 0.19 to 1.06; 1 trial, 36 participants; very low-certainty evidence). A total of 5/20 (25.0%) participants in the tamoxifen group versus 9/16 (56.3%) participants in the control group experienced serious adverse events. One trial measured health-related quality of life at baseline and at nine months' follow-up, using the Spitzer Quality of Life Index. The evidence is very uncertain about the effect of tamoxifen versus no treatment on health-related quality of life (MD 0.03, 95% CI -0.45 to 0.51; 1 trial, 420 participants; very low-certainty evidence). A second trial found no appreciable difference in global health-related quality of life scores. No further data were provided. Tamoxifen versus control interventions (i.e. no treatment, placebo, or symptomatic treatment) results in little to no difference in disease progression between one and five years' follow-up (RR 1.02, 95% CI 0.91 to 1.14; 4 trials, 720 participants; low-certainty evidence). A total of 191/358 (53.3%) participants in the tamoxifen group versus 198/362 (54.7%) participants in the control group had progression of hepatocellular carcinoma. Tamoxifen versus control interventions (i.e. no treatment or placebo) may have little to no effect on adverse events considered non-serious during treatment, but the evidence is very uncertain (RR 1.17, 95% CI 0.45 to 3.06; 4 trials, 462 participants; very low-certainty evidence). A total of 10/265 (3.8%) participants in the tamoxifen group versus 6/197 (3.0%) participants in the control group had adverse events considered non-serious. We identified no trials with participants diagnosed with early stages of hepatocellular carcinoma. We identified no ongoing trials.

AUTHORS' CONCLUSIONS

Based on the low- and very low-certainty evidence, the effects of tamoxifen on all-cause mortality, disease progression, serious adverse events, health-related quality of life, and adverse events considered non-serious in adults with advanced, unresectable, or terminal stage hepatocellular carcinoma when compared with no intervention, placebo, or symptomatic treatment could not be established. Our findings are mostly based on trials at high risk of bias with insufficient power (fewer than 100 participants), and a lack of trial data on clinically important outcomes. Therefore, firm conclusions cannot be drawn. Trials comparing tamoxifen administered with any other anticancer drug versus standard care, usual care, or alternative treatment as control interventions were lacking. Evidence on the benefits and harms of tamoxifen in participants at the early stages of hepatocellular carcinoma was also lacking.

FUNDING

This Cochrane review had no dedicated funding.

REGISTRATION

Protocol available via DOI: 10.1002/14651858.CD014869.

Effects of primary or secondary prevention with vitamin A supplementation on clinically important outcomes: a systematic review of randomised clinical trials with meta-analysis and trial sequential analysis

OBJECTIVES

This systematic review with meta-analyses of randomised trials evaluated the preventive effects of vitamin A supplements versus placebo or no intervention on clinically important outcomes, in people of any age.

METHODS

We searched different electronic databases and other resources for randomised clinical trials that had compared vitamin A supplements versus placebo or no intervention (last search 16 April 2024). We used Cochrane methodology. We used the random-effects model to calculate risk ratios (RRs), with 95% CIs. We analysed individually and cluster randomised trials separately. Our primary outcomes were mortality, adverse events and quality of life. We assessed risks of bias in the trials and used Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) to assess the certainty of the evidence.

RESULTS

We included 120 randomised trials (1 671 672 participants); 105 trials allocated individuals and 15 allocated clusters. 92 trials included children (78 individually; 14 cluster randomised) and 28 adults (27 individually; 1 cluster randomised). 14/105 individually randomised trials (13%) and none of the cluster randomised trials were at overall low risk of bias. Vitamin A did not reduce mortality in individually randomised trials (RR 0.99, 95% CI 0.93 to 1.05; I²=32%; p=0.19; 105 trials; moderate certainty), and this effect was not affected by the risk of bias. In individually randomised trials, vitamin A had no effect on mortality in children (RR 0.96, 95% CI 0.88 to 1.04; I²=24%; p=0.28; 78 trials, 178 094 participants) nor in adults (RR 1.04, 95% CI 0.97 to 1.13; I²=24%; p=0.27; 27 trials, 61 880 participants). Vitamin A reduced mortality in the cluster randomised trials (0.84, 95% CI 0.76 to 0.93; I²=66%; p=0.0008; 15 trials, 14 in children and 1 in adults; 364 343 participants; very low certainty). No trial reported serious adverse events or quality of life. Vitamin A slightly increased bulging fontanelle of neonates and infants. We are uncertain whether vitamin A influences blindness under the conditions examined.

CONCLUSIONS

Based on moderate certainty of evidence, vitamin A had no effect on mortality in the individually randomised trials. Very low certainty evidence obtained from cluster randomised trials suggested a beneficial effect of vitamin A on mortality. If preventive vitamin A programmes are to be continued, supporting evidence should come from randomised trials allocating individuals and assessing patient-meaningful outcomes.

PROSPERO REGISTRATION NUMBER

CRD42018104347.

Epidemiology of musculoskeletal injury in professional and amateur golfers: a systematic review and meta-analysis

OBJECTIVE

To determine the prevalence and incidence of musculoskeletal injury in amateur and professional golfers, and to identify common injury sites and factors associated with increased injury frequency.

DESIGN

Systematic epidemiological review and meta-analysis.

DATA SOURCES

PubMed (Medline), Embase, the Cochrane Library and SPORTDiscus were searched in September 2023.

ELIGIBILITY CRITERIA

Studies published in the English language reporting the incidence or prevalence of musculoskeletal injuries in golfers at all anatomical sites.

RESULTS

20 studies (9221 golfers, 71.9% male, 28.1% female) were included, with mean age 46.8 years. Lifetime injury prevalence was significantly greater in professional golfers (73.5% (95% CI: 47.3% to 93.0%)) than amateur golfers (56.6% (95% CI: 47.4% to 65.5%); relative risk (RR)=1.50, p<0.001). Professional golfers had a significantly greater lifetime prevalence of hand and wrist (RR=3.33, p<0.001) and lower back injury (RR=3.05, p<0.001). Soft tissue injuries were most common, and diagnoses were typically non-specific. Injury frequency was not associated with age or sex. Two studies reported a greater injury risk in amateur golfers playing more than three and four rounds per week.

CONCLUSION

Over half of golfers are at risk of sustaining a musculoskeletal injury during their lifetime. Risks and patterns of injury differ between professional and amateur golfers, with professionals significantly more likely to develop lower back, and hand and wrist injuries. A recent international consensus statement on the reporting of injury and illness in golf should aid consistency in future research assessing the epidemiology of specific diagnoses, informing golf injury prevention and management strategies.

PROSPERO REGISTRATION NUMBER

CRD42023408738.

Trial sequential analysis: A simple guide for judging the conclusiveness of the effect

Meta-analysis is a statistical method used in systematic reviews to provide a quantitative estimate of the effect. However, including very few studies and participants may increase the risk of spurious findings. Trial sequential analysis (TSA) has been introduced to enhance the robustness of meta-analysis. TSA is a cumulative meta-analysis method that weighs type I and II errors while estimating the effect. The application of TSA can lead to a more accurate estimation of the clinical effectiveness of the intervention. The aim of the present paper was to introduce the TSA to orthodontic clinicians and researchers using continuous data from an orthodontic systematic review.

Intracoronary Thrombolysis in ST-Segment Elevation Myocardial Infarction Patients Undergoing Primary Percutaneous Coronary Intervention: an Updated Meta-analysis of Randomized Controlled Trials

BACKGROUND

Primary percutaneous coronary intervention (PPCI) is the standard reperfusion treatment in ST-segment elevation myocardial infarction (STEMI). Intracoronary thrombolysis (ICT) may reduce thrombotic burden in the infarct-related artery, which is often responsible for microvascular obstruction and no-reflow.

METHODS

We conducted, according to the PRISMA statement, the largest meta-analysis to date of ICT as adjuvant therapy to PPCI. All relevant studies were identified by searching the PubMed, Scopus, Cochrane Library, and Web of Science.

