Figure 2.

e-Health users (1999–2002). The definition of current users (calculated as a percentage) is the number of subjects who have used any e-Health service in each quarter divided by the total number of subjects in the quarter (diamonds in lower curve). The definition of cumulative users (calculated as a percentage) is the number of subjects who have ever used any e-Health service during the study divided by the total number of subjects in the quarter (squares in upper curve). ^*Introduction of a prescription drug refill service in first quarter of 2001. ^**Introduction of real-time online appointment scheduling in fourth quarter of 2001.