It is unlikely that either finding will dampen the enthusiasm for studies of G × E involving the serotonin transporter. Panagiotou and Ioannidis recently reported that the authors of primary studies are more likely to believe that a strong association exists than methodologists (referring here to the authors of meta-analyses) [39]. Evidence alone seems not be enough to change people's minds. In a careful presentation of the statistical difficulties inherent in the detection of small effects, Gelman and Weakliem [40] discuss what transpires when a theory can explain findings in any direction. They quote Jeremy Freese who describes this sort of argument as “more ‘vampirical’ than ‘empirical’—unable to be killed by mere evidence.”