RESULTS

Thirteen randomized controlled trials (RCTs) involving a total of 1876 patients were included. Compared to the control group, STEMI ICT-treated patients had fewer major adverse cardiac events (MACE) (OR 0.65, 95% CI, 0.48-0.86, P = 0.003) and an improved 6-month left ventricular ejection fraction (MD 3.78, 95% CI, 1.53-6.02, P = 0.0010). Indices of enhanced myocardial microcirculation were better with ICT (Post-PCI corrected thrombolysis in myocardial infarction (TIMI) frame count (MD - 3.57; 95% CI, - 5.00 to - 2.14, P < 0.00001); myocardial blush grade (MBG) 2/3 (OR 1.76; 95% CI, 1.16-2.69, P = 0.008), and complete ST-segment resolution (OR 1.97; 95% CI, 1.33-2.91, P = 0.0007)). The odds for major bleeding were comparable between the 2 groups (OR 1.27; 95% CI, 0.61-2.63, P = 0.53).

CONCLUSIONS

The present meta-analysis suggests that ICT was associated with improved MACE and myocardial microcirculation in STEMI patients undergoing PPCI, without significant increase in major bleeding. However, these findings necessitate confirmation in a contemporary large RCT.

Mindfulness-based interventions for preadolescent children: A comprehensive meta-analysis

Among the many social and emotional learning (SEL) interventions available, mindfulness-based interventions (MBIs) have become increasingly popular, particularly for preadolescent children who were once thought to not possess the metacognitive abilities or cognitive resources to benefit from such training. Although previous research syntheses indicate that MBIs show promise in promoting positive outcomes across a range of domains, the effectiveness of MBIs for preadolescent children may be masked by the effects of older children who have comprised the majority of samples in past meta-analyses. Hence, to better understand the impact of mindfulness-based training on preadolescent children (ages 6-12 years), the present study reviewed treatment effect estimates across a range of outcomes, including mindfulness, attention, metacognition and cognitive flexibility, emotional and behavioral regulation, academic achievement and school functioning, positive emotion and self-appraisal, negative emotion and subjective distress, externalizing problems, internalizing problems, social competence and prosocial behavior, and physical health. Thirty-two studies (nparticipants = 3640) were identified and included in a random-effects meta-analyses. The results from multiple meta-analytical analyses conducted in the present study suggest that preadolescents have experienced significant benefits across attention, emotional and behavioral regulation, positive emotion and self-appraisal, and social competence and prosocial behavior (g = 0.19 to 0.39). However, the overall effect was deemed small (g = 0.34). Due to the lack of comparison studies with SEL interventions, it remains unclear whether MBIs are as effective as traditional approaches in promoting healthy development and academic achievement for preadolescent children. Additionally, results from the present meta-analysis suggest various recommendations for future studies to ensure a continued growth in understanding how MBIs can be used with children.

The Fragility of Landmark Randomized Controlled Trials in the Plastic Surgery Literature

Background

Randomized controlled trials (RCTs) are integral to the progress of evidenced-based medicine and help guide changes in the standards of care. Although results are traditionally evaluated according to their corresponding P value, the universal utility of this statistical metric has been called into question. The fragility index (FI) has been developed as an adjunct method to provide additional statistical perspective. In this study, we aimed to determine the fragility of 25 highly cited RCTs in the plastic surgery literature.

Methods

A PubMed search was used to identify the 25 highest cited RCTs with statistically significant dichotomous outcomes across 24 plastic surgery journals. Article characteristics were extracted, and the FI of each article was calculated. Additionally, Altmetric scores were determined for each study to determine article attention across internet platforms.

Results

The median FI score across included studies was 4 (2-7.5, interquartile range). The two highest FI scores were 208 and 58, respectively. Four studies (16%) had scores of 0 or 1. Three studies (12%) had scores of 2. All other studies (72%) had FI scores of 3 or higher. The median Altmetric score was 0 (0-3).

Conclusion

The FI can provide additional perspective on the robustness of study results, but like the P value, it should be interpreted in the greater context of other study elements.

Deep Neuromuscular Block for Endolaryngeal Surgery: A Systematic Review and Meta-Analysis

OBJECTIVES

To determine the safety and efficacy of deep neuromuscular block (NMB) for endolaryngeal surgery.

DATA SOURCES

PubMed, Web of Science, Cochrane Library, Ovid Medline, Embase, China National Knowledge Infrastructure, Wanfang, VIP databases, and trial registry database.

METHODS

Inclusion criteria followed the PICOS principles: Participants, adults undergoing endolaryngeal surgery; Intervention, deep NMB performed during the surgery; Control, no-deep NMB performed; Outcomes, primary outcome: the incidence of clinically acceptable surgical conditions.

SECONDARY OUTCOME

the incidence of intraoperative complications (including vocal fold movement and coughing) and total incidence of postoperative complications [including postoperative residual curarization (PORC), postoperative sore throat (POST), and postoperative nausea and vomiting (PONV)]. Study design, randomized controlled trials (RCTs). Duplicate publications, editorials, letters, abstracts, and reviews were excluded.

RESULTS

Four articles with 242 patients were identified for analysis. The results indicated that compared with no-deep NMB, deep NMB provides a higher incidence of clinically acceptable surgical conditions (98.36% vs. 76.67%; relative ratio [RR] = 1.29, 95% CI: 1.07-1.56), a lower incidence of intraoperative complications (10.83% versus 37.16%; RR = 0.32; 95% CI: 0.21-0.49) (lower incidence of vocal fold movement [1.85% vs. 34%; RR = 0.08, 95% CI: 0.02-0.41] and coughing [15.53% vs. 38.78%; RR = 0.42, 95% CI: 0.27-0.66]). There were no differences in the overall incidence of postoperative complications (RR = 2.10, 95% CI: 0.12-36.40).

CONCLUSIONS

Based on current published evidence, deep NMB provides better surgical conditions with a higher incidence of clinically acceptable surgical conditions and a lower incidence of intraoperative complications (lower incidence of vocal fold movement and coughing) without increasing the overall incidence of postoperative complications.

LEVEL OF EVIDENCE

1 Laryngoscope, 133:2055-2065, 2023.

A fragility index analysis of clinical trials evaluating low-intensity extracorporeal shockwave therapy for erectile dysfunction

Erectile dysfunction is a common sexual dysfunction that affects a significant proportion of men. Low-intensity extracorporeal shockwave therapy has been evaluated in multiple clinical trials as a therapeutic option for men with erectile dysfunction. The robustness of these clinical trials is not well defined, as the trials are hindered by inconsistent treatment protocols, small study arm size and short follow-up intervals. The fragility index is a statistical analysis which is used to evaluate the robustness of clinical trials. It is calculated by evaluating the minimum number of patients in a given trial arm that would be required to have an alternative outcome to alter the statistical significance of the results. The lowest fragility index in statistically significant trials is 1, meaning that if just one participant experienced an alternate outcome, the results would no longer achieve statistical significance. The upper limit is determined by the number of participants in a given arm of the trial. Herein, a scoping review of clinical trials evaluating the efficacy of low-intensity extracorporeal shockwave therapy in erectile dysfunction to determine the fragility index of trials with clinically significant results. We hypothesized that the fragility index would be low, indicating the results are less robust and generalizable.

A guide to appropriately planning and conducting meta-analyses-Part 1: indications, assumptions and understanding risk of bias

A meta-analysis is the quantitative synthesis of data from two or more individual studies and are as a rule an important method of obtaining a more accurate estimate of the direction and magnitude of a treatment effect. However, it is imperative that the meta-analysis be performed with proper, rigorous methodology to ensure validity of the results and their interpretation. In this article the authors will review the most important questions researchers should consider when planning a meta-analysis to ensure proper indications and methodologies, minimize the risk of bias, and avoid misleading conclusions.

Robustness of Significant Dichotomous Outcomes in Randomized Controlled Trials in the Treatment of Patients with COVID-19: A Systematic Analysis

Purpose

Significant results of randomized controlled trials (RCTs) should be properly weighed. This study adopted fragility index (FI) to evaluate the robustness of significant dichotomous outcomes from RCTs on coronavirus disease 2019 (COVID-19) treatment.

Materials and methods

ClinicalTrials.gov and PubMed were searched from inception to July 31, 2021. FIs were calculated and their distribution was depicted. FI's categorical influential factors were analyzed. Spearman correlation coefficient (r _s) was reported for the relationship between FI and the continuous characteristics of RCTs.

