Difficulties that unexpected results face to be accepted: suicide and the moon

Increased suicide risk among younger women in winter during full moon in northern Europe. An artifact or a novel finding?

“…How many more failed replications are then needed to consider a finding as false-positive? Despite the predominating null-results in previous studies and the null-finding in the Austrian study, MR suggested “It is necessary to guard against a well-documented reluctance to embrace novel suggestions, ideas and findings that depart from convention” (Semmelweis-Reflex) [ 12 ]. We do not deny that there is an influence of the moon on some biological mechanisms in certain species [ 25 ].…”

“…The combination of apophenia (the tendency to see patterns in random data), confirmation bias (the tendency to focus on evidence that is in line with our expectations or favored explanation) and hindsight bias (the tendency to see an event as having been predictable only after it has occurred) can easily lead us to false conclusions” [ 22 ]. In the present study, we both tried to address the criticism and additional hypotheses formulated by Meyer-Rochow [ 12 ] and peer-reviewers of PH as well as the obvious need for replication to uncover a false positive finding. Thus, we hope that our study not only shed light on the putative effect of the moon on suicidal behavior, which is most likely absent, but also on the dynamics related to novel and unexpected findings in science.…”

“…To bolster their argument, PH tried to replicate the findings from MR with higher powered data from Austria but found no increased suicide rate among premenopausal women during full moon phases in the winter season. In their response to this failed replication, anonymous reviewers and Meyer-Rochow et al [ 12 ] argued that the discrepancies between the Austrian and Northern Finnish results could perhaps be explained by unaccounted moderator variables, for example, latitude, length of day/night, nightly artificial brightness, and Vitamin D deficiencies. In principle, their main argument was that the main finding reported by MR could not be replicated by PH with data from Austria, because Northern Finland was situated much further north than Austria and thus, the effect of full moon on premenopausal women during winter was only apparent in Northern Finland.…”