[R-meta] how do i get the ri for a meta analysis pre post test

[Viechtbauer, Wolfgang (SP)]

Hi Lorenzo,

You have to extract ri from the articles - it is not something you calculate. If you don't know the pre- to post-test correlation, then you could try to make an educate guess and then do a sensitivity analysis (i.e., vary your guess a bit and check how this affects your results/conclusions).

Best,
Wolfgang

-----Original Message-----
From: R-sig-meta-analysis [mailto:r-sig-meta-analysis-bounces using r-project.org] On Behalf Of Martin Lobo
Sent: Friday, 19 July, 2019 3:17
To: r-sig-meta-analysis using r-project.org; r-sig-meta-analysis-bounces using r-project.org; Martin Lobo
Subject: [R-meta] how do i get the ri for a meta analysis pre post test

Effect Size Measures for Pretest Posttest Control Group Designs

datT <- escalc(measure="SMCR", m1i=m_post, m2i=m_pre, sd1i=sd_pre, ni=ni, ri=ri, data=datT)
datC <- escalc(measure="SMCR", m1i=m_post, m2i=m_pre, sd1i=sd_pre, ni=ni, ri=ri, data=datC)

Hello, I need to do this type of analysis, I have all the data but I do not know how to calculate the ri. Is there any way to do it without this?

thank's

Lorenzo Mart�n Lobo MTSAC, FACC, FESC
Especialista Jerarquizado en Cardiolog�a
Jefe de Cardiolog�a Hospital Militar Campo de Mayo
Ex Jefe de Unidad Coronaria Hospital Militar Campo de Mayo
Miembro Titular de la Sociedad Argentina de Cardiolog�a
Fellow American College of Cardiology
Fellow European Society of Cardiology
Miembro del Area de Investigaci�n de la SAC
Ex Director del Consejo de Aterosclerosis y Trombosis de la SAC
Miembro Asesor del Consejo de Aterosclerosis y Trombosis de la SAC
Ex Director del Consejo de Epidemiolog�a y Prevenci�n Cardiovascular de la SAC

Miembro Asesor del Consejo de Epidemiolog�a y Prevenci�n Cardiovascular de la SAC

Instructor de ACLS de la American Heart Association