Results

Fifty RCTs with 120 outcomes in 7869 patients were included. The FI distribution was abnormal with median 3 (interquartile range 1-7, P = 0.0001). The FIs and robustness were affected by the outcomes of interest, various patient populations, and interventions (T = 18.215,16.667, 23.107; P = 0.02,0.0001, 0.001, respectively). A cubic relationship between the FIs and absolute difference of events between groups with R square of 0.848 (T = 215.828, P = 0.0001, R square = 0.865) was observed. A strong negative logarithmic relationship existed between FI and the P value with R square = - 0.834.

Conclusion

The robustness of significant dichotomous outcomes of COVID-19 treatments was fragile and affected by the outcomes of interest, patients, interventions, P value, and absolute difference of events between the groups. FI was an useful quantitative metric for the binary significant outcomes on COVID-19 treatments.

Registration

PROSPERO (CRD42021272455).

Supplementary Information

The online version contains supplementary material available at 10.1007/s44231-022-00027-y.

Control interventions in randomised trials among people with mental health disorders

BACKGROUND

Control interventions in randomised trials provide a frame of reference for the experimental interventions and enable estimations of causality. In the case of randomised trials assessing patients with mental health disorders, many different control interventions are used, and the choice of control intervention may have considerable impact on the estimated effects of the treatments being evaluated.

OBJECTIVES

To assess the benefits and harms of typical control interventions in randomised trials with patients with mental health disorders. The difference in effects between control interventions translates directly to the impact a control group has on the estimated effect of an experimental intervention. We aimed primarily to assess the difference in effects between (i) wait-list versus no-treatment, (ii) usual care versus wait-list or no-treatment, and (iii) placebo interventions (all placebo interventions combined or psychological, pharmacological, and physical placebos individually) versus wait-list or no-treatment. Wait-list patients are offered the experimental intervention by the researchers after the trial has been finalised if it offers more benefits than harms, while no-treatment participants are not offered the experimental intervention by the researchers.

SEARCH METHODS

In March 2018, we searched MEDLINE, PsycInfo, Embase, CENTRAL, and seven other databases and six trials registers.

SELECTION CRITERIA

We included randomised trials assessing patients with a mental health disorder that compared wait-list, usual care, or placebo interventions with wait-list or no-treatment .

DATA COLLECTION AND ANALYSIS

Titles, abstracts, and full texts were reviewed for eligibility. Review authors independently extracted data and assessed risk of bias using Cochrane's risk of bias tool. GRADE was used to assess the quality of the evidence. We contacted researchers working in the field to ask for data from additional published and unpublished trials. A pre-planned decision hierarchy was used to select one benefit and one harm outcome from each trial. For the assessment of benefits, we summarised continuous data as standardised mean differences (SMDs) and dichotomous data as risk ratios (RRs). We used risk differences (RDs) for the assessment of adverse events. We used random-effects models for all statistical analyses. We used subgroup analysis to explore potential causes for heterogeneity (e.g. type of placebo) and sensitivity analyses to explore the robustness of the primary analyses (e.g. fixed-effect model).

MAIN RESULTS

We included 96 randomised trials (4200 participants), ranging from 8 to 393 participants in each trial. 83 trials (3614 participants) provided usable data. The trials included 15 different mental health disorders, the most common being anxiety (25 trials), depression (16 trials), and sleep-wake disorders (11 trials). All 96 trials were assessed as high risk of bias partly because of the inability to blind participants and personnel in trials with two control interventions. The quality of evidence was rated low to very low, mostly due to risk of bias, imprecision in estimates, and heterogeneity. Only one trial compared wait-list versus no-treatment directly but the authors were not able to provide us with any usable data on the comparison. Five trials compared usual care versus wait-list or no-treatment and found a SMD -0.33 (95% CI -0.83 to 0.16, I² = 86%, 523 participants) on benefits. The difference between all placebo interventions combined versus wait-list or no-treatment was SMD -0.37 (95% CI -0.49 to -0.25, I² = 41%, 65 trials, 2446 participants) on benefits. There was evidence of some asymmetry in the funnel plot (Egger's test P value of 0.087). Almost all the trials were small. Subgroup analysis found a moderate effect in favour of psychological placebos SMD -0.49 (95% CI -0.64 to -0.30; I² = 53%, 39 trials, 1656 participants). The effect of pharmacological placebos versus wait-list or no-treatment on benefits was SMD -0.14 (95% CI -0.39 to 0.11, 9 trials, 279 participants) and the effect of physical placebos was SMD -0.21 (95% CI -0.35 to -0.08, I² = 0%, 17 trials, 896 participants). We found large variations in effect sizes in the psychological and pharmacological placebo comparisons. For specific mental health disorders, we found significant differences in favour of all placebos for sleep-wake disorders, major depressive disorder, and anxiety disorders, but the analyses were imprecise due to sparse data. We found no significant differences in harms for any of the comparisons but the analyses suffered from sparse data. When using a fixed-effect model in a sensitivity analysis on the comparison for usual care versus wait-list and no-treatment, the results were significant with an SMD of -0.46 (95 % CI -0.64 to -0.28). We reported an alternative risk of bias model where we excluded the blinding domains seeing how issues with blinding may be seen as part of the review investigation itself. However, this did not markedly change the overall risk of bias profile as most of the trials still included one or more unclear bias domains.

AUTHORS' CONCLUSIONS

We found marked variations in effects between placebo versus no-treatment and wait-list and between subtypes of placebo with the same comparisons. Almost all the trials were small with considerable methodological and clinical variability in factors such as mental health population, contents of the included control interventions, and outcome domains. All trials were assessed as high risk of bias and the evidence quality was low to very low. When researchers decide to use placebos or usual care control interventions in trials with people with mental health disorders it will often lead to lower estimated effects of the experimental intervention than when using wait-list or no-treatment controls. The choice of a control intervention therefore has considerable impact on how effective a mental health treatment appears to be. Methodological guideline development is needed to reach a consensus on future standards for the design and reporting of control interventions in mental health intervention research.

MRI volumetric changes in hippocampal subfields in psychosis: a protocol for a systematic review and meta-analysis

BACKGROUND

The hippocampus has for long been known for its ability to form new, declarative memory. However, emerging findings across conditions in the psychosis spectrum also implicate its role in emotional regulation. Systematic reviews have demonstrated consistent volume atrophic changes in the hippocampus. The aim of the systematic review and metanalysis which will follow from this protocol will be to investigate the volume-based neuroimaging findings across each of the subfields of the hippocampus in psychosis independent of diagnosis.

METHODS

Volume changes across subfields of the hippocampus in psychotic illnesses will be assessed by systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). MRI neuroimaging studies of patients with a definitive diagnosis of psychosis (including brief pre-diagnostic states) will be included. Studies lacking adequate controls, illicit drug use, medical psychosis, history of other significant psychiatric comorbidities, or emphasis on age groups above 65 or below 16 will be excluded. Subfields investigated will include the CA1, CA2/3, CA4, subiculum, presubiculum, parasubiculum, dentate gyrus, stratum, molecular layer, granular cell layer, entorhinal cortex, and fimbria. Two people will independently screen abstracts from the output of the search to select suitable studies. This will be followed by the two reviewers performing a full-text review of the studies which were selected based on suitable abstracts. One reviewer will independently perform all the data extraction, and another reviewer will then systemically check all the extracted information using the original articles to ensure accuracy. Statistical analysis will be performed using the metafor and meta-packages in R Studio with the application of the random-effects model.

DISCUSSION

This study will provide insight into the volumetric changes in psychosis of the subfields of the hippocampus, independent of diagnosis. This may shed light on the intricate neural pathology which encompasses psychosis and will open avenues for further exploration of the structures identified as potential drivers of volume change.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020199558.

Associations between anger and chronic primary pain: a systematic review and meta-analysis

OBJECTIVES

Anger is a negative emotion characterized by antagonism toward someone or something, is rooted in an appraisal or attribution of wrongdoing, and is accompanied by an action tendency to undo the wrongdoing. Anger is prevalent in individuals with chronic pain, especially those with chronic primary pain. The associations between anger and pain-related outcomes (e.g., pain intensity, disability) have been examined in previous studies. However, to our knowledge, no systematic review or meta-analysis has summarized the findings of anger-pain associations through a focus on chronic primary pain. Hence, we sought to summarize the findings on the associations of anger-related variables with pain and disability in individuals with chronic primary pain.

