thanks for your reply, Michael!

ad primary studies:
yup, I have a large set of studies: At the moment I consider 126 data sets
in my analysis.

ad interpretation:
thats an interesting information. But usually there should be found an
effect.

ad "bit" :-):
I am irritiated, because in the plots I have studied so far, I always found
that the observed studies are open circles and the additional "mirrored"
effects are black dots. In my case, it is the other way round.

Also, most of the mirrored circels appear in the right upper corner,
indicating, that there are studies missing in my data set, which have
smaller SDs (i.e. are more precise?) and higher effect sizes?

best,

Verena




On Mon, May 26, 2014 at 12:26 PM, Michael Dewey <info@aghmed.fsnet.co.uk>wrote:

> 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
> info@aghmed.fsnet.co.uk
> http://www.aghmed.fsnet.co.uk/home.html
>
>

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