Cherkin DC, Grothaus L, Wagner EH. The effect of office visit copayments on utilization in a health maintenance organization. Med Care. 1989 Nov;27(11):1036-45.
Cherkin DC, Grothaus L, Wagner EH. The effect of office visit copayments on utilization in a health maintenance organization. Med Care. 1989 Nov;27(11):1036-45.