METHODS

All studies reporting at least one association between anger-related variables and the two pain-related outcomes in individuals with chronic primary pain were eligible. We searched electronic databases using keywords relevant to anger and chronic primary pain. Multiple reviewers independently screened for study eligibility, data extraction, and methodological quality assessment.

RESULTS

Thirty-eight studies were included in this systematic review, of which 20 provided data for meta-analyses (2,682 participants with chronic primary pain). Of the included studies, 68.4% had a medium methodological quality. Evidence showed mixed results in the qualitative synthesis. Most anger-related variables had significant positive pooled correlations with small to moderate effect sizes for pain and disability.

CONCLUSIONS

Through a comprehensive search, we identified several key anger-related variables associated with pain-related outcomes. In particular, associations with perceived injustice were substantial.

Using the Barthel Index and modified Rankin Scale as Outcome Measures for Stroke Rehabilitation Trials; A Comparison of Minimum Sample Size Requirements

OBJECTIVES

Underpowered trials risk inaccurate results. Recruitment to stroke rehabilitation randomised controlled trials (RCTs) is often a challenge. Statistical simulations offer an important opportunity to explore the adequacy of sample sizes in the context of specific outcome measures. We aimed to examine and compare the adequacy of stroke rehabilitation RCT sample sizes using the Barthel Index (BI) or modified Rankin Scale (mRS) as primary outcomes.

METHODS

We conducted computer simulations using typical experimental event rates (EER) and control event rates (CER) based on individual participant data (IPD) from stroke rehabilitation RCTs. Event rates are the proportion of participants who experienced clinically relevant improvements in the RCT experimental and control groups. We examined minimum sample size requirements and estimated the number of participants required to achieve a number needed to treat within clinically acceptable boundaries for the BI and mRS.

RESULTS

We secured 2350 IPD (18 RCTs). For a 90% chance of statistical accuracy on the BI a rehabilitation RCT would require 273 participants per randomised group. Accurate interpretation of effect sizes would require 1000s of participants per group. Simulations for the mRS were not possible as a clinically relevant improvement was not detected when using this outcome measure.

CONCLUSIONS

Stroke rehabilitation RCTs with large sample sizes are required for accurate interpretation of effect sizes based on the BI. The mRS lacked sensitivity to detect change and thus may be unsuitable as a primary outcome in stroke rehabilitation trials.

EEG-connectivity: A fundamental guide and checklist for optimal study design and evaluation

Brain connectivity can be estimated through many analyses applied to electroencephalographic (EEG) data. However, substantial heterogeneity in the implementation of connectivity methods exist. Heterogeneity in conceptualization of connectivity measures, data collection, or data pre-processing may be associated with variability in robustness of measurement. While it is difficult to compare the results of studies using different EEG connectivity measures, standardization of processing and reporting may facilitate the task. We discuss how factors such as referencing, epoch length and number, controls for volume conduction, artefact removal, and statistical control of multiple comparisons influence the EEG connectivity estimate for connectivity measures, and what can be done to control for potential confounds associated with these factors. Based on the results reported in previous literature, this article presents recommendations and a novel checklist developed for quality assessment of EEG connectivity studies. This checklist and its recommendations are made in an effort to draw attention to factors that may influence connectivity estimates and factors that need to be improved in future research. Standardization of procedures and reporting in EEG connectivity may lead to EEG connectivity studies to be made more synthesisable and comparable despite variations in the methodology underlying connectivity estimates.

Efficacy and safety of hydroxychloroquine as pre-and post-exposure prophylaxis and treatment of COVID-19: A systematic review and meta-analysis of blinded, placebo-controlled, randomized clinical trials

BACKGROUND

Hydroxychloroquine (HCQ) is an anti-malarial and immunomodulatory drug considered a potential candidate for drug repurposing in COVID-19 due to their in vitro antiviral activity against SARS-CoV-2. Despite the potential antiviral effects and anti-inflammatory profile, the results based on clinical studies are contradictory. Therefore, the quality of the decision-making process from meta-analyses summarizing the available evidence selecting studies with different designs and unblinded trials is limited. The aim of this study was to synthesize the best evidence on the efficacy and safety of HCQ as pre-and post-exposure prophylaxis and treatment of non-hospitalized and hospitalized patients with COVID-19.

METHODS

Searches were performed in PubMed, Web of Science, Embase, Lilacs, the website ClinicalTrials.gov and the preprint server medRxiv from January 1, 2020 to May 17, 2021. The following elements were used to define eligibility criteria: (1) Population: individuals at high-risk of exposure to SARS-CoV-2 (pre-exposure), individuals who had close contact with a positive or probable case of COVID-19 (post-exposure), non-hospitalized patients with COVID-19 and hospitalized patients with COVID-19; (2) Intervention: HCQ; (3) Comparison: placebo; (4) Outcomes: incidence of SARS-CoV-2 infection, need for hospitalization, length of hospital stay, need for invasive mechanical ventilation (MV), death, and adverse events; and (5) Study type: blinded, placebo-controlled, randomized clinical trials (RCTs). Risk of bias was judged according to the Cochrane guidelines for RCTs. Treatment effects were reported as relative risk (RR) for dichotomous variables and mean difference (MD) for continuous variables with 95% confidence intervals (CI). We used either a fixed or random-effects model to pool the results of individual studies depending on the presence of heterogeneity. The GRADE system was used to evaluate the strength of evidence between use of HCQ and the outcomes of interest.

FINDINGS

Fourteen blinded, placebo-controlled RCTs were included in this meta-analysis. Four trials (1942 patients: HCQ = 1271; placebo = 671) used HCQ as a prophylactic medication pre-exposure to COVID-19, two (1650 patients: HCQ = 821; placebo = 829) as a prophylactic medication post-exposure to COVID-19, three (1018 patients: HCQ = 497; placebo = 521) as treatment for non-hospitalized patients, and five (1138 patients: HCQ = 572; placebo = 566) as treatment for hospitalized patients with COVID-19. We found no decreased risk of SARS-CoV-2 infection among individuals receiving HCQ as pre-exposure (RR = 0.90; 95% CI 0.46 to 1.77) or post-exposure (RR = 0.96; 95% CI 0.72 to 1.29) prophylaxis to prevent COVID-19. There was no significant decreased risk of hospitalization for outpatients with SARS-CoV-2 infection (RR = 0.64; 95% CI 0.33 to 1.23) and no decreased risk of MV (RR = 0.81; 95% CI 0.49 to 1.34) and death (RR = 1.05; 95% CI 0.62 to 1.78) among hospitalized patients with COVID-19 receiving HCQ. The certainty of the results on the lack of clinical benefit for HCQ was rated as moderate. Moreover, our results demonstrated an increased risk for any adverse events and gastrointestinal symptoms among those using HCQ.

INTERPRETATION

Available evidence based on the results of blinded, placebo-controlled RCTs showed no clinical benefits of HCQ as pre-and post-exposure prophylaxis and treatment of non-hospitalized and hospitalized patients with COVID-19.

FUNDING

There was no funding source.

Prevalence of depression in women with low income living in developed countries

OBJECTIVE

To conduct a systematic review of studies reporting prevalence rates of depression in women living in low-income circumstances in developed countries.

METHODS

The published and unpublished literature was searched for studies reporting prevalence of depression in women with low income in developed countries. Searches, data extraction, and methodological appraisal were conducted twice independently. To perform the analysis, the meta and metafor packages in R, a random effect model to account for both between and within studies' variances, and the restricted maximum likelihood method for estimation were used.

RESULTS

One-hundred sixty-four studies, involving 218,035 participants, were located through the search process. The point prevalence of depression among women in low-income circumstances using self-report instruments in 134 studies was 37.4% (95% CI, 34.0%-40.7%). Additionally, the point prevalence according to depression diagnosis in 25 studies was 22.9% (95% CI, 17.8%-28.5%).

CONCLUSIONS

The high rate of depression among women living in low-income circumstances is of serious public health concern.

POLICY IMPLICATIONS

Women living in low-income circumstances should receive screening and referral/treatment in not only medical service settings, but also in social service settings serving women receiving welfare benefits.

