Looking at the numbers more closely leads one to question the link to nightlights though. For example, while the overall rate of ALL increased at a rate of about 1% per year for white children, there was almost no increase in ALL rates for black children. Do white children use night lights so much more frequently than black children, and if not, then why doesn't using a nightlight have an affect on the rate of leukemia for black children?
Most young children are put to bed using a nightlight or light show of some description. These cute lights however, purchased under the assumption that they will lull the child into a gentle slumber, can be keeping the little darlings awake long into the night, especially if they are left on overnight. This mistake is perpetuated by thousands of nursery product manufacturers around the world. A quick search on the internet using the term 'child nightlight' returns over five thousand results, yet almost all of them have the ability to disturb a child's sleep.