[R-meta] Meta - Bug with REML or small N?

[Jorge Teixeira]

Hi.

Let me know if you need me to provide the data for this example.
Screenshots in the bottom.

I ran this MA with REML, and the weight for random and common effects are
exactly the same! Never saw anything like this.  t2 values also don’t look
plausible.

*#1*
vo2 <- metacont(en  , em, esd, cn, cm, csd, study, method.tau = "REML",
prediction = TRUE, data = dat_vo2, sm = "MD")
vo2

Is this a bug or a particular issue of low number of studies and low sample
size?

*#2*
vo2 <- metacont(en  , em, esd, cn, cm, csd, study, method.tau = "DL",
prediction = TRUE, data = dat_vo2, sm = "MD")
vo2

I ran this with DL estimator and weights and t2 are plausible. I also ran
other similar MA using REML and this was all okay.

#1 using SMD instead of MD also looks fine.


Thanks,
Jorge


*REML:*

[image: image.png]


*DL:*
[image: image.png]

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