To study the admissions to a busy trauma unit on a day by day basis over a one year period, and to look for any correlation with local weather variation or temporal factors (day of the week, week-ends/school holidays etc. )

Admissions data for the Trauma Unit at the Leicester Royal Infirmary was collected for the calendar year of 1998. On a day-by-day basis, admissions were split into four groups: all admissions, adult admissions, admissions for fractured neck of femur (NOF) and paediatric admissions. Weather information for the local area was obtained from the Met. Office.

Details of school holidays were obtained from the local Education Department.

A number of climatic and temporal variables were examined using Poisson regression analysis for their potential importance in explaining day-to-day variation in admission rates for the four groups.

For adult and NOF admissions, none of the weather factors appeared to explain variation in incidence. For total and paediatric admissions, a number of factors appear important, with the daily maximum temperature being the single most important using univariate analysis.

Total trauma admissions increase on hot days; this is mainly due to an increase in paediatric admissions. Interestingly, there are more adult admissions in the early part of the week than later in the week. The implication is that a hot Monday will be a very busy day. The reasons for this will be explored.