For years, sales of the hormone replacement therapies rose, not only because the treatments could ease menopause symptoms, but also because small studies indicated a wealth of other benefits such as reduced risk of stroke and heart attack.
A few years after its approval, nesiritide fell out of use because small studies seemed to indicate an increased risk of kidney problems and an increased death rate.
Of course, the limitations, including a small total sample size, in these studies should be taken into account because small studies may overestimate the effect sizes in critical care meta-analyses and lead to erroneous conclusions [ 4].
An asymmetry in the funnel would be expected if there was publication bias with smaller studies tending to show larger ORs, because small studies with no significant statistical results would be less likely to be reported.
This was intended to eliminate studies with little precision, but thereby also reduced the number of studies included in this meta-analysis because small studies are published relatively frequently.
CT has not been widely used for breast imaging, likely because small studies indicated that it was not as sensitive and specific compared with other modalities[ 115 118] and could entail substantially greater radiation exposure.
Although publication bias could be of concern because small studies with null results tend not to be published, there was no evidence of potential publication bias in the present meta-analysis.
The different findings might be explained by type 2 error because of small study population size.
Because this small study relied on summary measures rather than taking advantage of repeated measures, statistical power to detect differences in hemodynamic outcomes may have been low.
The difference should be treated with caution because of small study groups in combination with a statistical model, which could not correct the differences in baseline (before surgery) due to non-convergence.
