[R-meta] Effect Sizes From Pretest-Posttest-Control Group Designs and effect sizes from Pretest-Posttest designs

[Viechtbauer, Wolfgang (SP)]

Dear Yingkai,

I don't think there is a single answer here. Of course one can do this -- whether one should in any particular case depends on the circumstances. And not sure why combining effect sizes from pretest-posttest-control group designs and effect sizes from between-group designs is out of the question. In any case, a canonical reference here is:

Morris, S. B., & DeShon, R. P. (2002). Combining effect size estimates in meta-analysis with repeated measures and independent-groups designs. Psychological Methods, 7(1), 105-125. https://doi.org/10.1037/1082-989x.7.1.105

Best,
Wolfgang

>-----Original Message-----
>From: Yingkai [mailto:yykjiyisuipian using gmail.com]
>Sent: Monday, 13 December, 2021 15:08
>To: r-sig-meta-analysis using r-project.org
>Cc: Viechtbauer, Wolfgang (SP)
>Subject: Effect Sizes From Pretest-Posttest-Control Group Designs and effect
>sizes from Pretest-Posttest designs
>
>Hi Dr. Wolfgang and all,
>    I am wondering whether one can combine effect sizes from pretest-posttest-
>control Group designs and effect sizes from pretest-posttest designs(no control
>group) in a meta-analysis?
>I know that one should not combine effect sizes from pretest-posttest-control
>Group designs and effect sizes from between-group designs in a meta-analysis.
>
>Best,
>--
>Yingkai, Associate Professor.
>Southwest University, ChongQing, CHINA.