Improvement of postoperative pain and other perioperative outcomes remain a significant challenge and a matter of debate among perioperative clinicians. This systematic review aims to evaluate the effects of perioperative i.v. lidocaine infusion on postoperative pain and recovery in patients undergoing various surgical procedures. CENTRAL, MEDLINE, EMBASE, and CINAHL databases and ClinicalTrials.gov, and congress proceedings were searched for randomized controlled trials until May 2014, that compared patients who did or did not receive continuous perioperative i.v. lidocaine infusion. Forty-five trials (2802 participants) were included. Meta-analysis suggested that lidocaine reduced postoperative pain (visual analogue scale, 0 to 10 cm) at 1-4 h (MD -0.84, 95% CI -1.10 to -0.59) and at 24 h (MD -0.34, 95% CI -0.57 to -0.11) after surgery, but not at 48 h (MD -0.22, 95% CI -0.47 to 0.03). Subgroup analysis and trial sequential analysis suggested pain reduction for patients undergoing laparoscopic abdominal surgery or open abdominal surgery, but not for patients undergoing other surgeries. There was limited evidence of positive effects of lidocaine on postoperative gastrointestinal recovery, opioid requirements, postoperative nausea and vomiting, and length of hospital stay. There were limited data available on the effect of systemic lidocaine on adverse effects or surgical complications. Quality of evidence was limited as a result of inconsistency (heterogeneity) and indirectness (small studies). There is limited evidence suggesting that i.v. lidocaine may be a useful adjuvant during general anaesthesia because of its beneficial impact on several outcomes after surgery.

Background Ivermectin, an antiparasitic agent used to treat parasitic infestations, inhibits the replication of viruses in vitro. The molecular hypothesis of ivermectin's antiviral mode of action suggests an inhibitory effect on severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) replication in the early stages of infection. Currently, evidence on efficacy and safety of ivermectin for prevention of SARS‐CoV‐2 infection and COVID‐19 treatment is conflicting. Objectives To assess the efficacy and safety of ivermectin compared to no treatment, standard of care, placebo, or any other proven intervention for people with COVID‐19 receiving treatment as inpatients or outpatients, and for prevention of an infection with SARS‐CoV‐2 (postexposure prophylaxis). Search methods We searched the Cochrane COVID‐19 Study Register, Web of Science (Emerging Citation Index and Science Citation Index), medRxiv, and Research Square, identifying completed and ongoing studies without language restrictions to 26 May 2021. Selection criteria We included randomized controlled trials (RCTs) comparing ivermectin to no treatment, standard of care, placebo, or another proven intervention for treatment of people with confirmed COVID‐19 diagnosis, irrespective of disease severity, treated in inpatient or outpatient settings, and for prevention of SARS‐CoV‐2 infection. Co‐interventions had to be the same in both study arms. We excluded studies comparing ivermectin to other pharmacological interventions with unproven efficacy. Data collection and analysis We assessed RCTs for bias, using the Cochrane risk of bias 2 tool. The primary analysis excluded studies with high risk of bias. We used GRADE to rate the certainty of evidence for the following outcomes 1. to treat inpatients with moderate‐to‐severe COVID‐19: mortality, clinical worsening or improvement, adverse events, quality of life, duration of hospitalization, and viral clearance; 2. to treat outpatients with mild COVID‐19: mortality, clinical worsening or improvement, admission to hospital, adverse events, quality of life, and viral clearance; (3) to prevent SARS‐CoV‐2 infection: SARS‐CoV‐2 infection, development of COVID‐19 symptoms, adverse events, mortality, admission to hospital, and quality of life. Main results We found 14 studies with 1678 participants investigating ivermectin compared to no treatment, placebo, or standard of care. No study compared ivermectin to an intervention with proven efficacy. There were nine studies treating participants with moderate COVID‐19 in inpatient settings and four treating mild COVID‐19 cases in outpatient settings. One study investigated ivermectin for prevention of SARS‐CoV‐2 infection. Eight studies had an open‐label design, six were double‐blind and placebo‐controlled. Of the 41 study results contributed by included studies, about one