BACKGROUND: Deep vein thrombosis (DVT) is a condition in which a clot forms in the deep veins, most commonly of the leg. It occurs in approximately one in 1000 people. If left untreated, the clot can travel up to the lungs and cause a potentially life-threatening pulmonary embolism (PE). Previously, a DVT was treated with the anticoagulants heparin and vitamin K antagonists. However, two forms of direct oral anticoagulants (DOACs) have been developed: oral direct thrombin inhibitors (DTIs) and oral factor Xa inhibitors, which have characteristics that may be favourable compared to conventional treatment, including oral administration, a predictable effect, lack of frequent monitoring or dose adjustment and few known drug interactions. DOACs are now commonly being used for treating DVT: recent guidelines recommended DOACs over conventional anticoagulants for both DVT and PE treatment. This Cochrane Review was first published in 2015. It was the first systematic review to measure the effectiveness and safety of these drugs in the treatment of DVT. This is an update of the 2015 review. OBJECTIVES: To assess the effectiveness and safety of oral DTIs and oral factor Xa inhibitors versus conventional anticoagulants for the long-term treatment of DVT.
SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 1 March 2022.
SELECTION CRITERIA: We included randomised controlled trials (RCTs) in which people with a DVT, confirmed by standard imaging techniques, were allocated to receive an oral DTI or an oral factor Xa inhibitor compared with conventional anticoagulation or compared with each other for the treatment of DVT. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were recurrent venous thromboembolism (VTE), recurrent DVT and PE. Secondary outcomes included all-cause mortality, major bleeding, post-thrombotic syndrome (PTS) and quality of life (QoL). We used GRADE to assess the certainty of evidence for each outcome.
MAIN RESULTS: We identified 10 new studies with 2950 participants for this update. In total, we included 21 RCTs involving 30,895 participants. Three studies investigated oral DTIs (two dabigatran and one ximelagatran), 17 investigated oral factor Xa inhibitors (eight rivaroxaban, five apixaban and four edoxaban) and one three-arm trial investigated both a DTI (dabigatran) and factor Xa inhibitor (rivaroxaban). Overall, the studies were of good methodological quality. Meta-analysis comparing DTIs to conventional anticoagulation showed no clear difference in the rate of recurrent VTE (odds ratio (OR) 1.17, 95% confidence interval (CI) 0.83 to 1.65; 3 studies, 5994 participants; moderate-certainty evidence), recurrent DVT (OR 1.11, 95% CI 0.74 to 1.66; 3 studies, 5994 participants; moderate-certainty evidence), fatal PE (OR 1.32, 95% CI 0.29 to 6.02; 3 studies, 5994 participants; moderate-certainty evidence), non-fatal PE (OR 1.29, 95% CI 0.64 to 2.59; 3 studies, 5994 participants; moderate-certainty evidence) or all-cause mortality (OR 0.66, 95% CI 0.41 to 1.08; 1 study, 2489 participants; moderate-certainty evidence). DTIs reduced the rate of major bleeding (OR 0.58, 95% CI 0.38 to 0.89; 3 studies, 5994 participants; high-certainty evidence). For oral factor Xa inhibitors compared with conventional anticoagulation, meta-analysis demonstrated no clear difference in recurrent VTE (OR 0.85, 95% CI 0.71 to 1.01; 13 studies, 17,505 participants; moderate-certainty evidence), recurrent DVT (OR 0.70, 95% CI 0.49 to 1.01; 9 studies, 16,439 participants; moderate-certainty evidence), fatal PE (OR 1.18, 95% CI 0.69 to 2.02; 6 studies, 15,082 participants; moderate-certainty evidence), non-fatal PE (OR 0.93, 95% CI 0.68 to 1.27; 7 studies, 15,166 participants; moderate-certainty evidence) or all-cause mortality (OR 0.87, 95% CI 0.67 to 1.14; 9 studies, 10,770 participants; moderate-certainty evidence). Meta-analysis showed a reduced rate of major bleeding with oral factor Xa inhibitors compared with conventional anticoagulation (OR 0.63, 95% CI 0.45 to 0.89; 17 studies, 18,066 participants; high-certainty evidence). AUTHORS' CONCLUSIONS: The current review suggests that DOACs may be superior to conventional therapy in terms of safety (major bleeding), and are probably equivalent in terms of efficacy. There is probably little or no difference between DOACs and conventional anticoagulation in the prevention of recurrent VTE, recurrent DVT, pulmonary embolism and all-cause mortality. DOACs reduced the rate of major bleeding compared to conventional anticoagulation. The certainty of evidence was moderate or high.
