I’m sure you could, since it’s just estimating the other half of the distribution. But you’re really going to need that assumption, which is not necessarily safe (eg. imagine flipping a fair coin—by a magician who unconsciously wants it to come up heads. It’d fail a funnel graph but not because of publication bias. And there are many ways to hire magician flippers).
If the statistical significance of the studies are valid, then it’s quite unlikely that the lines would cross the x-axis. What Ionnidis is demonstrating is an overstatement of effect size in the initial studies.
Also, Yvain’s point that a cumulative odds ratio graph is different from a generic funnel plot.
Yes.
I’m sure you could, since it’s just estimating the other half of the distribution. But you’re really going to need that assumption, which is not necessarily safe (eg. imagine flipping a fair coin—by a magician who unconsciously wants it to come up heads. It’d fail a funnel graph but not because of publication bias. And there are many ways to hire magician flippers).
If the statistical significance of the studies are valid, then it’s quite unlikely that the lines would cross the x-axis. What Ionnidis is demonstrating is an overstatement of effect size in the initial studies.
Also, Yvain’s point that a cumulative odds ratio graph is different from a generic funnel plot.