third were at overall high risk of bias. Ivermectin doses and treatment duration varied among included studies. We identified 31 ongoing and 18 studies awaiting classification until publication of results or clarification of inconsistencies. Ivermectin compared to placebo or standard of care for inpatient COVID‐19 treatment We are uncertain whether ivermectin compared to placebo or standard of care reduces or increases mortality (risk ratio (RR) 0.60, 95% confidence interval (CI) 0.14 to 2.51; 2 studies, 185 participants; very low‐certainty evidence) and clinical worsening up to day 28 assessed as need for invasive mechanical ventilation (IMV) (RR 0.55, 95% CI 0.11 to 2.59; 2 studies, 185 participants; very low‐certainty evidence) or need for supplemental oxygen (0 participants required supplemental oxygen; 1 study, 45 participants; very low‐certainty evidence), adverse events within 28 days (RR 1.21, 95% CI 0.50 to 2.97; 1 study, 152 participants; very low‐certainty evidence), and viral clearance at day seven (RR 1.82, 95% CI 0.51 to 6.48; 2 studies, 159 participants; very low‐certainty evidence). Ivermectin may have little or no effect compared to placebo or standard of care on clinical improvement up to 28 days (RR 1.03, 95% CI 0.78 to 1.35; 1 study; 73 participants; low‐certainty evidence) and duration of hospitalization (mean difference (MD) −0.10 days, 95% CI −2.43 to 2.23; 1 study; 45 participants; low‐certainty evidence). No study reported quality of life up to 28 days. Ivermectin compared to placebo or standard of care for outpatient COVID‐19 treatment We are uncertain whether ivermectin compared to placebo or standard of care reduces or increases mortality up to 28 days (RR 0.33, 95% CI 0.01 to 8.05; 2 studies, 422 participants; very low‐certainty evidence) and clinical worsening up to 14 days assessed as need for IMV (RR 2.97, 95% CI 0.12 to 72.47; 1 study, 398 participants; very low‐certainty evidence) or non‐IMV or high flow oxygen requirement (0 participants required non‐IMV or high flow; 1 study, 398 participants; very low‐certainty evidence). We are uncertain whether ivermectin compared to placebo reduces or increases viral clearance at seven days (RR 3.00, 95% CI 0.13 to 67.06; 1 study, 24 participants; low‐certainty evidence). Ivermectin may have little or no effect compared to placebo or standard of care on the number of participants with symptoms resolved up to 14 days (RR 1.04, 95% CI 0.89 to 1.21; 1 study, 398 participants; low‐certainty evidence) and adverse events within 28 days (RR 0.95, 95% CI 0.86 to 1.05; 2 studies, 422 participants; low‐certainty evidence). None of the studies reporting duration of symptoms were eligible for primary analysis. No study reported hospital admission or quality of life up to 14 days. Ivermectin compared to no treatment for prevention...

Evidence synthesis findings depend on the assumption that the included studies follow good clinical practice and results are not fabricated or false. Studies which are problematic due to scientific misconduct, poor research practice, or honest error may distort evidence synthesis findings. Authors of evidence synthesis need transparent mechanisms to identify and manage problematic studies to avoid misleading findings. As evidence synthesis authors of the Cochrane COVID‐19 review on ivermectin, we identified many problematic studies in terms of research integrity and regulatory compliance. Through iterative discussion, we developed a research integrity assessment (RIA) tool for randomized controlled trials for the update of this Cochrane review. In this paper, we explain the rationale and application of the RIA tool in this case study. RIA assesses six study criteria: study retraction, prospective trial registration, adequate ethics approval, author group, plausibility of methods (e.g., randomization), and plausibility of study results. RIA was used in the Cochrane review as part of the eligibility check during screening of potentially eligible studies. Problematic studies were excluded and studies with open questions were held in awaiting classification until clarified. RIA decisions were made independently by two authors and reported transparently. Using the RIA tool resulted in the exclusion of >40% of studies in the first update of the review. RIA is a complementary tool prior to assessing “Risk of Bias” aiming to establish the integrity and authenticity of studies. RIA provides a platform for urgent development of a standard approach to identifying and managing problematic studies.