BACKGROUND: Factor Xa inhibitors and vitamin K antagonists (VKAs) are now recommended in treatment guidelines for preventing stroke and systemic embolic events in people with atrial fibrillation (AF). This is an update of a Cochrane review previously published in 2013.
OBJECTIVES: To assess the effectiveness and safety of treatment with factor Xa inhibitors versus VKAs for preventing cerebral or systemic embolic events in people with AF.
SEARCH METHODS: We searched the trials registers of the Cochrane Stroke Group and the Cochrane Heart Group (September 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) (August 2017), MEDLINE (1950 to April 2017), and Embase (1980 to April 2017). We also contacted pharmaceutical companies, authors and sponsors of relevant published trials. We used outcome data from marketing authorisation applications of apixaban, edoxaban and rivaroxaban that were submitted to regulatory authorities in Europe and the USA.
SELECTION CRITERIA: We included randomised controlled trials (RCTs) that directly compared the effects of long-term treatment (lasting more than four weeks) with factor Xa inhibitors versus VKAs for preventing cerebral and systemic embolism in people with AF.
DATA COLLECTION AND ANALYSIS: The primary efficacy outcome was the composite endpoint of all strokes and systemic embolic events. Two review authors independently extracted data, and assessed the quality of the trials and the risk of bias. We calculated a weighted estimate of the typical treatment effect across trials using the odds ratio (OR) with 95% confidence interval (CI) by means of a fixed-effect model. In case of moderate or high heterogeneity of treatment effects, we used a random-effects model to compare the overall treatment effects. We also performed a pre-specified sensitivity analysis excluding any open-label studies.
MAIN RESULTS: We included data from 67,688 participants randomised into 13 RCTs. The included trials directly compared dose-adjusted warfarin with either apixaban, betrixaban, darexaban, edoxaban, idraparinux, idrabiotaparinux, or rivaroxaban. The majority of the included data (approximately 90%) was from apixaban, edoxaban, and rivaroxaban.The composite primary efficacy endpoint of all strokes (both ischaemic and haemorrhagic) and non-central nervous systemic embolic events was reported in all of the included studies. Treatment with a factor Xa inhibitor significantly decreased the number of strokes and systemic embolic events compared with dose-adjusted warfarin in participants with AF (OR 0.89, 95% CI 0.82 to 0.97; 13 studies; 67,477 participants; high-quality evidence).Treatment with a factor Xa inhibitor significantly reduced the number of major bleedings compared with warfarin (OR 0.78, 95% CI 0.73 to 0.84; 13 studies; 67,396 participants; moderate-quality evidence). There was, however, statistically significant and high heterogeneity (I2 = 83%). When we repeated this analysis using a random-effects model, it did not show a statistically significant decrease in the number of major bleedings (OR 0.88, 95% CI 0.66 to 1.17). A pre-specified sensitivity analysis excluding all open-label studies showed that treatment with a factor Xa inhibitor significantly reduced the number of major bleedings compared with warfarin (OR 0.75, 95% CI 0.69 to 0.81), but high heterogeneity was also observed in this analysis (I2 = 72%). The same sensitivity analysis using a random-effects model also showed a statistically significant decrease in the number of major bleedings in participants treated with factor Xa inhibitors (OR 0.76, 95% CI 0.60 to 0.96).Treatment with a factor Xa inhibitor significantly reduced the risk of intracranial haemorrhages (ICHs) compared with warfarin (OR 0.50, 95% CI 0.42 to 0.59; 12 studies; 66,259 participants; high-quality evidence). We observed moderate, but statistically significant heterogeneity (I2 = 55%). The pre-specified sensitivity analysis excluding open-label studies showed that treatment with a factor Xa inhibitor significantly reduced the number of ICHs compared with warfarin (OR 0.47, 95% CI 0.40 to 0.56), with low, non-statistically significant heterogeneity (I2 = 27%).Treatment with a factor Xa inhibitor also significantly reduced the number of all-cause deaths compared with warfarin (OR 0.89, 95% 0.83 to 0.95; 10 studies; 65,624 participants; moderate-quality evidence).
