ABSTRACT
Background@#and Purpose New studies have shown that endovascular thrombectomy (EVT) is safe and effective for acute ischemic stroke (AIS) patients with large ischemic areas. The aim of our study is to conduct a living systematic review and meta-analysis of randomized trials comparing EVT versus medical management only. @*Methods@#We searched MEDLINE, Embase, and the Cochrane Library to identify randomized controlled trials (RCTs) comparing EVT versus medical management alone in AIS patients with large ischemic regions. We conducted our meta-analysis using fixed-effect models to compare functional independence, mortality, and symptomatic intracranial hemorrhage (sICH) between EVT and standard medical management only. We assessed the risk of bias using the Cochrane risk-of-bias tool and the certainty of evidence for each outcome using the Grading of Recommendations, Assessment, Development, and Evaluations approach. @*Results@#Of 14,513 citations, we included 3 RCTs with a total of 1,010 participants. We found low-certainty evidence of possibly a large increase in the proportion of patients with functional independence (risk difference [RD] 30.3%, 95% CI 15.0% to 52.3%), low-certainty evidence of possibly a small non-significant decrease in mortality (RD -0.7%, 95% CI -3.8% to 3.5%), and low-certainty evidence of possibly a small non-significant increase in sICH (RD 3.1%, 95% CI -0.3% to 9.8%) for AIS patients with large infarcts who underwent EVT compared to medical management only. @*Conclusion@#Low-certainty evidence shows that there is possibly a large increase in functional independence, a small non-significant decrease in mortality, and a small non-significant increase in sICH amongst AIS patients with large infarcts undergoing EVT compared to medical management only.
ABSTRACT
In the previous two parts of educational manuscript series in Emergency, we explained some screening characteristics of diagnostic tests including accuracy, sensitivity, specificity, and positive and negative predicative values [1, 2]. In the 3rd part we aimed to explain positive and negative likelihood ratio [LR] as one of the most reliable performance measures of a diagnostic test [3]. To better understand this characteristic of a test, it is first necessary to fully understand the concept of sensitivity and specificity. So we strongly advise you to review the 1st part of this series again [1, 2]. In short, the likelihood ratios are about the percentage of people with and without a disease but having the same test result [4]. The prevalence of a disease can directly influence screening characteristics of a diagnostic test, especially its sensitivity and specificity. Trying to eliminate this effect, LR was developed. Pre-test probability of a disease multiplied by positive or negative LR can estimate post-test probability. Therefore, LR is the most important characteristic of a test to rule out or rule in a diagnosis. A positive likelihood ratio > 1 means higher probability of the disease to be present in a patient with a positive test. The further from 1, either higher or lower, the stronger the evidence to rule in or rule out the disease, respectively [5]. It is obvious that tests with LR close to one are less practical. On the other hand, LR further from one will have more value for application in medicine. Usually tests with LR < 0.1 or > 10 are considered suitable for implication in routine practice
ABSTRACT
In volume 3, number 2, pages 48-49, we explained some screening characteristics of a diagnostic test in an educational manuscript entitled "Simple definition and calculation of accuracy, sensitivity and specificity" [1]. The present article was aimed to review other screening performance characteristics including positive and negative predictive values [PPV and NPV]. PPV and NPV are true positive and true negative results of a diagnostic test, respectively [2]. In other words, if a subject receives a certain diagnosis by a test, predictive values describe how likely it is for the diagnosis to be correct