meta-analysis

  1. 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...
  2. 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...
  3. 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...
  4. 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...
  5. 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...
  6. 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...
  7. 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...
  8. 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...
  9. 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...
  10. 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...
  11. 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...
  12. 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...
  13. A

    Confusion with writing command for meta-analysis in STATA

    I am a beginner in STATA and do not understand how to write syntax for the meta-analysis command using the variables in my research study. Any help would be so greatly appreciated! My study: I am trying to use meta-analysis to investigate how several different variables impact prevalence...
  14. C

    Estimating the variance of a computation from descriptive statistics

    Hello, I am a Ph.D. candidate in the behavioural sciences and I am a bit at a loss with respect to finding a solution to the problem to follow: I have the means and standard deviations of three time points in a sample of twenty people. Mean (SD) 10.3 (2.4) 9.2 (1.3) 9.5 (1.8) I...
  15. G

    Meta-Regression

    Hi! I just want to ask if there are people familiar with Meta-Regression/Meta-Regression Analyses (MRA). I'm planning to have it as an Undergraduate Thesis but I'm having trouble about resources, references and the software to used. Is there someone/somebody familiar with it? I need answers...
  16. J

    Calculate effect size from regression estimates for meta-analysis

    Hi, I really hope someone can help me, I'm a bit stuck.. I'm running a meta-analysis looking at childhood predictors of personality disorders, so I'm pooling effect sizes of published longitudinal studies looking at this relationship. I need effect size data for all studies I want to...
  17. E

    Standard deviation of the mean difference out of Pre/Post Test Descriptive Statistics

    I have several RCT pre/post intervention studies that I am calculating Hedge's g for. All of the studies report the difference of mean and difference of standard deviation between pre/post for each group except one. I know how to calculate the difference of mean [= Mean(post)-Mean(pre)], but...
  18. G

    How to use a meta-analysis to assess the equivalence of two different procedures?

    I'm making a comparison of two surgical procedures, and I want to know how I can analyze the data I have for a meta-analysis. The overall surgical procedure is the same, but some authors choose to modify the procedure a bit. So basically I have a large number of studies with the standard...
  19. S

    Interpretation of correlation coefficient

    Hello, I am working on a meta-analysis with the program R. Here I am investigating the relationship between the dependent variable "participation in Lobbying" (results = yes or no) and the independent variable "company size" (result = value of assets). The result I got is an Fisher's...
  20. M

    Convert odds ratios and beta coefficients to a comparable effect size

    Dear all, First a short introduction to my study/review/meta-analysis. The purpose of my study is to systematically review longitudinal evidence on the association between psychosocial work characteristics (i.e. job demands, job control, social support) and sleep, since cross-sectional...