Metaanalyses have become an essential tool in synthesizing evidence on clinical and epidemiological questions derived from a multitude of similar studies assessing the particular issue. I want to do a proportion metaanalysis by taking the proportion of outcome a from the intervention x and the proportion of outcome a from the intervention y and pooling these proportions between. In the second metaanalysis, the pooled percentage of cured women. There are various models that can be used to pool the proportions. In addition to pooling effect sizes, meta analysis can also be used to estimate disease frequencies, such as incidence and prevalence. Metaanalysis of proportions is a little bit different than other types of metaanalysis it includes studies that do not use control groups. In order to run a metaanalysis of diagnostic odds ratios simply use the odds ratio metaanalysis. The outcome of interest in each study is represented by a proportion percentage. I have a question regarding meta analysis on pooled proportions e. Appropriate and accessible statistical software is needed to produce the. Metaanalysis of proportions is observational and noncomparative in nature. Before you start collecting the actual data for the meta analysis, decide which statistical software package will be used to analyze the data. The only thing which differs in various synthesizing methods is the calculation of weights and how these weights.
This evidence is in line with reports from several studies that revealed a proportion of secondline hiv treatment failure as high as 25% 32, 6569. Openmeta analyst, an opensource software for meta analysis, and comprehensive meta analysis software were used for the statistical analysis. Will mplus output such a pooled matrix, given summary correlation data. In addition to pooling effect sizes, metaanalysis can also be used to estimate disease frequencies, such. Inclusion of zero total event trials in metaanalyses. The pharyngeal carriage of haemophilus influenzae among. For a meta analysis, i have pooled single proportions complication rates and reoperations of 5 treatment methods separately using a random effects model. Undernutrition among ethiopian adults living with hiv. This evidence is in line with reports from several studies that revealed a. We have found many books and articles on meta analysis. Brief overview of methods and general hints description r package meta is a userfriendly general package providing standard methods for meta analysis. The simulation was designed to produce 200000 pooled proportions for each. In the second metaanalysis, the pooled percentage of cured women was 94%.
The preventable proportion of healthcareassociated. In this article we present methods for the meta analysis of prevalence. Secondline hiv treatment failure in subsaharan africa. In this situation, metaanalysis is biased, although it remains. A metaanalysis integrates the quantitative findings proportions from. Meta analyses have become an essential tool in synthesizing evidence on clinical and epidemiological questions derived from a multitude of similar studies assessing the particular issue. Apr 30, 2015 there are two important caveats to this recommendation. For this workshop, we will be using the meta analysis commands that were introduced in stata 16. Methods of estimating the pooled effect size under meta. Stack overflow for teams is a private, secure spot for you and your coworkers to find and share information. A systematic literature search was conducted via the following databases. The goals of meta analysis may be summarized as follows. In this article we present methods for the metaanalysis of prevalence. Random effects with pooled estimate of 2 171 the proportion of variance explained 179 mixedeffects model 183 obtaining an overall effect.
How can i perform pooled prevalence using r for metaanalysis. Pooling, metaanalysis, and the evaluation of drug safety. A 95% confidence interval was used in assessing the individual study proportion and pooled effects. Metaregression analyses for the sensitivity of chest ct revealed that the distribution of disease severity, the proportion of patients with comorbidities, and the. Based on these findings, we see poisson regression with random intervention effects as a useful method for conducting a meta analysis of incidence rate data, especially when the data contains structural zeros.
Yes it is perfectly possible to do this either in stata or in r. Look at the help file for the command that you will be using. However, at the moment the effect sizes have to be entered into the software beforehand jasp cannot calculate this for you. The classic metaanalysis model with logit transformed proportions is used by setting argument method. Metaanalysis of incidence rate data in the presence of. Metaanalysis of proportions versus simple pooling of data meta. Brief overview of methods and general hints description r package meta is a userfriendly general package providing standard methods for metaanalysis. The outcome of interest in each study is represented by a proportionpercentage. The authors performed a metaanalysis and individual data pooled analysis of casecontrol studies that examined the association between c677t and a1298c polymorphisms the former being associated. Metaprop is a statistical program implemented to perform meta analyses of proportions in stata. The pooled effect under metaanalysis is weighted average of the study level effect sizes. The goals of metaanalysis may be summarized as follows. I need to do meta analysis of these proportions in stata.
