Visual inspection of the funnel plot did not demonstrate the asymmetry typically associated with publication bias (Fig.
12) Publication bias was assessed by constructing a funnel plot.
For all series, we present HSMRs for patients discharged in the financial year 2008/2009 by summarizing the differences between regular and the nine sets of variant HSMRs in bands of < 5, 5-9, and 10 + and in terms of change in funnel plot
outlier status using 99.
To investigate publication bias, a funnel plot
was generated, using the datasets from the included clinical trials.
5], the estimate accounting for funnel plot
asymmetry was 1.
Visual inspection of funnel plot
showed publication bias less likely (Fig.
In addition, we conducted trim-and-fill analyses, which, in the presence of funnel plot
asymmetry, recalculate the meta-estimate based on hypothetical, unobserved studies that would have been necessary to create a symmetrical funnel plot
(Duval and Tweedie 2000; Higgins and Green 2008).
Lemmers was aware of the Scottish study and said a funnel plot
they performed showed "the exact same results" between older and newer studies.
The funnel plot
was asymmetric in favor of smaller trials with greater effects (Egger's P = .
To assess the degree to which publication bias may have influenced the results, a funnel plot
was computed along with the associated Begg and Mazumdar's rank correlation and Egger's linear regression tests (Borenstein, 2005).
As data for all surgeons fall within predefined limits on a funnel plot
, however, we would argue that there would be little basis for using the data presented here to select one, rather than another, surgeon in this list.
Publication bias was evaluated through funnel plots
and Egger's linear regression test, with six studies demonstrating no publication bias.