# How to combine slopes from two separate analysis with same variables? [closed]

I am wondering if there is a way to combine slopes/results from two separate linear regression analysis in R. I am not sure if meta-regression applies here or is there a package in R that will help me do this?

Thanks!!

linreg1 <- lm(BMI ~ PA + Stress, data=data1)
linreg2 <- lm(BMI ~ PA + Stress, data=data2)


• Please explain how the two datasets are related and what their sizes are (if known). – whuber May 3 at 20:49
• The two dataset/cohorts have a similar sample (young adults), with sample 1 (n=400) and sample 2 (n=530), but since the ethnicity is different, it was recommended to run separate MLR on the two cohorts and then meta-analyze the results. – user13514792 May 4 at 13:23
• OK. That raises an important question: in what sense do you want to "combine" the results, when they reflect potentially different fits for different ethnicities? – whuber May 4 at 14:12
• If you want to go down the meta-analysis route then since you have multiple parameters in each model you need to investigate multi-level meta-analysis. You will need the variance covariance matrix of the estimates but since you have the data you can easily generate them. But as @whuber suggests it is a bit hard to see the point of averaging them if you believe they are different. – mdewey 2 days ago