Objective: The purpose of this study was to investigate an ancient hypothesis; the moon effect might increase incidence of injuries and hence admission of patients with trauma to Emergency Rooms (ERs) on full moon days.
Methods: During thirteen months, 58000 trauma patients admitted in three hospitals that had the highest load of trauma patients in Tehran were studied. Due to lack of complete data, 3543 patients (6.1%) were excluded from the study, leaving 54457 cases for further analysis. We selected lunar calendar for our study, so dates of patients' admissions were converted to lunar months and three day- periods with 15th as middle day were defined as full moon days.
Results: In our study the number of trauma patients was not increased during the full moon days against other days of lunar month. Statistical analyses of data didn't exhibit a positive relation between full moon days and increasing of trauma patient admission to ERs. An association between assault and attempted suicide was not observed around the full moon days either. The results did not show significant reduction of GCS score of patients on full moon days and there was not any increase in severity of traumatic injury sustained during full moon days.
Conclusions: It seems necessary to conduct studies regarding the probability of moon effect through on different database, geographic areas and for appropriate periods in order to reach a conclusive result.