AUTHORS' CONCLUSIONS: Treatment with factor Xa inhibitors significantly reduced the number of strokes and systemic embolic events compared with warfarin in people with AF. The absolute effect of factor Xa inhibitors compared with warfarin treatment was, however, rather small. Factor Xa inhibitors also reduced the number of ICHs, all-cause deaths and major bleedings compared with warfarin, although the evidence for a reduction in the latter is less robust.
Background A meta-analysis was performed to evaluate the risk of major bleeding with the use of New Oral Anticoagulants (NOACs). Methods Randomized controlled trials (RCTs) comparing NOACs (rivaroxaban, dabigatran, apixaban, edoxaban and darexaban) with comparators were selected. Results Fifty trials included 155,537 patients. Pooled analysis of all NOACs for all indications together demonstrated no significant difference between NOACs and comparators for risk of major bleeding (odds ratio [OR] 0.93, 95% CI 0.79-1.09). Pooled analysis also showed that NOACs caused significantly less major bleeding compared to vitamin K antagonists (VKA) (0.77, 0.64-0.91). The analysis for individual NOACs showed risk of major bleeding were not different with rivaroxaban, apixaban or dabigatran compared to pharmacologically active comparators or VKA. Indication specific analysis showed that NOACs were associated with significantly higher major bleeding after hip surgery (1.43, 1.02-1.99), in patients with acute coronary syndrome (ACS), (compared against placebo) (2.89, 2.01-4.14), and for medically ill patients (2.79, 1.69-4.60). For the treatment of acute venous thromboembolism (VTE) or pulmonary embolism (PE), NOACs were associated with significantly less bleeding (0.63, 0.44-0.90). No significant difference was found between NOACs and comparators in treatment of atrial fibrillation and for extended treatment of VTE. Conclusions Risk of major bleeding with new oral anticoagulants varies with their indication for use. New agents may be associated with comparatively less major bleeding compared to VKA. NOAC may increase the risk of major bleeding after hip surgery, ACS and acute medically ill patients; but may be associated with less bleeding in treatment of acute VTE/PE.
IMPORTANCE: In noninferiority trials, novel oral anticoagulants (NOACs), also known as non-vitamin K oral anticoagulants, were at least noninferior to standard care in the prevention of most prothrombotic conditions. However, differences exist in the safety profile of antithrombotic drugs, and little is known about their intraocular bleeding risk.
OBJECTIVE: To evaluate the risk of substantial intraocular bleeding associated with NOACs.
DATA SOURCES: MEDLINE, Cochrane Library, SciELO collection, and Web of Science databases were searched from inception to November 2014, as well as other systematic reviews and regulatory agencies documentation.
STUDY SELECTION: All phase 3 randomized clinical trials (RCTs) comparing NOACs with any other control that reported intraocular bleeding events.
DATA EXTRACTION AND SYNTHESIS: Data were extracted independently by 2 of the authors and pooled using random-effects meta-analysis. Heterogeneity was assessed with the I2 test.
MAIN OUTCOMES AND MEASURES: Substantial intraocular bleeding was evaluated with pooled risk ratios (RRs) and 95% CIs.
RESULTS: Seventeen RCTs were included. In patients with atrial fibrillation, no difference was identified between NOACs and vitamin K antagonists (RR, 0.84; 95% CI, 0.59-1.19; I2 = 35%; 5 RCTs), and no increased risk was identified compared with acetylsalicylic acid (RR, 14.96; 95% CI, 0.85-262.00; 1 RCT). In patients with venous thromboembolism, no increased risk of substantial intraocular bleeding compared with sequential treatment with low-molecular-weight heparin and a vitamin K antagonist (RR, 0.67; 95% CI, 0.37-1.20; I2 = 0%; 5 RCTs) was identified. Regarding patients who underwent orthopedic surgery, the risk was not different between NOACs and low-molecular-weight heparin (RR, 2.13; 95% CI, 0.22-20.50; I2 = 0%; 5 RCTs).
