Private health insurance: new measures of a complex and changing industry.

Private health insurance benefit payments are an integral component of estimates of national health expenditures. Recent analyses indicate that the insurance industry has undergone significant changes since the mid-1970's. As a result of these study findings and corresponding changes to estimating techniques, private health insurance estimates have been revised upward. This has had a major impact on national health expenditure estimates. This article describes the changes that have occurred in the industry, discusses some of the implications of those changes, presents a new methodology to measure private health insurance and the resulting estimate levels, and then examines concepts that underpin these estimates.