Background The body clock may through stimulation of melatonin secretion influence the Glasgow Coma Scale Score. The aim of this study was to investigate whether the time of presentation of children in the emergency department influences Glasgow Coma Scale scores.

Methods Retrospective review of 6649 records of children presenting to an Emergency Department in a District General Hospital from August to December 2012 with comparison of patients with a GCS of <15 seen during daytime (0700 to 1900) and night time (1900 to 0700) with regards to diagnosis, disease severity (Paediatric Early Warning Score), Glasgow Coma Scale Score, age, gender and ethnic group.

Results Out of 4034 patients attending during daytime 25 had a GCS <15 and 34 out of 2592 during night time (p = 0.005). There was no difference in age, gender, ethnicity or disease severity between groups of patients attending during day or night time. The most common condition presenting with reduced GCS both during day and night time in children were seizures (31.6%) followed by a viral respiratory tract infection (16.6%), miscellaneous other infections (20%), trauma (13.3%) and other miscellaneous conditions (18,3%). The only group of diseases with significant difference in frequency between groups were viral respiratory tract infections, which were significantly more common in children presenting with low GCS during the night (p = .0.017).

Conclusion Presentation of children with low GCS was more common during the night. Children with reduced GCS and viral respiratory tract infections presented more frequently during the night.