Dear colleagues, I'm conducting a meta-analysis of studies evaluating adherence of HIV-positive drug users into AIDS treatment, therefore I'm looking for some advice and syntax suggestion for running the meta-regression using proportions, not the usual OR/RR frequently used on RCT studies. Have already searched already several handbooks, R-manuals, mailing lists, professors, but... not clue at all... Does anyone have already tried this? A colleague of mine recently published a similar study on JAMA, but he used OpenBUGS - a software I'm not familiar with... If there is any tip/suggestion for a possible syntax, could someone send me? I need to finish this paper before my PhD qualify, but I'm completely stuck... So, any tip will be more than welcome...I will really appreciate it!!! Thanks in advance and congrats on the amazing mailing-list. Bests from Rio de Janeiro, Brazil. Monica Monica Malta Researcher Oswaldo Cruz Foundation - FIOCRUZ Social Science Department - DCS/ENSP Rua Leopoldo Bulhoes, 1480 - room 905 Manguinhos Rio de Janeiro - RJ 21041-210 Brazil phone +55.21.2598-2715 fax +55.21.2598-2779 [[alternative HTML version deleted]]
OpenBUGS should be something related to Bayesian statistics. You may refer to Chapter 12 of Handbook http://cran.r-project.org/doc/vignettes/HSAUR/Ch_meta_analysis.pdf It talks about meta-regression. On 6/28/07, Monica Malta <momalta at cict.fiocruz.br> wrote:> Dear colleagues, > > I'm conducting a meta-analysis of studies evaluating adherence of HIV-positive drug users into AIDS treatment, therefore I'm looking for some advice and syntax suggestion for running the meta-regression using proportions, not the usual OR/RR frequently used on RCT studies. > > Have already searched already several handbooks, R-manuals, mailing lists, professors, but... not clue at all... > > Does anyone have already tried this? A colleague of mine recently published a similar study on JAMA, but he used OpenBUGS - a software I'm not familiar with... > > If there is any tip/suggestion for a possible syntax, could someone send me? I need to finish this paper before my PhD qualify, but I'm completely stuck... > > So, any tip will be more than welcome...I will really appreciate it!!! > > Thanks in advance and congrats on the amazing mailing-list. > > > > Bests from Rio de Janeiro, Brazil. > > Monica > > > > > > Monica Malta > Researcher > Oswaldo Cruz Foundation - FIOCRUZ > Social Science Department - DCS/ENSP > Rua Leopoldo Bulhoes, 1480 - room 905 > Manguinhos > Rio de Janeiro - RJ 21041-210 > Brazil > phone +55.21.2598-2715 > fax +55.21.2598-2779 > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >-- "The scientists of today think deeply instead of clearly. One must be sane to think clearly, but one can think deeply and be quite insane." Nikola Tesla http://www.macgrass.com
Monica Malta wrote:> Dear colleagues, > > I'm conducting a meta-analysis of studies evaluating adherence of HIV-positive drug users into AIDS treatment, therefore I'm looking for some advice and syntax suggestion for running the meta-regression using proportions, not the usual OR/RR frequently used on RCT studies. > > Have already searched already several handbooks, R-manuals, mailing lists, professors, but... not clue at all... > > Does anyone have already tried this? A colleague of mine recently published a similar study on JAMA, but he used OpenBUGS - a software I'm not familiar with... > > If there is any tip/suggestion for a possible syntax, could someone send me? I need to finish this paper before my PhD qualify, but I'm completely stuck... > > So, any tip will be more than welcome...I will really appreciate it!!! > > Thanks in advance and congrats on the amazing mailing-list.Specifying adherence as the "effect size", if you can also specify a sampling variance perhaps you can use a tool like mima (http://www.wvbauer.com/downloads/mima_tutorial.pdf). For example, working with logits rather than proportions directly, consider the following example data:> dfntot nadhere mod prop logit se 1 100 76 0 0.7600000 -1.1526795 0.2341463 2 125 98 0 0.7840000 -1.2891306 0.2173501 3 50 37 0 0.7400000 -1.0459686 0.3224127 4 200 159 0 0.7950000 -1.3553321 0.1751557 5 150 114 0 0.7600000 -1.1526795 0.1911796 6 80 56 1 0.7000000 -0.8472979 0.2439749 7 160 113 1 0.7062500 -0.8772402 0.1735688 8 200 130 1 0.6500000 -0.6190392 0.1482498 9 120 75 1 0.6250000 -0.5108256 0.1885618 10 105 78 1 0.7428571 -1.0608720 0.2232879 Then do the meta-regression as follows:> source("http://www.wvbauer.com/downloads/mima.ssc")> with(df, mima(yi=logit, vi=se, mods=mod))Estimate of (Residual) Heterogeneity: 0 Test for (Residual) Heterogeneity: QE = 1.2419 df = 8 p-value = 0.9962 Parameter Estimates: [,1] intrcpt -1.2161 mods 0.4520 Variance-Covariance Matrix of Parameter Estimates: intrcpt mods intrcpt 0.0436 -0.0436 mods -0.0436 0.0815 Omnibus Test of all Moderators: QME = 2.5058 df = 1 p-value = 0.1134 Individual Moderator Tests: estimate SE zval pval CI_L CI_U intrcpt -1.2161 0.2089 -5.8213 0.0000 -1.6256 -0.8067 mods 0.4520 0.2856 1.5830 0.1134 -0.1077 1.0117> Bests from Rio de Janeiro, Brazil. > > Monica > > Monica Malta > Researcher > Oswaldo Cruz Foundation - FIOCRUZ > Social Science Department - DCS/ENSP > Rua Leopoldo Bulhoes, 1480 - room 905 > Manguinhos > Rio de Janeiro - RJ 21041-210 > Brazil > phone +55.21.2598-2715 > fax +55.21.2598-2779 > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.-- Chuck Cleland, Ph.D. NDRI, Inc. 71 West 23rd Street, 8th floor New York, NY 10010 tel: (212) 845-4495 (Tu, Th) tel: (732) 512-0171 (M, W, F) fax: (917) 438-0894