Vitamin D supplementation for chronic liver diseases in adults

BACKGROUND

Vitamin D deficiency is often reported in people with chronic liver diseases. Improving vitamin D status could therefore be beneficial for people with chronic liver diseases.

OBJECTIVES

To assess the beneficial and harmful effects of vitamin D supplementation in adults with chronic liver diseases.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE Ovid, Embase Ovid, LILACS, Science Citation Index Expanded, and Conference Proceedings Citation Index-Science. We also searched ClinicalTrials.gov  and the World Health Organization International Clinical Trials Registry Platform. We scanned bibliographies of relevant publications and enquired experts and pharmaceutical companies as to additional trials. All searches were up to November 2020.

SELECTION CRITERIA

Randomised clinical trials that compared vitamin D at any dose, duration, and route of administration versus placebo or no intervention in adults with chronic liver diseases. Vitamin D could have been administered as supplemental vitamin D (vitamin D₃ (cholecalciferol) or vitamin D₂ (ergocalciferol)), or an active form of vitamin D (1α-hydroxyvitamin D (alfacalcidol), 25-hydroxyvitamin D (calcidiol), or 1,25-dihydroxyvitamin D (calcitriol)).

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We used GRADE to assess the certainty of evidence.

MAIN RESULTS

We included 27 randomised clinical trials with 1979 adult participants. This review update added 12 trials with 945 participants. We assessed all trials as at high risk of bias. All trials had a parallel-group design. Eleven trials were conducted in high-income countries and 16 trials in middle-income countries. Ten trials included participants with chronic hepatitis C, five trials participants with liver cirrhosis, 11 trials participants with non-alcoholic fatty liver disease, and one trial liver transplant recipients. All of the included trials reported the baseline vitamin D status of participants. Participants in nine trials had baseline serum 25-hydroxyvitamin D levels at or above vitamin D adequacy (20 ng/mL), whilst participants in the remaining 18 trials were vitamin D insufficient (less than 20 ng/mL). Twenty-four trials administered vitamin D orally, two trials intramuscularly, and one trial intramuscularly and orally. In all 27 trials, the mean duration of vitamin D supplementation was 6 months, and the mean follow-up of participants from randomisation was 7 months. Twenty trials (1592 participants; 44% women; mean age 48 years) tested vitamin D₃ (cholecalciferol); three trials (156 participants; 28% women; mean age 54 years) tested vitamin D₂; four trials (291 participants; 60% women; mean age 52 years) tested 1,25-dihydroxyvitamin D; and one trial (18 participants; 0% women; mean age 52 years) tested 25-hydroxyvitamin D. One trial did not report the form of vitamin D. Twelve trials used a placebo, whilst the other 15 trials used no intervention in the control group. Fourteen trials appeared to be free of vested interest. Eleven trials did not provide any information on clinical trial support or sponsorship. Two trials were funded by industry. We are very uncertain regarding the effect of vitamin D versus placebo or no intervention on all-cause mortality (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.51 to 1.45; 27 trials; 1979 participants). The mean follow-up was 7 months (range 1 to 18 months). We are very uncertain regarding the effect of vitamin D versus placebo or no intervention on liver-related mortality (RR 1.62, 95% CI 0.08 to 34.66; 1 trial; 18 participants) (follow-up: 12 months); serious adverse events such as hypercalcaemia (RR 5.00, 95% CI 0.25 to 100.8; 1 trial; 76 participants); myocardial infarction (RR 0.75, 95% CI 0.08 to 6.81; 2 trials; 86 participants); thyroiditis (RR 0.33, 95% CI 0.01 to 7.91; 1 trial; 68 participants); circular haemorrhoidal prolapse (RR 3.00, 95% CI 0.14 to 65.9; 1 trial; 20 participants); bronchopneumonia (RR 0.33, 95% CI 0.02 to 7.32; 1 trial 20 participants); and non-serious adverse events. The certainty of evidence for all outcomes is very low. We found no data on liver-related morbidity such as gastrointestinal bleeding, hepatic encephalopathy, hepatorenal syndrome, ascites, or liver cancer. There were also no data on health-related quality of life. The evidence is also very uncertain regarding the effect of vitamin D versus placebo or no intervention on rapid, early, and sustained virological response in people with chronic hepatitis C.

AUTHORS' CONCLUSIONS

Given the high risk of bias and insufficient power of the included trials and the very low certainty of the available evidence, vitamin D supplementation versus placebo or no intervention may increase or reduce all-cause mortality, liver-related mortality, serious adverse events, or non-serious adverse events in adults with chronic liver diseases. There is a lack of data on liver-related morbidity and health-related quality of life. Further evidence on clinically important outcomes analysed in this review is needed.

Cumulative meta-analysis: What works

To present time-varying evidence, cumulative meta-analysis (CMA) updates results of previous meta-analyses to incorporate new study results. We investigate the properties of CMA, suggest possible improvements and provide the first in-depth simulation study of the use of CMA and CUSUM methods for detection of temporal trends in random-effects meta-analysis. We use the standardized mean difference (SMD) as an effect measure of interest. For CMA, we compare the standard inverse-variance-weighted estimation of the overall effect using REML-based estimation of between-study variance τ 2 with the sample-size-weighted estimation of the effect accompanied by Kulinskaya-Dollinger-Bjørkestøl (Biometrics. 2011; 67:203-212) (KDB) estimation of τ 2 . For all methods, we consider Type 1 error under no shift and power under a shift in the mean in the random-effects model. To ameliorate the lack of power in CMA, we introduce two-stage CMA, in which τ 2 is estimated at Stage 1 (from the first 5-10 studies), and further CMA monitors a target value of effect, keeping the τ 2 value fixed. We recommend this two-stage CMA combined with cumulative testing for positive shift in τ 2 . In practice, use of CMA requires at least 15-20 studies.

Laser therapy for dentinal hypersensitivity

BACKGROUND

Dentinal hypersensitivity is characterized by short, sharp pain from exposed dentine that occurs in response to external stimuli such as cold, heat, osmotic, tactile or chemicals, and cannot be explained by any other form of dental defect or pathology. Laser therapy has become a commonly used intervention and might be effective for dentinal hypersensitivity.

OBJECTIVES

To assess the effects of in-office employed lasers versus placebo laser, placebo agents or no treatment for relieving pain of dentinal hypersensitivity.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 20 October 2020), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2020, Issue 9), MEDLINE Ovid (1946 to 20 October 2020), Embase Ovid (1980 to 20 October 2020), CINAHL EBSCO (Cumulative Index to Nursing and Allied Health Literature; 1937 to 20 October 2020), and LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; from 1982 to 20 October 2020). Conference proceedings were searched via the ISI Web of Science and ZETOC, and OpenGrey was searched for grey literature. The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

Randomized controlled trials (RCTs) in which in-office lasers were compared to placebo or no treatment on patients aged above 12 years with tooth hypersensitivity.

DATA COLLECTION AND ANALYSIS

Two review authors independently and in duplicate screened the search results, extracted data, and assessed the risk of bias of the included studies. Disagreement was resolved by discussion. For continuous outcomes, we used mean differences (MD) and 95% confidence intervals (CI). We conducted meta-analyses only with studies of similar comparisons reporting the same outcome measures. We assessed the overall certainty of the evidence using GRADE.