CONCLUSIONS AND RELEVANCE: Randomized data suggest that no differences exist in the risk of substantial intraocular bleeding between NOACs and other antithrombotic drugs. However, the number of events was scarce so that additional studies from larger databases that monitor patients under conditions of ophthalmologic routine clinical practice should be performed to better characterize the safety profile of NOACs.
Background: New oral anticoagulants represent an alternative to standard therapy with vitamin K antagonists but data regarding gastrointestinal bleeding are still unclear. Aims: To investigate if new oral anticoagulants are associated with an enhanced risk of gastrointestinal bleeding vs warfarin in patients with atrial fibrillation. Methods: Meta-analysis of phase three randomized controlled trials to compare the incidence of gastrointestinal bleeding in atrial fibrillation patients treated with new oral anticoagulants (apixaban, dabigatran, edoxaban and rivaroxaban) vs warfarin. Results: Four studies including 71,302 patients were selected. Compared with warfarin, new oral anticoagulants significantly increased gastrointestinal bleeding (RR: 1.23; 95% CI 1.03-1.46; p = 0.01). Rivaroxaban (RR: 1.46; 95% CI 1.2-1.8; p <. 0.001) and high dosages of edoxaban (RR: 1.22; 95% CI 1.01-1.47; p = 0.038) and dabigatran (RR: 1.50; 95% CI 1.20-1.88; p <. 0.001) significantly increased gastrointestinal bleeding while a null effect was detected with apixaban. Conclusions: This meta-analysis suggests that rivaroxaban and high dosages of dabigatran and edoxaban should be avoided in patients at high risk of gastrointestinal bleeding.
The new oral anticoagulants/non-vitamin K antagonists oral anticoagulants (NOACs) have recently reached the market and less is known about their safety in comparison to their efficacy. Therefore, we aimed to evaluate intracranial hemorrhage (ICH) risk with NOACs, the most feared adverse event of anticoagulation treatment. This is a systematic review and meta-analysis of phase III randomized controlled trials (RCTs) comparing NOACs versus any control and reporting ICH events. Studies were searched through Medline and Cochrane Library (April 2014). Reviews and reference lists were also screened. Random effects' meta-analysis was performed to derive pooled estimates expressed as relative risk (RR) and 95 % CI. Number needed to treat/harm (NNT/NNH) taking into account the baseline risk was also calculated. Heterogeneity was evaluated with I (2) test. 18 RCTs evaluating 148,149 patients were included. NOAC significantly reduced ICH risk compared to vitamin K antagonists (VKA) (RR 0.44; 95 % CI 0.36-0.54; I (2) = 37 %; NNT; 137 during 2 years) and to sequential treatment with low molecular weight heparin and VKA (RR 0.28; 95 % CI 0.12-0.65; I (2) = 0 %; NNT; 463 patients during 7 months). Compared to placebo, NOACs were associated with an increased ICH risk (RR 3.31; 95 % CI 1.59-6.90; I (2) = 0 %; NNH; 433 during 1 year). Results were similar for the different NOAC drugs and across the different clinical conditions. In patients requiring anticoagulation treatment, the risk of ICH is about half with the NOACs in comparison to standard antithrombotic treatment. This safer profile found in RCTs should be confirmed in real-world database studies.
BACKGROUND: Non-vitamin K antagonist oral anticoagulants (NOACs) are at least non-inferior to Vitamin K Antagonists (VKAs) for stroke prevention on patients with non-valvular atrial fibrillation (AF). We aimed to evaluate the efficacy and safety of NOACs in patients undergoing cardioversion through a systematic review and meta-analysis.
METHODS: MEDLINE, Cochrane Library, and Web of Science(®) databases (until September 2014) were searched for studies fulfilling inclusion criteria. Two reviewers independently selected randomized controlled trials (RCTs) evaluating NOACs and VKA in patients with AF undergoing cardioversion. The primary outcome was ischemic stroke or systemic embolism (IS/SE). Secondary outcomes were major bleeding, myocardial infarction, and mortality. Risk ratio (RR) and 95 % confidence intervals were derived through random-effects meta-analysis. Heterogeneity was evaluated through I (2) test.
