The correlation between full moon and admission volume for penetrating injuries at a major trauma centre in South Africa

Abstract

Background: The possible effect of full moon on admission volume of trauma centres is a well-mentioned phenomenon that has been perpetuated worldwide. We aimed to review the correlation between full moon and admission volume and to interrogate any possible relationship on admission for penetrating trauma.
Methods: A retrospective study from 2012 to 2018 at Pietermaritzburg Metropolitan Trauma Service (PMTS), South Africa.
Results: A total of 8 722 patients were admitted. Eighty-three per cent (7 242/8 722) were male and the mean age was 29 years. The total number of days during the study period was 1 953, 66 of which were ‘full moon’ (FM) days and 1 887 were ‘non-full moon’ (NFM) days. There was no significant difference between gender or age distribution. The mean number of admissions per day on FM days compared with NFM days was not significant (4.1 vs 4.5, p = 0.583). A total of 3 332 patients with penetrating trauma were admitted. This constituted 42% (113/271) of admission on FM days and 38% (3 219) on NFM days, which is not statistically significant (p = 0.229). Subgroup analysis did not demonstrate any significant difference between the number of stab wounds – 28% (77/113) vs 25% (2 124/3 219) – or gunshot wounds – 13% (16/113) vs 12% (990/3 219) – between FM and NFM days.
Conclusion: The correlation between full moon and trauma admission is unfound in our setting. The perpetuating notion that ‘it must be full moon tonight’ is likely to be an urban myth with no scientific evidence for such a claim.