MAIN RESULTS

We included a total of 23 studies with 936 participants and 2296 teeth. We assessed five studies at overall low risk of bias, 13 at unclear, and five at high risk of bias. 17 studies contributed data to the meta-analyses. We divided the studies into six subgroups based on the type of laser and the primary outcome measure. We assessed the change in intensity of pain using quantitative pain scale (visual analogue scale (VAS) of 0 to 10 (no pain to worst possible pain)) when tested through air blast and tactile stimuli in three categories of short (0 to 24 hours), medium (more than 24 hours to 2 months), and long term (more than 2 months). Results demonstrated that compared to placebo or no treatment the application of all types of lasers combined may reduce pain intensity when tested through air blast stimuli at short term (MD -2.24, 95% CI -3.55 to -0.93; P = 0.0008; 13 studies, 978 teeth; low-certainty evidence), medium term (MD -2.46, 95% CI -3.57 to -1.35; P < 0.0001; 11 studies, 1007 teeth; very low-certainty evidence), and long term (MD -2.60, 95% CI -4.47 to -0.73; P = 0.006; 5 studies, 564 teeth; very low-certainty evidence). Similarly, compared to placebo or no treatment the application of all types of lasers combined may reduce pain intensity when tested through tactile stimuli at short term (MD -0.67, 95% CI -1.31 to -0.03; P = 0.04; 8 studies, 506 teeth; low-certainty evidence) and medium term (MD -1.73, 95% CI -3.17 to -0.30; P = 0.02; 9 studies, 591 teeth; very low-certainty evidence). However, there was insufficient evidence of a difference in pain intensity for all types of lasers when tested through tactile stimuli in the long term (MD -3.52, 95% CI -10.37 to 3.33; P = 0.31; 2 studies, 184 teeth; very low-certainty evidence). Most included studies assessed adverse events and reported that no obvious adverse events were observed during the trials. No studies investigated the impact of laser treatment on participants' quality of life.

AUTHORS' CONCLUSIONS

Limited and uncertain evidence from meta-analyses suggests that the application of laser overall may improve pain intensity when tested through air blast or tactile stimuli at short, medium, or long term when compared to placebo/no treatment. Overall, laser therapy appears to be safe. Future studies including well-designed double-blinded RCTs are necessary to further investigate the clinical efficacy of lasers as well as their cost-effectiveness.

Cannabinoids, cannabis, and cannabis-based medicines for pain management: an overview of systematic reviews

ABSTRACT

Cannabinoids, cannabis, and cannabis-based medicines (CBM) are increasingly used to manage pain, with limited understanding of their efficacy and safety. We assessed methodological quality, scope, and results of systematic reviews of randomised controlled trials of these treatments. Several search strategies sought self-declared systematic reviews. Methodological quality was assessed using both AMSTAR-2 and techniques important for bias reduction in pain studies. Of the 106 articles read, 57 were self-declared systematic reviews, most published since 2010. They included any type of cannabinoid, cannabis, or CBM, at any dose, however administered, in a broad range of pain conditions. No review examined the effects of a particular cannabinoid, at a particular dose, using a particular route of administration, for a particular pain condition, reporting a particular analgesic outcome. Confidence in the results in the systematic reviews using AMSTAR-2 definitions was critically low (41), low (8), moderate (6), or high (2). Few used criteria important for bias reduction in pain. Cochrane reviews typically provided higher confidence; all industry-conflicted reviews provided critically low confidence. Meta-analyses typically pooled widely disparate studies, and, where assessable, were subject to potential publication bias. Systematic reviews with positive or negative recommendation for use of cannabinoids, cannabis, or CBM in pain typically rated critically low or low (24/25 [96%] positive; 10/12 [83%] negative). Current reviews are mostly lacking in quality and cannot provide a basis for decision-making. A new high-quality systematic review of randomised controlled trials is needed to critically assess the clinical evidence for cannabinoids, cannabis, or CBM in pain.

Fragility index of urological literature regarding medical expulsive treatment

INTRODUCTION

The role of medical expulsive treatment (MET) is controversial. Fragility index is an additional metric to assess randomized controlled trials (RCTs) outcome validity and indicates how many patients would be required to convert a trial from being statistically significant, to not significant. The larger is the FI, the better the trial's data. The aim of this study is to assess FI of RCTs regarding MET for ureteral stones.

MATERIALS AND METHODS

A systematic literature search was performed. RCTs, reporting stone expulsion as a dichotomous outcome, showing statistical significance were eligible. FI (the number of patients needed to change from a non-event to event group, to lose statistical significance) and Fragility quotient (FI divided by total sample size), were calculated while Pearson's correlation and Mann-Whitney U test were used as appropriate.

RESULTS

Thirty-six RCTs were eligible, with median FI = 3.5 and fragility quotient = 0.042, median sample size = 81, median journal impact factor = 1.73 and median reported p value = 0.008. In 33.3% of the studies, number of patients lost during follow-up was larger than FI, while in 13.89% of the studies, FI was 0, indicating use of inappropriate statistical method. Pearson's correlation showed significant positive association between FI and sample size (r = 0.981), number of events (r = 0.982) and impact factor (r = 0.731), while no association was found with p value or publication year.

CONCLUSIONS

In this analysis, a calculated FI of 3.5 indicates that findings from RCTs on MET for ureteral stones are fragile and should be interpreted in combination with clinical thinking and expertise.

Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site development

BACKGROUND

Alveolar bone changes following tooth extraction can compromise prosthodontic rehabilitation. Alveolar ridge preservation (ARP) has been proposed to limit these changes and improve prosthodontic and aesthetic outcomes when implants are used. This is an update of the Cochrane Review first published in 2015.

OBJECTIVES

To assess the clinical effects of various materials and techniques for ARP after tooth extraction compared with extraction alone or other methods of ARP, or both, in patients requiring dental implant placement following healing of extraction sockets.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 19 March 2021), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2021, Issue 2), MEDLINE Ovid (1946 to 19 March 2021), Embase Ovid (1980 to 19 March 2021), Latin American and Caribbean Health Science Information database (1982 to 19 March 2021), Web of Science Conference Proceedings (1990 to 19 March 2021), Scopus (1966 to 19 March 2021), ProQuest Dissertations and Theses (1861 to 19 March 2021), and OpenGrey (to 19 March 2021). The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. A number of journals were also handsearched.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) on the use of ARP techniques with at least six months of follow-up. Outcome measures were: changes in the bucco-lingual/palatal width of alveolar ridge, changes in the vertical height of the alveolar ridge, complications, the need for additional augmentation prior to implant placement, aesthetic outcomes, implant failure rates, peri-implant marginal bone level changes, changes in probing depths and clinical attachment levels at teeth adjacent to the extraction site, and complications of future prosthodontic rehabilitation.

DATA COLLECTION AND ANALYSIS

We selected trials, extracted data, and assessed risk of bias in duplicate. Corresponding authors were contacted to obtain missing information. We estimated mean differences (MD) for continuous outcomes and risk ratios (RR) for dichotomous outcomes, with 95% confidence intervals (95% CI). We constructed 'Summary of findings' tables to present the main findings and assessed the certainty of the evidence using GRADE.

MAIN RESULTS

We included 16 RCTs conducted worldwide involving a total of 524 extraction sites in 426 adult participants. We assessed four trials as at overall high risk of bias and the remaining trials at unclear risk of bias. Nine new trials were included in this update with six new trials in the category of comparing ARP to extraction alone and three new trials in the category of comparing different grafting materials. ARP versus extraction: from the seven trials comparing xenografts with extraction alone, there is very low-certainty evidence of a reduction in loss of alveolar ridge width (MD -1.18 mm, 95% CI -1.82 to -0.54; P = 0.0003; 6 studies, 184 participants, 201 extraction sites), and height (MD -1.35 mm, 95% CI -2.00 to -0.70; P < 0.0001; 6 studies, 184 participants, 201 extraction sites) in favour of xenografts, but we found no evidence of a significant difference for the need for additional augmentation (RR 0.68, 95% CI 0.29 to 1.62; P = 0.39; 4 studies, 154 participants, 156 extraction sites; very low-certainty evidence) or in implant failure rate (RR 1.00, 95% CI 0.07 to 14.90; 2 studies, 70 participants/extraction sites; very low-certainty evidence). From the one trial comparing alloplasts versus extraction, there is very low-certainty evidence of a reduction in loss of alveolar ridge height (MD -3.73 mm; 95% CI -4.05 to -3.41; 1 study, 15 participants, 60 extraction sites) in favour of alloplasts. This single trial did not report any other outcomes. Different grafting materials for ARP: three trials (87 participants/extraction sites) compared allograft versus xenograft, two trials (37 participants, 55 extraction sites) compared alloplast versus xenograft, one trial (20 participants/extraction sites) compared alloplast with and without membrane, one trial (18 participants, 36 extraction sites) compared allograft with and without synthetic cell-binding peptide P-15, and one trial (30 participants/extraction sites) compared alloplast with different particle sizes. The evidence was of very low certainty for most comparisons and insufficient to determine whether there are clinically significant differences between different ARP techniques based on changes in alveolar ridge width and height, the need for additional augmentation prior to implant placement, or implant failure. We found no trials which evaluated parameters relating to clinical attachment levels, specific aesthetic or prosthodontic outcomes for any of the comparisons. No serious adverse events were reported with most trials indicating that the procedure was uneventful. Among the complications reported were delayed healing with partial exposure of the buccal plate at suture removal, postoperative pain and swelling, moderate glazing, redness and oedema, membrane exposure and partial loss of grafting material, and fibrous adhesions at the cervical part of previously preserved sockets, for the comparisons xenografts versus extraction, allografts versus xenografts, alloplasts versus xenografts, and alloplasts with and without membrane.

