Phyll,
A note of caution about that rule of thumb. GRADE also says that in general, we should not rate up for a large effect size if we have major concerns about other issues, including risk of bias, precision, and publication bias.
A good read that you will probably find helpful is this one: http://www.jclinepi.com/article/S0895-4356(11)00184-3/fulltext
For any other issues around GRADE the JCE series is available for free (http://www.gradeworkinggroup.org/publications/JCE_series.htm)
Pablo
Pablo Alonso Coello
Centro Cochrane Iberoamericano
Instituto de Investigación Biomédica (IIB Sant Pau)
CIBER Epidemiología y Salud Pública (CIBERESP)
C/ Sant Antoni Maria Claret 167 (Pabellón 18, planta cero)
08025 Barcelona | España
[log in to unmask] | Skype: tartanedo
T: (+34) 93 553 78 14 | F: (+34) 93 553 78 09
________________________________________
De: Evidence based health (EBH) [[log in to unmask]] en nom de phyll buchanan [[log in to unmask]]
Enviat el: dissabte, 26 / juliol / 2014 15:12
Per a: [log in to unmask]
Tema: Re: Looking for help on a SIDS paper
Many thanks Ben, this is really helpful.
Phyll
> On 26 Jul 2014, at 13:48, "Djulbegovic, Benjamin" <[log in to unmask]> wrote:
>
> Phyll,
> There is currently no consensus how large the effect size should be to overcome concerns of bias ( and random error). Paul Glasziou has suggested 10 times differences, GRADE suggests multiple studies with effects size 2-5 times as large ( going in the same directions).
> We have been trying to answer this question empirically, but so far this has been hampered by lack of funding...
> Hope this helps
> Best
> Ben
>
> Sent from my iPad
> ( please excuse typos & brevity)
>
>> On Jul 26, 2014, at 8:41 AM, "Phyll Buchanan" <[log in to unmask]> wrote:
>>
>> Any thoughts on how to decide whether the effect sizes are so large they should overcome these concerns?
|