Comparative intervention study among Danish daycare children: the effect on illness of time spent outdoors

The purpose of the study was to examine the correlation between illnesses, and in particular contagious illnesses, among daycare children and the amount of time spent outdoors, and whether through the intervention of increasing the amount of time spent outdoors it is possible to lower the incidence of illness.

The study was conducted among eight daycare centres within the same county. A total of 326 children, 17 homeroom groups, were divided into two study groups. Each of the two study groups had a two-month period in which the percentage of time spent outdoors per day was almost double that of the other study group.

The overall frequency of sick days was 4%. There was no significant effect of spending more time outdoors on the number of illness episodes, length of the episode, or cause of illness.

Our negative findings are in accordance with the theory that illness among daycare children is largely a result of contact among children and the hygiene standards of the institution, and thus these are the factors that may need to be addressed to reduce the level of illness among daycare children.