Estimating the proportion of studies missing for meta-analysis due to publication bias

A potential problem with meta-analysis concerns missing studies due to publication bias. This paper focuses on one subtype of publication bias, namely selection bias (studies with unfavorable outcomes tend to be suppressed), wherein the main interest is in determining the proportion of unpublished studies.As in the well-known trim and fill method, the key assumption is that studies with quantitative outcomes extremely unfavorable for the...