# How to conduct a meta-analysis on studies that report results variously as odds ratios, hazards ratios, or rate ratios?

I'm doing a meta-analysis of some studies that report results variously as odds ratios, hazards ratios or rate ratios (all with confidence intervals). Is there any way to combine these together/convert between them so that I can do a meta-analysis of all the studies?

3. Rate Ratios and HRs: These you might be more capable of getting away with. If the rate ratio is the ratio of two rates calculated as  cases/person-time, then that is actually a hazard ratio estimate as well. It's just a hazard ratio made under the assumption of both proportional and constant hazards. You can convert those directly to an HR, but again, I'd look at study heterogenity by which measure it reported, as rate ratios and a HR that came out of something like a Cox model are performed under different assumptions.