meta-analysis

  1. N

    mean rank to mean + sd ?

    Hi everyone, We are students trying meta-analysis for the first time using revman software (of cochrane). For one of our study we are stuck because we only have the mean rank and we don't know how to convert the mean rank into mean and standard deviation to obtain our forest plot. If someone...
  2. C

    comparing by-subject with mixed-designs

    Hi, I know a common critique for meta-analysis is the comparing apples and pears argument. I am still trying to include as many different study methods (the method will be a factor), but I am not sure if it statistically makes sense if I also include mixed-design studies when most others are...
  3. F

    Running a moderation analysis in a meta-analysis using k<10 (7)

    Hello, For my master thesis, I am looking at the moderating effect of culture (Hofstede's dimensions) on the relationship between career exploration and it's antecedents using a meta-analysis (Never conducted one before, still familiarizing myself with it). The problem is that one of the...
  4. T

    Multiple Meta-Regression in Stata Help

    I'm new to meta-analysis and to Stata. I understand how to use the user interface to insert multiple covariates into a meta-regression. However, I am not sure how to interpret the output and to make sure that the software has controlled for multiplicity and covariate correlation - so that I...
  5. R

    Looking for the appropriate stat test

    I am attempting to do a meta-analysis to understand a treatment effect . There are groups across many studies which have treatments A and B and a control group without any treatment. In other studies, there are groups with just treatment A and control groups. I am trying to understand what the...
  6. F

    Questions about trial sequential analysis for non-randomized control studies (non-RCTs)

    May I ask a question on the trial sequential analysis (TSA)? It is a method of cumulative meta-analysis. Could we pooled adjusted risk ratios (aRR) in trial sequential analysis, especially for observational studies in which there are obvious differences between crude RR and adjusted RR? Now, I...
  7. E

    OR meta-analysis using R

    Hi! I have currently been using MedCalc for Odds Ratio meta-analysis. For both intervention and control groups is required the following data input: number of positive cases and number of total cases. The problem is, sometimes studies report Odds Ratios with CI:s, without primary data. ORs...
  8. T

    Change of statistical significance when excluding heterogenic studies?

    Hi all, I have performed a meta-analysis and found a certain pooled effect with 95% CI that was not statistically significant (p>0.05). Consequently, I have done a sensitivity analysis for which I have excluded studies that contributed most to heterogeneity. In order to do so I used the...
  9. S

    Likelihood ratio or wald test for meta-analysis

    Hi there! This is my first time posting but I've always been a frequent lurker on previous posts that have been super helpful, so apologies if I'm not following any appropriate etiquette. I am working on an RNA sequencing project and looking have different outputs, which provides either a...
  10. M

    Individual results in forest plot meta-analysis

    Dear all, In this meta-analysis (https://www.ncbi.nlm.nih.gov/pubmed/30475963) it seems that for instance in figure 2 for lean body mass improvements individual studies did not find significant better results with protein supplementation compared to no protein supplementation (since the...
  11. N

    Meta-analysis and longitudinal studies with baseline differences across two groups.

    I have a question on what meta-analysis is best when aggregating means using non-randomized longitudinal data with a control group that significantly differs from the active group at baseline. The outcome in question is depression, and the question is whether depression scores soar or fall in...
  12. L

    Meta-analysis with dependent samples

    Dear Forum, for my thesis I would like to conduct a meta-analysis with the aim to summarize the findings about the effectiveness of a political measure. The corresponding studies compare countries in which the measure was implemented with countries in which it was not implemented and calculate...
  13. B

    Heterogeneity calculation based on odds ratios and confidence intervals

    Hi, I wonder if you might be able to help with testing for heterogeneity (Cochran's q or I-squred) in meta-analysing genotypic odds ratios in two groups from two different genetic associations studies of the same phenotype. (This question pertains to genetics, but the principle, I believe, is...
  14. P

    Trial sequential analysis of noninferiority randomized control trials

    Hello, anyone out there familiar with Trial Sequential Analysis (TSA) software developed by Copenhagen Trial Unit? The free software is available at: http://www.ctu.dk/tsa/downloads.aspx Manual is available here: http://www.ctu.dk/tsa/files/tsa_manual.pdf Summary of my questions up here: 1. How...
  15. L

    Converting spearmans r to fishers z for meta analysis ; Correcting for range in meta analysis

    Hi all I am conducting a meta analysis of pearsons r correlations but I have a study with a spearmans rank correlation. I was converting the pearsons correlations into fishers z scores to conduct the meta analysis , then to be converted back into correlations, but I am wondering if I am able to...
  16. J

    Meta-analysis using revman

    I was wondering if someone can help me with a meta-analysis using revman 5.3. I would like to switch from quadas to quadas2 but this link seems to be missing from the General tab. Has anyone had the same problem?
  17. A

    What statistical techniques to apply when comparing cronbach's alpha in a Meta-analysis

    I am doing a meta-analysis in which I am comparing 3 outcomes measures across multiple studies: (1) Cronbach's alpha (2) Kappa coefficient or Interclass correlation coefficient (depending on which study chose what measure) (3) Spearman Rank Correlation coefficient or Pearson correlation...
  18. 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...
  19. 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...
  20. 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...