Background: Systematic reviews attempt to gather all available evidence. Controversy exists regarding effort and benefit of including study results presented at conferences only. We recently published a Cochrane network meta-analysis (NMA) including 585 randomized controlled trials comparing drugs for prevention of postoperative nausea and vomiting (PONV). Studies published as conference abstracts only were excluded. This study aimed to include all eligible studies published as abstracts only, assessing their added value regarding reporting quality and effect on the review’s interpretation. Methods: Conference abstracts were searched in the review’s excluded studies and conference proceedings of anaesthesiologic societies. We assessed their reporting quality regarding review’s eligibility criteria, Cochrane ‘risk of bias’ assessment tool 1.0, and adherence to CONSORT (Consolidated Standards of Reporting Trials) for abstracts. Abstracts were included in sensitivity NMA, and impact on the NMA structure was investigated. Results: We identified 90 abstracts. A total of 14% (13/90) were eligible. A total of 86% (77/90) are awaiting classification due to insufficient reporting of review’s eligibility criteria. In abstracts awaiting classification, sufficient information was missing on standardization of anaesthesia in 71% (55/77), age of participants in 56% (43/77), and outcome details in 46% (36/77). A total of 73% (66/90) of abstracts lacked sufficient information on 15/25 data extraction items. Reported study characteristics of abstracts were comparable to included studies of the review. A total of 62% (56/90) of abstract trials were assessed as overall high risk of bias due to poor reporting. Median adherence to CONSORT for abstracts was 24% (IQR, 18 to 29%). Six of the 13 eligible abstracts reported relevant outcome data in sufficient detail for NMA on seven outcomes of the Cochrane review. Inclusion of abstracts did not substantially change the network structure, network effect estimates, ranking of treatments, or the conclusion. Certainty of evidence for headache on palonosetron use was upgraded from very low to low. Conclusions: Most conference abstracts on PONV were insufficiently reported regarding review’s narrow inclusion criteria and could not be included in NMA. The resource-intensive search and evaluation of abstracts did not substantially extent the full-text evidence base of the review, given the few adequately reported abstracts. Conferences should oblige authors to adhere to CONSORT for abstracts.

Background Oral nirmatrelvir/ritonavir (Paxlovid®) aims to avoid severe COVID‐19 in asymptomatic people or those with mild symptoms, thereby decreasing hospitalization and death. Due to its novelty, there are currently few published study results. It remains to be evaluated for which indications and patient populations the drug is suitable. Objectives To assess the efficacy and safety of nirmatrelvir/ritonavir (Paxlovid®) plus standard of care compared to standard of care with or without placebo, or any other intervention for treating COVID‐19 and for preventing SARS‐CoV‐2 infection. To explore equity aspects in subgroup analyses. To keep up to date with the evolving evidence base using a living systematic review (LSR) approach and make new relevant studies available to readers in‐between publication of review updates. Search methods We searched the Cochrane COVID‐19 Study Register, Scopus, and WHO COVID‐19 Global literature on coronavirus disease database, identifying completed and ongoing studies without language restrictions and incorporating studies up to 11 July 2022. This is a LSR. We conduct monthly update searches that are being made publicly available on the open science framework (OSF) platform. Selection criteria Studies were eligible if they were randomized controlled trials (RCTs) comparing nirmatrelvir/ritonavir plus standard of care with standard of care with or without placebo, or any other intervention for treatment of people with confirmed COVID‐19 diagnosis, irrespective of disease severity or treatment setting, and for prevention of SARS‐CoV‐2 infection. We screened all studies for research integrity. Studies were ineligible if they had been retracted, or if they were not prospectively registered including appropriate ethics approval. Data collection and analysis We followed standard Cochrane methodology and used the Cochrane risk of bias 2 tool. We rated the certainty of evidence using the GRADE approach for the following outcomes: 1. to treat outpatients with mild COVID‐19; 2. to treat inpatients with moderate‐to‐severe COVID‐19: mortality, clinical worsening or improvement, quality of life, (serious) adverse events, and viral clearance; 3. to prevent SARS‐CoV‐2 infection