[R-meta] Predictive interval in MA with less than 10 studies

[Philippe Tadger]

Dear R-sig-MA community

I would to share my concern and ask for additional references or 
thoughts about a predictive-interval's  "rule of thumb"  presented in 
Cochrane manual: to not trust in the PI when there are fewer than 10 
studies because such calculation relies on the assumption of normality. 
Does somebody know a way to check formally on each case when using less 
than 10 studies is not safe for PI calculation?.

I can understand this limitation when the PI is calculated through a 
method that uses the methods of moments (or exact calculations like 
Riley 2001), but when the PI comes from a model that uses ML/REML (or 
iterative methods with identifiable likelihood) or Bayesian, such 
concern cannot exist. I would like to find confirmation or refutation of 
this idea.

In advance,  your time and shared wisdom are appreciated.
-- 
Kind regards/Saludos cordiales
*Philippe Tadger*
ORCID <https://orcid.org/0000-0002-1453-4105>, Reseach Gate 
<https://www.researchgate.net/profile/Philippe-Tadger>


	[[alternative HTML version deleted]]