A list of software for metaanalysis in r is available in. Level of selfcare practice among diabetic patients in. The analysis n 786 demonstrated a net proportion metaanalysis pooled rate of 76. Ive been reading cheungs work on metaanalytic sem, which pools correlation matrices via multiplegroup analysis. In that way, the software automatically asks you to enter the standard error of. In this situation, meta analysis is biased, although it remains the best method to summarize the data. The authors performed a meta analysis and individual data pooled analysis of casecontrol studies that examined the association between c677t and a1298c polymorphisms the former being associated with low folate serum levels and gastric cancer meta analyses. Aug 27, 2017 meta analysis of proportions is a little bit different than other types of meta analysis it includes studies that do not use control groups. Mplus discussion pooled correlation matrix for sem meta. Metaanalysis of incidence rate data in the presence of zero. To realize a pooled analysis in order to calculate a summary effect a weighted proportion to calculate heterogeneity across the studies.
I have to to synthesise this data in a meta analysis, and i recently attended a course where i learnt about using the metan code from the online stata journal to conduct meta analysis of rd, rr and or data. N2 the conventional random effects model for metaanalysis of proportions approximates withinstudy variation using a normal. Appropriate and accessible statistical software is needed to produce the summary statistic of interest. Since i use r i offer a few hints to get you going. Based on these findings, we see poisson regression with random.
Several electronic databases were searched to identify the studies reporting the pathogens of pla. I have a question regarding metaanalysis on pooled proportions e. This data was pooled using a random effects model with the dersimonianlaird method calculated with metaanalyst software version beta 3. The program lists the proportions expressed as a percentage, with their 95% ci, found in the individual studies included in the meta analysis. In metafor, this can be done by computing the exact 95% cis using the binom. Thus, while it is possible to conduct a meta analysis using, for example five studies, a meta analysis with more studies than this will provide more stable estimates for all parameters. Metaanalysis of proportions of rare eventsa comparison of. This is the first metaanalysis of the pooled prevalence of insomnia in the general population of china.
Meta analysis is a method to obtain a weighted average of results from various studies. Hannah rothstein july 1, 2007 c m borenstein, l hedges, h rothstein 2007. In this metaanalysis, the pooled estimate of proportion for secondline hiv treatment failure was 15. Meta and pooled analyses of the methylenetetrahydrofolate. First, our simulations show that the accuracy of the pooled irr improves as the number of studies increases. Statsdirect first transforms proportions via the freemantukey double arcsine method murray et al.
The above disparities could be due to the difference in the study area since our study conducted at the national level and gender, which would be highly. To conduct a meta analysis in jasp, be sure to check our their guide. Dec 01, 2014 a metaanalysis was performed with the pooled estimate proportion of patients that achieved clinical remission. Fecal microbiota transplantation as therapy for inflammatory.
Metaanalysis of prevalence journal of epidemiology. Apr 16, 2020 for example, a meta analysis study conducted in other ssa countries reported that the pooled proportion of hivrelated undernutrition among hiv infected women was 10. Comparing pooled propotions for a metaanalysis cross validated. The data i have to synthesise is a simple proportionpercentage those with distress as a proportion of the total diabetes sample. We are planning for a metaanalysis which involves pooling of prevalence data. Given the absence of a significant treatment effect among trials with at least 1 event, the inclusion of the zero total event trials decreases the confidence intervals of the pooled effect estimates but not the estimates themselves. The default metaanalysis methods of metaanalysis software. Bero l, montgomery p, robinson k, pigott t, krause. The pooled effect under meta analysis is weighted average of the study level effect sizes. Note, you should use r function metabin to compare proportions of pairwise comparisons instead of using metaprop for each treatment arm separately which will break randomisation in randomised controlled trials. It seems that my software stata cannot do the mantel haenszel method for meta analysis of proportions i. It is the proportion of times the 95% confidence interval contains the population parameter. Metaanalysis michaelborenstein biostat, inc, new jersey, usa. Learn more using metafor or meta for meta analysis of proportions.
