The Measurement of Expenditures for Outpatient Physician and Dental Services: Methodological Findings from the Health Insurance Study
Medical Care
http://www.ncbi.nlm.nih.gov/pubmed/?term=The%20Measurement%20of%20Expenditures%20for%20Outpatient%20Physician%20and%20Dental%20Services%3A%20Methodological%20Findings%20from%20the%20Health%20Insurance%20Study