Dear Gladys,
Yes, you can flip the sign. In essence, this is what would happen if a
study where Y reflects depression had reverse-scored their depression
measure (such that higher values reflect *less* depression).
Whether the association between X and 'positive' measures of mental health
is the same as the association between X and 'negative' measures of mental
health (after flipping the sign of the latter) is a different issue. With
enough studies, one could code a moderator variable to indicate whether Y
was originally a positive or negative measure and examine whether the
association between X and Y differs across these two groups.
Best,
Wolfgang
-----Original Message-----
From: R-sig-meta-analysis [mailto:
r-sig-meta-analysis-bounces at r-project.org]
On Behalf Of Gladys Barragan-Jason
Sent: Monday, 18 January, 2021 15:33
To: r-sig-meta-analysis at r-project.org
Subject: [R-meta] Meta-analysis on positive and negative outcomes: Is it
correct to take the reversed r values?
Dear all,
I have a question about taking the reversed values when combining
proxies of one factor. For instance, if you're doing a meta-analysis on
impact of X on Y where Y is mental health and you have several measures
Y such as depression (r= -0.4) , stress (r=-0.1) and emotional balance
(r=+0.5-) and positive moods (r=+0.2), is it correct to transform (take to
reversed values) for "negative health" (r=+0.4 and r=0.1) and pooled
everything together or is it better to make to different meta-analysis
on positive and one on negative effects), or maybe both?
Thanks a lot for your response.
Best,
Gladys
--
------------------------------------------
Gladys Barragan-Jason, PhD. Website
Station d'Ecologie Th?orique et Exp?rimentale (SETE)
CNRS de Moulis