pre post correlation comprehensive meta analysis

When using the quasi-indirect approach (‘then-test’), patients are asked after an intervention to rate their statuses both before the intervention as well as at the time of the enquiry. With indirect measures of change, the patients’ status is assessed at different time points and differences between them are calculated (measured change). Direct measurement of change (transition ratings) requires asking a patient directly about his judgment about the change he has experienced (reported change). You'll find a technical report about these, written for AHRQ, here.Ĭheck here to see a group on this website meant for beginner meta-analysts (or those who want the big picture).Different approaches have been developed for measuring change. Tania Huedo-Medina and I recently finished a Monte Carlo simulation that offers best-practice guidelines for these situations, and in the one you mention a strategy Becker (1988) offered will work. Usually our group will correct for differences that appear at baseline, so yes, your instructions sound too simple.

And there is a spreadsheet here on this website that makes a lot of these comparisons. The chapter I mention offers equations for these comparisons. I discuss these issues in a recent chapter that I will email you. It is possible to meta-analyze studies with pre-post designs (see Becker, 1988). Same answer: Do sensitivity analyses to see if the patterns differ between the types of studies. If there are differences, they may be difficult to explain but at least you have this bit of knowledge to offer others who study the same issues. Yes, but usually you will want to conduct a moderator analysis to see if results replicate on the different measures. I have at this stage no-one available in person to offer me support so any virtual-support is greatly appreciated! and n - don't I need some information about baseline too?Īs you can see -I'm very new and confused and would be really grateful if someone could help me out and point me in the direction of a good beginners guide for this. I'm trying to learn about the types of comparisons I can use in meta-analysis with newbie questions likeĪ) can I do meta-analysis where the outcome measures are different measures but of the same construct?ī) can you mix up study types in a meta-analysis / is it even possible to meta-analyse pre-post designs?Ĭ) when you have RCT with pre and follow-up data - what information do you use to calculate an effect size - in same cases I have the ANOVA F statistic in others just means and standard deviations of the groups - are they ok to use?ĭ) In controlled studies, I've been told to extract mean outcome score at follow-up for the treatment and control group, with s.d.

I'm new to meta-analysis but slightly older to systematic literature reviewing.

Pre post correlation comprehensive meta analysis