AUTHORS' CONCLUSIONS

ARP techniques may minimise the overall changes in residual ridge height and width six months after extraction but the evidence is very uncertain. There is lack of evidence of any differences in the need for additional augmentation at the time of implant placement, implant failure, aesthetic outcomes, or any other clinical parameters due to lack of information or long-term data. There is no evidence of any clinically significant difference between different grafting materials and barriers used for ARP. Further long-term RCTs that follow CONSORT guidelines (www.consort-statement.org) are necessary.

A network meta-analysis of psychological interventions for schizophrenia and psychosis: Impact on symptoms

BACKGROUND

Evidence for the effectiveness of psychological interventions for schizophrenia/psychosis is growing, however there is no consensus on the psychological intervention most likely to reduce symptoms.

METHODS

A network meta-analysis was conducted to identify all randomised controlled trials (RCTs) of psychological interventions for adults with schizophrenia/psychosis. A systematic review of the literature using MEDLINE, PsycINFO, EMBASE and CENTRAL led to an analysis of 90 RCTs with 8440 randomised participants across 24 psychological intervention, and control groups. Psychological interventions were categorised and rated for treatment fidelity and risk of bias. Data for total symptoms were extracted and network meta-analysis, using a frequentist approach, was undertaken using Stata SE v15 to compare the direct and indirect evidence for the effectiveness of each psychological intervention.

FINDINGS

Psychological interventions were more likely to reduce symptoms than control groups, and one intervention, mindfulness-based psychoeducation, was consistently ranked as most likely to reduce total symptoms. Subgroup analyses identified differential effectiveness in different settings and for different subgroups.

INTERPRETATION

Mindfulness-based psychoeducation was consistently ranked as most likely to reduce symptoms; however all studies were based in China. More RCTs in a variety of cultural contexts would help to elucidate whether these findings generalise internationally. A number of psychological interventions could potentially be more effective than interventions recommended by NICE guidelines, such as CBT and family therapy, and additional RCTs and meta-analyses are needed to generate more conclusive evidence in this regard.

Risk Factors for Contra-Lateral Secondary Anterior Cruciate Ligament Injury: A Systematic Review with Meta-Analysis

Background

The risk of sustaining a contra-lateral anterior cruciate ligament (C-ACL) injury after primary unilateral ACL injury is high. C-ACL injury often contributes to a further decline in function and quality of life, including failure to return to sport. There is, however, very limited knowledge about which risk factors that contribute to C-ACL injury.

Objective

To systematically review instrinsic risk factors for sustaining a C-ACL injury.

Methods

A systematic review with meta-analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Four databases (MEDLINE, CINAHL, EMBASE, Sport Discus) were searched from inception to January 2020. Inclusion criteria were prospective or retrospective studies investigating any intrinsic risk factor for future C-ACL injury. Meta-analysis was performed and expressed as odds ratios (OR) if two or more articles assessed the same risk factor.

Results

44 moderate-to-high quality studies were eventually included in this review, whereof 35 studies were eligible for meta-analysis, including up to 59 000 individuals. We identified seven factors independently increasing the odds of sustaining a C-ACL injury (in order of highest to lowest OR): (1) returning to a high activity level (OR 3.26, 95% CI 2.10–5.06); (2) Body Mass Index < 25 (OR 2.73, 95% CI 1.73–4.36); (3) age ≤ 18 years (OR 2.42, 95% CI 1.51–3.88); (4) family history of ACL injury (OR 2.07, 95% CI 1.54–2.80); (5) primary ACL reconstruction performed ≤ 3 months post injury (OR 1.65, 95% CI: 1.32–2.06); (6) female sex (OR 1.35, 95% CI 1.14–1.61); and (7) concomitant meniscal injury (OR 1.21, 95% CI 1.03–1.42). The following two factors were associated with decreased odds of a subsequent C-ACL injury: 1) decreased intercondylar notch width/width of the distal femur ratio (OR 0.43, 95% CI 0.25–0.69) and 2) concomitant cartilage injury (OR 0.83, 95% CI 0.69–1.00). There were no associations between the odds of sustaining a C-ACL injury and smoking status, pre-injury activity level, playing soccer compared to other sports or timing of return to sport. No studies of neuromuscular function in relation to risk of C-ACL injury were eligible for meta-analysis according to our criteria.

Conclusion

This review provides evidence that demographic factors such as female sex, young age (≤ 18 years) and family history of ACL injury, as well as early reconstruction and returning to a high activity level increase the risk of C-ACL injury. Given the lack of studies related to neuromuscular factors that may be modifiable by training, future studies are warranted that investigate the possible role of factors such as dynamic knee stability and alignment, muscle activation and/or strength and proprioception as well as sport-specific training prior to return-to-sport for C-ACL injuries.

PROSPERO: CRD42020140129.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40279-020-01424-3.

Does enamel matrix derivative application provide additional clinical benefits in the treatment of maxillary Miller class I and II gingival recession? A systematic review and meta-analysis

OBJECTIVE

This review aimed to evaluate the effects of enamel matrix derivative (EMD) in association with coronally advanced flap (CAF) or CAF + connective tissue graft (CTG) when compared with CAF alone or CAF + CTG for the treatment of gingival recessions (GR) in maxillary teeth.

METHODS

Five databases and gray literature were searched up to April 2020, to find randomized clinical trials comparing the clinical effects of CAF + EMD versus CAF alone (first group) or CAF + CTG + EMD versus CAF + CTG (second group) in the treatment of Miller class I and II or Cairo type I gingival recessions (GR). Random effects model of mean differences was used to determine the GR reduction, gain in keratinized tissue width (KTW), and gain in clinical attachment level (CAL). The trial sequential analysis (TSA) was implemented to determine the optimal information size (OIS) and imprecision using the GRADE approach. Bayes factors were calculated as complementary statistical evidence of p value.

RESULTS

From 1349 titles identified, 9 trials representing 336 GR were included. The meta-analysis showed a statistically significant difference for GR reduction and CAL gain in favor CAF + EMD (p ≤ 0.05). The additional effect of EMD showed a statistically significant difference in GR reduction in favor CAF + CTG + EMD (p ≤ 0.05). The differences in KTW gain proved to be not statistically significant in both comparison groups. The OIS were not met among meta-analyses. Evidence certainty according the GRADE approach proved to be moderate for GR reduction and gain in CAL, but very low for gain in KTW.

CONCLUSION

The adjunctive application of EMD in the treatment of GR in maxillary teeth either with CAF or CTG provided moderate certainty evidence in favor of their use for reduction in GR and gain in CAL at 6 and 12 months. However, their effect on the increase in keratinized tissue band height showed very low evidence certainty for its use.

CLINICAL RELEVANCE

To know if EMD could improve the results for root coverage.

The effects of acceptance and commitment therapy on the psychological and physical outcomes among cancer patients: A meta-analysis with trial sequential analysis

OBJECTIVE

The current study used meta-analysis and trial sequential analysis to estimate the effects of Acceptance and Commitment Therapy (ACT) on the psychological and physical distress of cancer patients, and to identify potential moderators in this body of research.

METHODS

A search of multiple databases in February 2020 identified 25 independent trials (17 randomized controlled trials, 8 non-randomized controlled trials; 2256 participants) on the effects of ACT among cancer patients. Trial sequential analysis (TSA) was used to determine whether the available evidence is sufficient to draw strong conclusions.

RESULTS

ACT significantly reduced cancer patients' psychological distress (g = 0.88), and improved psychological flexibility (g = 0.58), quality of life (g = 1.19), and sense of hope (g = 2.17). TSA showed that there was sufficient evidence to obtain stable estimates of the effect of ACT on psychological distress and quality of life. Effect sizes for psychological distress were larger in studies conducted in eastern countries, in younger samples, and when therapy was of longer duration.

