meta-analysis

  1. B

    Effect Size - Cohen's D calculation

    I had a question about how to calculate Cohen's D a particular situation for my meta-analysis. I am a first year grad student, so my familiarity with statistics is somewhat limited! The study design - participants are assigned to one of two groups (parallel design), but not a true RCT because...
  2. A

    Meta-analysis for Pre vs Post (Which SD to use)

    Hello everyone, I have extracted data from longitudinal studies that have collected data on pre and post time points. All studies have same time period. So I have got N_pre Mean_Pre SD_Pre N_post Mean_Post SD_Post In order to compute the standardised or unstandardised Mean...
  3. K

    Use treatment effect as input for meta-analysis, not 2 groups

    Hey, I'm new to R and currently trying to teach myself how to use it with various guides. Problem is, none of the guides cover the scenario I'm dealing with, they all assume that for a meta-analysis you have outcome data for both the control and treatment groups. I would like to use the...
  4. S

    meta-analysis vs. random effect combined analysis

    I have data from 200 similar studies, all measuring the same effect of a continuous independent variable on the same continuous response. I say similar because the designs are different (split plot vs. rcbd) and the levels of the independent variable is not the same across all studies. I have...
  5. C

    Meta-analysis - Can I investigate mediation effects for the effectiveness of training

    Hello everyone, I am currently working on my Master thesis on moderators and mediators for the effectiveness of cross-cultural training (CCT). I am actually writing a literature review, but want to end my thesis by judging to what extent the included studies could also be compared...
  6. A

    Adjustment for correlated data in meta-anlaysis

    Hi, I'm completing a systematic review and performing meta-anlaysis forest plots. The research question related to the finding of risk factors for a complication of diabetes. There are therefore many different risk factors and often there are only three papers with similar...
  7. B

    [STATA - gsem] Multilevel Structural Equation Model - Meta Analysis

    Hello, I am quite familiar with mixed effects (multilevel models) in meta analyses. Now, I want to do a mixed effects (multilevel) meta analysis structural equation model (MASEM) with STATA and the gsem package because my data format is long. My data look like: `id studyId...
  8. V

    Meta-analysis of diagnostic test using MCMC

    Hi. Is there some good hands-on tutorial about running MCMC analysis for the meta-analysis of diagnostic tests? Is it inbuilt STATA Bayesian analysis is sufficient for this task or is necessary to install some additional patch? Thanks!
  9. D

    Using Pre-Post data in a meta-analysis

    Hello, I am trying to figure out the best way to calculate an effect size for a single-group design when I do not know the pair-wise correlation or standard deviation for the difference scores. I have received mixed messages as to whether or not I can use the formula for independent measures...
  10. A

    Meta-analysis to compare 3 randomized control trials?

    I'm proposing to evaluate an outcome in three completed randomized controlled trials. The primary goal is to analyze a new outcome in each data set separately (i.e., 3 separate papers). A secondary aim is to compare across the three trials to see which intervention type was most effective...
  11. G

    Multiple intervention groups for meta-analysis help

    Hi everybody I'm conducting a meta-analysis, and some papers have 2 or 3 intervention groups in addition to the control. I read that I should possibly split the control group equally and examine as separate outcomes. Also, would it be as simple as splitting the control equally, and...
  12. G

    percentages or adjusted odds ratio on revman help

    Hi Hi, I'm new to meta-analyses and revman and would really appreciate your help! I have data from an article I wish to add to revman. They have given an adjusted odds ratio, percentages of the event, and the total number of participants in each group. I thought that if I had the...
  13. Y

    Coding Group Equivalency on Pre-Treatment Measures for Meta-Analysis?

    Hello- I am constructing a code book for a meta-analysis. I only want to include evaluations where program and comparison groups were reasonably well matched on pre-existing differences in key variables, such as age, prior educational achievement, etc. Any recommendations on what statistic to...
  14. A

    Which method is best for synthesising effectiveness data of interventions?

    Hello everyone, I was wondering if someone might be able to point me in the right direction... I want to combine the findings of several different primary research studies to identify how effective different kinds of interventions are at increasing physical activity levels. At first, I...
  15. R

    Doubt about "effect size": standardized mean difference

    Hi everybody. I have a question about how to interprete a standardized mean difference. I was reading a meta-analysis in which the authors calculate the SMD, because they evaluate continuos variables (a linear measure in mm), of the same outcome, assessed in different ways. The reported SMD...
  16. S

    meta-analysis combined p-value from different tests

    I want to examine whether the students of School A have done significantly better than the students of School B in science subjects. In Math, School A does moderately better (p-value: 0.06) than school B. We observe similar and consistent results for physics (p-value:0.09) and chemistry...
  17. S

    Meta-analysis: How should one handle non-significant studies containing no raw data?

    Let's say that I'm conducting a meta-analysis, looking at the performance of group A and group B with respect to a certain construct. Now, some of the studies that I'll come across will report that no statistical differences could be found between the two groups but no exact test statistics...
  18. J

    Meta-analysis - can I combine/use these studies?

    Hi! I'm trying to set up a meta-analysis with my thesis partner and we ran into trouble which our supervisor isn't able to solve. So I figured I'd turn to the internet :) Googling hasn't helped me much, so now I'm on a forum. In our research, we are looking for the effect of...
  19. A

    metareg - need help calculating hedges q in STATA

    Novice STATA user here... I ran a meta-regression to analyze how prevalence rates of personality disorders vary according to differences in study design (e.g., gender of participants m/f). In order to see if there is enough variability within each of my dependent variables (10 different...
  20. G

    Use of different outputs in a meta-analysis?

    I'm interested in performing a meta-analysis of instrumental variable analyses from a handful of different studies, asking for the same set of model results from all study investigators. As my access is limited to summarized data, i'd like the study investigators to send their ivregress output...