RESULTS: Four RCTs (3 post-hoc analysis) evaluating apixaban, dabigatran, and rivaroxaban in 3,512 patients with AF were included. The risk of IS/SE with NOACs was similar to VKA (RR 0.60, 95 % CI 0.20-1.80; I (2) = 17 %). There was no significant increase in major bleeding (RR 1.27, 95 % CI 0.58-2.81; I (2) = 0 %), myocardial infarction (RR 0.71, 95 % CI 0.10-5.04; I (2) = 0 %), or mortality (RR 0.87, 95 % CI 0.24-3.08; I (2) = 0 %) with NOACs.
CONCLUSIONS: This systematic review and meta-analysis suggests that NOACs may be as safe as VKAs in the setting of AF cardioversion.
Background: Anticoagulation in cardioversion and ablation of atrial fibrillation is imperative for reducing thrombo-embolic events. Ample information is available about the use of warfarin and vitamin K antagonists (VKA) but few trials examine safety and efficacy of rivaroxaban in these procedures. We aim to explore the hypothesis that rivaroxaban causes equal thrombo-embolic and bleeding events when used in atrial fibrillation patients undergoing ablation or cardioversion compared to VKA. Methods: We searched the online databases as well as conference abstracts till December 2014 for studies comparing rivaroxaban with VKA in atrial fibrillation patients undergoing catheter ablation or cardioversion. We report events as Odds ratio using random effects model except when event rates were less than 1% we used Peto Odds Ratio. Results: A total of 8872 atrial fibrillation patients in 15 studies undergoing either catheter ablation or cardioversion were included in this analysis. There were significantly lower stroke events with rivaroxaban compared with VKA (Peto Odds Ratio (POR) 0.33, 95% confidence interval (CI) [0.11, 0.95]; P = 0.04), and significantly less thromboembolic events with rivaroxaban compared with VKA (POR 0.46, 95% CI [0.21, 0.97]; P = 0.04). Major and minor bleeding were equal with rivaroxaban versus VKA (Odds Ratio (OR) 0.92, 95% CI [0.62, 1.36]; P = 0.68) and (OR 0.81,95% CI [0.58, 1.11]; P = 0.19) respectively. Conclusion: The use of rivaroxaban in ablation and cardioversion of atrial fibrillation may be associated with decreased risk of stroke and thromboembolism with equal bleeding risk compared to VKA.
Limited information exists on the safety and efficacy of non-vitamin K oral anticoagulants (NOACs) in patients with pulmonary embolism (PE). The aim of this study is to evaluate the difference in the safety and efficacy of the NOACs in comparison to the standard treatment in patients presenting with deep vein thrombosis (DVT) and with PE using data from randomized controlled trials. MEDLINE and EMBASE databases were searched. Differences in the efficacy (recurrent VTE or death-related VTE) and in the safety (major bleeding) outcome were expressed as risk ratio (RR) with 95 % confidence intervals (95 % CI). Heterogeneity among the studies was assessed. Six studies (27,023 patients) were included. NOACs appeared to have a similar efficacy and safety compared to VKAs in patients presenting with PE and with DVT with a non-significant heterogeneity between the groups (efficacy: RR 0.90, 95 % CI 0.72, 1.13 in PE patients and 0.93, 95 % CI 0.75, 1.16 in DVT patients; [Formula: see text] 0.04, p = 0.84; safety: RR 0.49, 95 % CI 0.26, 0.95 in PE patients and 0.74 95 % CI 0.51, 1.06 in DVT; [Formula: see text] 1.10, p = 0.29). Our results suggest that the efficacy and safety of the NOACs compared to VKAs is similar between patients with PE and DVT.
Deep vein thrombosis (DVT) is a condition in which a clot forms in the deep veins, most commonly of the leg. It occurs in approximately one in 1000 people. If left untreated, the clot can travel up to the lungs and cause a potentially life-threatening pulmonary embolism (PE). Previously, a DVT was treated with the anticoagulants heparin and vitamin K antagonists. However, two forms of direct oral anticoagulants (DOACs) have been developed: oral direct thrombin inhibitors (DTIs) and oral factor Xa inhibitors, which have characteristics that may be favourable compared to conventional treatment, including oral administration, a predictable effect, lack of frequent monitoring or dose adjustment and few known drug interactions. DOACs are now commonly being used for treating
DVT:
recent guidelines recommended DOACs over conventional anticoagulants for both DVT and PE treatment. This Cochrane Review was first published in 2015. It was the first systematic review to measure the effectiveness and safety of these drugs in the treatment of DVT. This is an update of the 2015 review.
