[R-meta] rma.mv-When a higher level can't be modeled because of one row

[Farzad Keyhan]

Sure, so, I shouldn't worry that all rows but one suggest
"measure/study" and only because of that one exceptional row, do: "~ 1
| study/measure/outcome" or "~ 1 | study/outcome/measure"?

Fred

On Mon, Nov 8, 2021 at 9:39 AM Viechtbauer, Wolfgang (SP)
<wolfgang.viechtbauer using maastrichtuniversity.nl> wrote:
>
> No, I meant using "~ 1 | study/measure/outcome" or "~ 1 | study/outcome/measure".
>
> Best,
> Wolfgang
>
> >-----Original Message-----
> >From: Farzad Keyhan [mailto:f.keyhaniha using gmail.com]
> >Sent: Monday, 08 November, 2021 16:22
> >To: Viechtbauer, Wolfgang (SP)
> >Cc: R meta
> >Subject: Re: rma.mv-When a higher level can't be modeled because of one row
> >
> >Thanks Wolfgang.
> >
> >Yes, this is just the data structure. Focusing on the "making
> >[measure] nested within study" part of your suggestion, you mean in
> >row # 3, I recode the "measure" value of 1 to 2, or even delete row #
> >3 altogether, or "~1 | measure/study/outcome" by default will take
> >care of making "measure" nested in study?
> >
> >Thank you,
> >Fred
> >
> >On Mon, Nov 8, 2021 at 4:13 AM Viechtbauer, Wolfgang (SP)
> ><wolfgang.viechtbauer using maastrichtuniversity.nl> wrote:
> >>
> >> Dear Fred,
> >>
> >> I would consider using measure as a fixed effect or making it nested within
> >study (or within outcome). But none of this might really be appropriate for a
> >dataset this small (but I assume this was just constructed for illustrating your
> >question).
> >>
> >> Best,
> >> Wolfgang
> >>
> >> >-----Original Message-----
> >> >From: Farzad Keyhan [mailto:f.keyhaniha using gmail.com]
> >> >Sent: Friday, 05 November, 2021 2:59
> >> >To: R meta
> >> >Cc: Viechtbauer, Wolfgang (SP)
> >> >Subject: Re: rma.mv-When a higher level can't be modeled because of one row
> >> >
> >> >For clarity, by a solution, I mean how can I account for the
> >> >heterogeneity in true effects attributable to "measure", while
> >> >"measure" is neither a perfect candidate for being the nestor of
> >> >study:
> >> >
> >> >random = ~1 | measure/study/outcome
> >> >
> >> >nor a perfect candidate for being crossed with study:
> >> >
> >> >random = list(~1 | study/outcome, ~1|measure)
> >> >
> >> >Thank you,
> >> >Fred
> >> >
> >> >On Thu, Nov 4, 2021 at 2:26 PM Farzad Keyhan <f.keyhaniha using gmail.com> wrote:
> >> >>
> >> >> Dear Experts,
> >> >>
> >> >> In my toy data below, if in row # 3, "measure" was 2 (instead of 1),
> >> >> then, I could take "measure" as a level higher than study:
> >> >>
> >> >> random = ~1 | measure/study/outcome
> >> >>
> >> >> But right now, because in study 2 (rows # 3 and 4) "measure" can vary,
> >> >> "measure" can't be considered a level higher than study.
> >> >>
> >> >> On the other hand, because "measure" varies only in one study, I can't
> >> >> take "measure" as a crossed random-effect either.
> >> >>
> >> >> I was wondering what solutions the expert list members might have for
> >> >> this situation?
> >> >>
> >> >> Thanks,
> >> >> Fred
> >> >>
> >> >>    measure       row   study   outcome
> >> >>    1             1     1       1
> >> >>    1             2     1       2
> >> >> #  1             3     2       1 <--- measure on this row
> >> >>    2             4     2       1
> >> >>    1             5     3       1
> >> >>    1             6     3       2