in post‐exposure prophylaxis (PEP); and 4. pre‐exposure prophylaxis (PrEP) scenarios: SARS‐CoV‐2 infection, development of COVID‐19 symptoms, mortality, admission to hospital, quality of life, and (serious) adverse events. We explored inequity by subgroup analysis for elderly people, socially‐disadvantaged people with comorbidities, populations from LICs and LMICs, and people from different ethnic and racial backgrounds. Main results As of 11 July 2022, we included one RCT with 2246 participants in outpatient settings with mild symptomatic COVID‐19 comparing nirmatrelvir/ritonavir plus standard of care with standard of care plus placebo. Trial participants were unvaccinated, without previous confirmed SARS‐CoV‐2 infection, had a symptom onset of no more than five days before randomization, and were at high risk for progression to severe disease. Prohibited prior or concomitant therapies included medications highly dependent on CYP3A4 for clearance and CYP3A4 inducers. We identified eight ongoing studies. Nirmatrelvir/ritonavir for treating COVID‐19 in outpatient settings with asymptomatic or mild disease For the specific population of unvaccinated, high‐risk patients nirmatrelvir/ritonavir plus standard of care compared to standard of care plus placebo may reduce all‐cause mortality at 28 days (risk ratio (RR) 0.04, 95% confidence interval (CI) 0.00 to 0.68; 1 study, 2224 participants; estimated absolute effect: 11 deaths per 1000 people receiving placebo compared to 0 deaths per 1000 people receiving nirmatrelvir/ritonavir; low‐certainty evidence, and admission to hospital or death within 28 days (RR 0.13, 95% CI 0.07 to 0.27; 1 study, 2224 participants; estimated absolute effect: 61 admissions or deaths per 1000 people receiving placebo compared to eight admissions or deaths per 1000 people receiving nirmatrelvir/ritonavir; low‐certainty evidence). Nirmatrelvir/ritonavir plus standard of care may reduce serious adverse events during the study period compared to standard of care plus placebo (RR 0.24, 95% CI 0.15 to 0.41; 1 study, 2224 participants; low‐certainty evidence). Nirmatrelvir/ritonavir plus standard of care probably has little or no effect on treatment‐emergent adverse events (RR 0.95, 95% CI 0.82 to 1.10; 1 study, 2224 participants; moderate‐certainty evidence), and probably increases treatment‐related adverse events such as dysgeusia and diarrhoea during the study period compared to standard of care plus placebo (RR 2.06, 95% CI 1.44 to 2.95; 1 study, 2224 participants; moderate‐certainty evidence). Nirmatrelvir/ritonavir plus standard of care probably decreases discontinuation of study drug due to adverse events compared to standard of care plus placebo (RR 0.49, 95% CI 0.30 to 0.80; 1 study, 2224 participants; moderate‐certainty evidence). No study results were identified for improvement of clinical status, quality of life, and viral clearance. Subgroup analyses for equity Most study participants were younger than 65 years (87.1% of the : modified intention to treat (mITT1) population with 2085 participants), of white ethnicity (71.5%), and were from UMICs or HICs (92.1% of study centres). Data on comorbidities were insufficient. The outcome ‘admission to hospital or death’ was investigated for equity: age (< 65 years versus ≥ 65 years) and ethnicity (Asian versus Black versus White versus others). There was no difference between subgroups of age. The effects favoured treatment with nirmatrelvir/ritonavir for the White ethnic group. Estimated effects in the other ethnic groups included the line of no effect (RR = 1). No subgroups were reported for comorbidity status and World Bank country classification by income level. No subgroups were reported for other outcomes. Nirmatrelvir/ritonavir for treating COVID‐19 in inpatient settings with moderate to severe disease No studies available. Nirmatrelvir/ritonavir for preventing SARS‐CoV‐2 infection (PrEP and PEP) No studies available. Authors' conclusions There is low‐certainty evidence that nirmatrelvir/ritonavir reduces the risk of all‐cause mortality and hospital admission or death based on one trial investigating unvaccinated COVID‐19 participants without previous infection that were at high risk and with symptom onset of no more than five days. There is low‐ to moderate‐certainty evidence that nirmatrelvir/ritonavir is safe in people without prior or concomitant therapies including medications highly dependent on CYP3A4. Regarding equity aspects, except for ethnicity, no differences in effect size and direction were identified. No evidence is available on nirmatrelvir/ritonavir to treat hospitalized people with COVID‐19 and to prevent a SARS‐CoV‐2 infection. We will continually update our search and make search results available on OSF.