CONCLUSION

Acceptance and Commitment Therapy can effectively improve the mental health of cancer patients, and can be applied to clinical practice as an effective psychological intervention. Researchers are encouraged to take into account stage and trajectory of cancer in future studies.

Using Trial Sequential Analysis for estimating the sample sizes of further trials: example using smoking cessation intervention

Background

Assessing benefits and harms of health interventions is resource-intensive and often requires feasibility and pilot trials followed by adequately powered randomised clinical trials. Data from feasibility and pilot trials are used to inform the design and sample size of the adequately powered randomised clinical trials. When a randomised clinical trial is conducted, results from feasibility and pilot trials may be disregarded in terms of benefits and harms.

Methods

We describe using feasibility and pilot trial data in the Trial Sequential Analysis software to estimate the required sample size for one or more trials investigating a behavioural smoking cessation intervention. We show how data from a new, planned trial can be combined with data from the earlier trials using trial sequential analysis methods to assess the intervention’s effects.

Results

We provide a worked example to illustrate how we successfully used the Trial Sequential Analysis software to arrive at a sensible sample size for a new randomised clinical trial and use it in the argumentation for research funds for the trial.

Conclusions

Trial Sequential Analysis can utilise data from feasibility and pilot trials as well as other trials, to estimate a sample size for one or more, similarly designed, future randomised clinical trials. As this method uses available data, estimated sample sizes may be smaller than they would have been using conventional sample size estimation methods.

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.

Do knee abduction kinematics and kinetics predict future anterior cruciate ligament injury risk? A systematic review and meta-analysis of prospective studies

BACKGROUND

To systematically review the association between knee abduction kinematics and kinetics during weight-bearing activities at baseline and the risk of future anterior cruciate ligament (ACL) injury.

METHODS

Systematic review and meta-analysis according to PRISMA guidelines. A search in the databases MEDLINE (PubMed), CINAHL, EMBASE and Scopus was performed. Inclusion criteria were prospective studies including people of any age, assessing baseline knee abduction kinematics and/or kinetics during any weight-bearing activity for the lower extremity in individuals sustaining a future ACL injury and in those who did not.

RESULTS

Nine articles were included in this review. Neither 3D knee abduction angle at initial contact (Mean diff: -1.68, 95%CI: - 4.49 to 1.14, ACL injury n = 66, controls n = 1369), peak 3D knee abduction angle (Mean diff: -2.17, 95%CI: - 7.22 to 2.89, ACL injury n = 25, controls n = 563), 2D peak knee abduction angle (Mean diff: -3.25, 95%CI: - 9.86 to 3.36, ACL injury n = 8, controls n = 302), 2D medial knee displacement (cm; Mean diff:: -0.19, 95%CI: - 0,96 to 0.38, ACL injury n = 72, controls n = 967) or peak knee abduction moment (Mean diff:-10.61, 95%CI: - 26.73 to 5.50, ACL injury n = 54, controls n = 1330) predicted future ACL injury.

CONCLUSION

Contrary to clinical opinion, our findings indicate that knee abduction kinematics and kinetics during weight-bearing activities may not be risk factors for future ACL injury. Knee abduction of greater magnitude than that observed in the included studies as well as factors other than knee abduction angle or moment, as possible screening measures for knee injury risk should be evaluated in future studies.

Profiling Detection and Classification of Lameness Methods in British Dairy Cattle Research: A Systematic Review and Meta-Analysis

Lameness is a serious concern in the dairy sector, reflecting its high incidence and impact on animal welfare and productivity. Research has provided figures on its frequency using different methodologies, making it difficult to compare results and hindering farm-level decision-making. The study's objectives were to determine the frequency levels of lameness in British dairy cattle through a meta-analysis approach, and to understand the chronological patterns of how lameness cases are detected and classified in scientific research. A systematic review was conducted using PRISMA-P guidelines for article selection. Random-effects models estimated the pooled frequency measure of lameness with heterogeneity managed through subgroup analysis and meta-regression. Sixty-eight papers were identified, 50 included prevalence and 36 incidence data. The pooled prevalence of lameness in British dairy cattle was estimated at 29.5% (95% CI 26.7-32.4%) whilst all-cause lameness incidence rate indicated 30.9 cases of lameness per 100 cow-years (95% CI 24.5-37.9). The pooled cause-specific lameness incidence rate per 100 cow-years was 66.1 (95% CI 24.1-128.8) for white line disease, 53.2 (95% CI 20.5-101.2) for sole ulcer, 53.6 (95% CI 19.2-105.34) for digital dermatitis, with 51.9 (95% CI 9.3-129.2) attributable to other lameness-related lesions. Heterogeneity levels remained high. Sixty-nine papers contributed to a chronological overview of lameness data source. Although the AHDB Dairy mobility scoring system (MSS) was launched in the UK in 2008 and adopted shortly after by the British Dairy sector as the standard tool for assessing lameness, other methods are used depending on the investigator. Automated lameness detection systems may offer a solution for the subjective nature of MSSs, yet it was utilized in one study only. Despite the recognition of under-reporting of lameness from farm records 22 (31.9%) studies used this data source. The diversity of lameness data collection methods and sources was a key finding. It limits the understanding of lameness burden and the refinement of policy making for lameness. Standardizing case definition and research methods would improve knowledge of and ability to manage lameness. Regardless of the measurement method lameness in British dairy cattle is high.

Antioxidant micronutrient supplementation in critically ill adults: A systematic review with meta-analysis and trial sequential analysis

BACKGROUND

The role of antioxidant micronutrient (AxM) supplementation in the critically ill patients has been controversial, and recent trials have suggested a tendency to harm. Therefore, we performed a systematic review with meta-analysis and trial sequential analysis (TSA) of randomized controlled trials (RCT) to examine the effect of AxM supplementation on clinical outcomes among critically ill adults.

METHODS

PubMed, EMBASE, Cochrane, CINAHL, LILACS, DARE, SCOPUS, and Web of sciences databases were searched from inception to March 2019. RCTs that compared AxM supplements with placebo in adult critically ill patients and reporting mortality as an outcomes were included. Trial quality was assessed using updated cochrane risk of bias (RoB-II) tool. Primary outcome was all-cause mortality. Secondary outcomes were 28-day mortality, intensive care unit (ICU) and hospital length of stay (LOS), ventilator days and infection between the two groups. Outcomes were summarised using random-effects estimators. Quality of evidence (QOE) was rated using Grading of Recommendations, Assessment, Development and Evaluation. Prior to final analysis, we repeated the search through September 2019. R version 3.6.2 and STATA version 13 were used for all statistical analyses.

RESULTS

Pooled analysis of 34 trials with 4678 patients revealed that AxM supplementation was associated with possible reduction in all-cause mortality (relative risk [RR], 0.89 [95%CI 0.79 to 0.99], TSA adjusted CI 0.77 to 1.03; Low QOE). Fragility index and number needed to treat were 1 and 41, respectively. Eight studies with low RoB (RR, 1.08; 95%CI 0.95 to 1.23; TSA CI, 0.64 to 1.82; moderate QOE) did not show mortality reduction with AxM supplementation.

SECONDARY OUTCOMES

ICU LOS (weighted mean difference [WMD], -0.84; 95%CI -1.50 to -0.18; moderate QOE), hospitalization days (WMD, -2.83; 95%CI -3.91to -1.75; low QOE) and ventilator days (WMD, -1.87; 95%CI -3.60 to -0.14; very low QOE) showed a statistically significant benefit with AxM supplementation. In meta-regression analysis, neither the duration of AxM therapy nor the dosage of selenium, which was the most widely studied AxM, reported an association with mortality.

CONCLUSION

Although AxM supplementation was associated with possible reduction in all-cause mortality, results from the TSA and studies with low RoB showing null effect suggest that the evidence of benefit is questionable. Secondary outcomes attained statistically significant benefit with AxM supplements, but the certainity of evidence was low. To summarize, current evidence does not justify administration of AxM in critically ill patients.

REGISTRATION

PROSPERO, CRD42019125898.