Reply to: Modelling the effects of the weather on admissions to UK trauma units: a cross-sectional study
With great interest we read the report by Parsons et al. regarding the effects of the weather on trauma unit admissions. We would like to bring to the authors attention our study, in which we studied the same effects in an area in the Netherlands geographically and metereologically similar to the United Kingdom over a total period of 36 years, including over 350,000 patients. Although the authors of the present study looked at a particular subset of ED admissions with relatively severe injury while we included all trauma patients, overall their findings were very similar to ours. However on one point they failed to see a pattern that is most likely present in their data, because they assumed a linear model for all weather variables. In our study we used a general model which allows for non-linear relationships explaining the patterns present in the data. Our results show that a linear model provides a reasonable estimation for all variables, except for (maximum) temperature. The graph plotting the trauma incidence against the maximum temperature shows a V-shape with the lowest trauma incidence at approximately 5 degrees Celcius. Both below and above that temperature there is a sharp increase in trauma incidence and in fact, this was the strongest effect observed in our study. We would like to suggest the authors of the present study to look at their data to see if a similar pattern exists, explaining both the rise in adult trauma patients with falling minimum temperatures found by the authors, as well as the increase in patients with higher maximum temperatures reported elsewhere in the literature and also observed in the current study.
1. Modelling the effects of the weather on admissions to UK trauma units: a cross-sectional study. Parsons N, Odumenya M, Edwards A, Lecky F, Pattison G. Emerg Med J. 2010 Nov 22. [Epub ahead of print]
2. Relation of the weather and the lunar cycle with the incidence of trauma in the Groningen region over a 36-year period. Stomp W, Fidler V, ten Duis HJ, Nijsten MW. J Trauma. 2009 Nov;67(5):1103-8.
Conflict of Interest: