At 09:34 26/05/2014, Verena Weinbir wrote:>Hey guys,
>
>I have tested the metafor trim and fill function (y:SD, x:SMD)on my data
>set and yielded the following result:
>
>1. missing studies on the right: 34
That seems a lot of missing studies unless you have a very large set
of primary studies.
>2. open circles on the rights side appear to be the number of additional
>effects
>
>3. adjusted d would be higher than observed d.
Implying that the mechanism is suppressing studies which found a
large effect. This might happen if the dominant view is that there is
no effect and so when people find one they worry about their results.
>Since normally, as I understand, those parameters are the other way round
>(black dots indicating missing studies on the left, which would reduce the
>effect size), I wonder:
>
>Is there a mistake I have done? Or, if this is an actual outcome how can I
>interpret this? That its not a publication bias that influences my data
>set, but a lack of precision (studies missing that are precise -small SD-
>and have big SMD)?
Sorry but that bit is not very clear to me.
>Many thanks in advance!
>
>Verena
>
> [[alternative HTML version deleted]]
Michael Dewey
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