The sample size n is known and is different for each study. Metaanalysis handles randomized trials with no outcome events in both treatment and control arms inconsistently, including them when risk difference rd is the effect measure but excluding them. Sample publications and presentations pertaining to meta analyses of epidemiologic studies. I want to do a proportion metaanalysis by taking the proportion of outcome a from the. There are two important caveats to this recommendation. Michael borenstein larry hedges hannah rothstein metaanalysis. Distribution of common pathogens in patients with pyogenic. I have to to synthesise this data in a metaanalysis, and i recently attended. The pooled proportion with 95% ci is given both for the fixed effects model and the random effects model. This video tutorial is an original work i produced. How to conduct a metaanalysis of proportions in r youtube.
Metaanalysis of hazard ratios statistical software. I found the comprehensive metaanalysis software program to be extremely user friendly, providing instant computational data from the simplest to the most complex statistical problems, a versatile. The randomeffects metaanalysis model was employed to estimate the pooled proportion of good diabetic selfcare practices. All the three methods consider different weights for the calculation of pooled effect. Now i would like to compare the 4 pooled treatment modalities with the pooled golden standard separately by using the chisquared test 4 times. The historical roots of metaanalysis can be traced back to 17th century studies of astronomy, while a paper published in 1904 by the statistician karl pearson in the british medical journal which. Pdf how to conduct a metaanalysis of proportions in r. Mar 19, 2002 a limitation to meta analysis is found when data are very sparse, for example, when a high proportion of zero events exist in trials. Data synthesis was performed using stata version 11. We included 35 studies with 11,103 participants in this meta. The level used to calculate confidence intervals for pooled estimates.
The data i have to synthesise is a simple proportion percentage those with distress as a proportion of the total diabetes sample. The reason why people choose r over other software to conduct metaanalyses is pri. T1 metaanalysis of proportions of rare eventsa comparison of exact likelihood methods with robust variance estimation. When studies are not homogenous, the xed and random e ects approaches. The only thing which differs in various synthesizing methods is the calculation of weights and how these weights incorporate between study heterogeneity. There are various models that can be used to pool the proportions, so i am not sure which one you are looking for, but a binomialnormal model essentially a randomeffects logistic regression model is often a good choice.
This function provides methods for fixed effect and random effects meta analysis of single proportions to calculate an overall proportion. Metaanalysis of proportions of rare eventsa comparison. You can do such analysis on open metaanalyst software. Metaanalysis is a method to obtain a weighted average of results from various studies.
A pooled analysis is similar to a traditional metaanalysis, except that participantlevel data from multiple studies are combined and analyzed as a single dataset. For a metaanalysis, i have pooled single proportions complication rates and reoperations of 5 treatment methods separately using a random effects model. I have been recearching the available literature for some time now and i am still unsure if i am doing this correctly or not. Out of these, eight studies were finally included for metaanalysis. Results of the metaanalysis indicated that the pooled carriage proportion of h. Diagnostic performance of ct and reverse transcriptase. The meta analysis function of jasp is based on the aforementioned metafor r package.
With this, the rate of secondline therapy failure among hiv. For example, a metaanalysis study conducted in other ssa countries reported that the pooled proportion of hivrelated undernutrition among hiv infected women was 10. Metaanalysis of a very low proportion through adjusted wald. A pooled analysis is similar to a traditional meta analysis, except that participantlevel data from multiple studies are combined and analyzed as a single dataset. We discuss the logit and double arcsine transformations to stabilise the variance. The program lists the proportions expressed as a percentage, with their 95% ci, found in the individual studies included in the metaanalysis. The historical roots of meta analysis can be traced back to 17th century studies of astronomy, while a paper published in 1904 by the statistician karl pearson in the british medical journal which collated data from several studies of typhoid inoculation is seen as the first time a meta analytic approach was used to aggregate the outcomes of multiple clinical studies.