OBJECTIVES:
To assess the effectiveness and safety of oral DTIs and oral factor Xa inhibitors versus conventional anticoagulants for the long-term treatment of DVT.
SEARCH METHODS:
The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 1 March 2022.
SELECTION CRITERIA:
We included randomised controlled trials (RCTs) in which people with a DVT, confirmed by standard imaging techniques, were allocated to receive an oral DTI or an oral factor Xa inhibitor compared with conventional anticoagulation or compared with each other for the treatment of DVT.
DATA COLLECTION AND ANALYSIS:
We used standard Cochrane methods. Our primary outcomes were recurrent venous thromboembolism (VTE), recurrent DVT and PE. Secondary outcomes included all-cause mortality, major bleeding, post-thrombotic syndrome (PTS) and quality of life (QoL). We used GRADE to assess the certainty of evidence for each outcome.
MAIN RESULTS:
We identified 10 new studies with 2950 participants for this update. In total, we included 21 RCTs involving 30,895 participants. Three studies investigated oral DTIs (two dabigatran and one ximelagatran), 17 investigated oral factor Xa inhibitors (eight rivaroxaban, five apixaban and four edoxaban) and one three-arm trial investigated both a DTI (dabigatran) and factor Xa inhibitor (rivaroxaban). Overall, the studies were of good methodological quality. Meta-analysis comparing DTIs to conventional anticoagulation showed no clear difference in the rate of recurrent VTE (odds ratio (OR) 1.17, 95% confidence interval (CI) 0.83 to 1.65; 3 studies, 5994 participants; moderate-certainty evidence), recurrent DVT (OR 1.11, 95% CI 0.74 to 1.66; 3 studies, 5994 participants; moderate-certainty evidence), fatal PE (OR 1.32, 95% CI 0.29 to 6.02; 3 studies, 5994 participants; moderate-certainty evidence), non-fatal PE (OR 1.29, 95% CI 0.64 to 2.59; 3 studies, 5994 participants; moderate-certainty evidence) or all-cause mortality (OR 0.66, 95% CI 0.41 to 1.08; 1 study, 2489 participants; moderate-certainty evidence). DTIs reduced the rate of major bleeding (OR 0.58, 95% CI 0.38 to 0.89; 3 studies, 5994 participants; high-certainty evidence). For oral factor Xa inhibitors compared with conventional anticoagulation, meta-analysis demonstrated no clear difference in recurrent VTE (OR 0.85, 95% CI 0.71 to 1.01; 13 studies, 17,505 participants; moderate-certainty evidence), recurrent DVT (OR 0.70, 95% CI 0.49 to 1.01; 9 studies, 16,439 participants; moderate-certainty evidence), fatal PE (OR 1.18, 95% CI 0.69 to 2.02; 6 studies, 15,082 participants; moderate-certainty evidence), non-fatal PE (OR 0.93, 95% CI 0.68 to 1.27; 7 studies, 15,166 participants; moderate-certainty evidence) or all-cause mortality (OR 0.87, 95% CI 0.67 to 1.14; 9 studies, 10,770 participants; moderate-certainty evidence). Meta-analysis showed a reduced rate of major bleeding with oral factor Xa inhibitors compared with conventional anticoagulation (OR 0.63, 95% CI 0.45 to 0.89; 17 studies, 18,066 participants; high-certainty evidence).
AUTHORS' CONCLUSIONS:
The current review suggests that DOACs may be superior to conventional therapy in terms of safety (major bleeding), and are probably equivalent in terms of efficacy. There is probably little or no difference between DOACs and conventional anticoagulation in the prevention of recurrent VTE, recurrent DVT, pulmonary embolism and all-cause mortality. DOACs reduced the rate of major bleeding compared to conventional anticoagulation. The certainty of evidence was moderate or high.