Measuring children's use of emerging technologies is prerequisite to determining the effect of such use on children's health, development and learning. The Ecological Techno-Microsystem provides a theoretical foundation upon which to select test items appropriate to the measurement of children's self-reported use of the internet across home, school and community contexts. A 15 item rating scale was developed which included five items across the three environments, for example: 1) I use the internet at home; 2) I use email at school; 3) I instant message at home; 4) At home, I use the internet to play games; 5) I visit websites when I am at somebody else's house. Ninety children (37 males and 53 females,) ranging in age from 8.3 years to 12.9 years (mean 10.7 years), rated each of the 15 items on a four-category response scale (i.e., never or hardly ever, once or twice a month, once or twice a week and every day or almost every day).
Data were entered into the computer program RUM2030. Individual item fit statistics confirmed that data from all 15 items fitted the model well. Differential Item Functioning, consistent with empirical evidence, suggested gender differences in patterns of internet use during childhood. Rasch analysis (i.e., Item Map) confirmed that children with the highest self-reported internet use scores on the 15 item rating scale affirmed the most difficult items, that is, the items to which the that fewest children responded in the affirmative. In every case, items that were the most difficult to affirm assessed community-based internet use. Correspondingly, the easiest items to affirm assessed internet use at school. Because such findings are consistent with reports of children's patterns of internet use, the validity of the 15 item rating scale of children's perceptions of their use of the internet is further established.