Randall P. Ellis

Risk adjustment in competitive health plan markets

In the 1990s many countries have chosen to use prospective payment arrangements for health plans (e.g., health insurers, sickness funds or HMOs) together with health plan competition, as a means of creating incentives to be cost conscious, while preserving quality, innovation and responsiveness to consumer preferences. Risk adjustment is an important mechanism for attenuating problems that threaten the effectiveness of this strategy for resource allocation in health care. Without adequate risk adjustment, competing health plans have incentives to avoid individuals with predictable losses and to select predictably profitable members. This selection and the resulting risk segmentation can have adverse effects in terms of access to care, quality of care and efficiency in the production of care.This chapter first provides a conceptual framework for thinking about risk adjustment. Second, it gives an overview of the progress developing risk adjustment models in recent years. Third, several forms of risk sharing are discussed, which can be used as a tool for reducing selection in case of imperfect risk adjustment. Fourth, an overview is given of the current practice of risk adjustment and risk sharing in 11 countries. Finally some directions for future research are discussed.

Creaming, skimping and dumping: provider competition on the intensive and extensive margins.

Reimbursement incentives influence both the intensity of services and who is treated when patients differ in severity of illness. The social optimum is compared to the private Cournot-Nash solution for three provider strategies: creaming--over-provision of services to low severity patients; skimping--under-provision of services to high severity patients; and dumping--the explicit avoidance of high severity patients. Cost-based reimbursement results in overprovision of services (creaming) to all types of patients. Prospectively paid providers cream low severity patients and skimp high severity ones. If there is dumping of high severity patients, then there will also be skimping.

Optimal payment systems for health services

Demand-side cost sharing and the supply-side reimbursement system provide two separate instruments that can be used to influence the quantity of health services consumed. For risk-averse consumers, optimal payment systems--pairs of insurance and reimbursement plans--are characterized by conflict rather than consensus between patient and provider about the quantity of treatment. A model of conflict resolution based on bargaining theory is used to represent the outcome when the payment system creates divergences between desired demand and desired supply. Using that model, we describe the optimal combination of insurance and reimbursement systems that maximize consumer welfare.

Hospital response to prospective payment: Moral hazard, selection, and practice-style effects

In response to a change in reimbursement incentives, hospitals may change the intensity of services provided to a given set of patients, change the type (or severity) of patients they see, or change their market share. Each of these three responses, which we define as a moral hazard effect, a selection effect, and a practice-style effect, can influence average resource use in a population. We develop and implement a methodology for disentangling these effects using a panel data set of Medicaid psychiatric discharges in New Hampshire. We also find evidence for the form of quality competition hypothesized by Dranove (1987).

Employee Choice of Health Insurance

A new specification of health-insurance-plan choice is developed that uses a nonparametric functional form for the loss function used to evaluate insurance premiums and uncertain out-of-pocket expenditure. The approach is implemented on data resulting from one firms implementation of a new health plan with three distinct health insurance options. Health expenditure differences greater than 500 percent are observed, indicating extremely strong biased selection. Plan choices are consistent with a convex loss function for small losses, which suggests that consumers underweight high-loss/low-probability outcomes relative to low-loss/high-probability ones. Copyright 1989 by MIT Press.

Insurance principles and the design of prospective payment systems

This paper applies insurance principles to the issues of optimal outlier payments and designation of peer groups in Medicares case-based prospective payment system for hospital care. Arrows principle that full insurance after a deductible is optimal implies that, to minimize hospital risk, outlier payments should be based on hospital average loss per case rather than, as at present, based on individual case-level losses. The principle of experience rating implies defining more homogenous peer groups for the purpose of figuring average cost. The empirical significance of these results is examined using a sample of 470,568 discharges from 469 hospitals.

Risk-Adjusted Payment and Performance Assessment for Primary Care

Background:Many wish to change incentives for primary care practices through bundled population-based payments and substantial performance feedback and bonus payments. Recognizing patient differences in costs and outcomes is crucial, but customized risk adjustment for such purposes is underdeveloped. Research Design:Using MarketScan’s claims-based data on 17.4 million commercially insured lives, we modeled bundled payment to support expected primary care activity levels (PCAL) and 9 patient outcomes for performance assessment. We evaluated models using 457,000 people assigned to 436 primary care physician panels, and among 13,000 people in a distinct multipayer medical home implementation with commercially insured, Medicare, and Medicaid patients. Methods:Each outcome is separately predicted from age, sex, and diagnoses. We define the PCAL outcome as a subset of all costs that proxies the bundled payment needed for comprehensive primary care. Other expected outcomes are used to establish targets against which actual performance can be fairly judged. We evaluate model performance using R2’s at patient and practice levels, and within policy-relevant subgroups. Results:The PCAL model explains 67% of variation in its outcome, performing well across diverse patient ages, payers, plan types, and provider specialties; it explains 72% of practice-level variation. In 9 performance measures, the outcome-specific models explain 17%–86% of variation at the practice level, often substantially outperforming a generic score like the one used for full capitation payments in Medicare: for example, with grouped R2’s of 47% versus 5% for predicting “prescriptions for antibiotics of concern.” Conclusions:Existing data can support the risk-adjusted bundled payment calculations and performance assessments needed to encourage desired transformations in primary care.

Run for cover now or later? The impact of premiums, threats and deadlines on private health insurance in Australia

Between 1997 and 2000 the Australian government introduced three policy reforms that aimed to increase private health insurance coverage and reduce public hospital demand. The first provided income-based tax incentives; the second gave an across-the-board 30% premium subsidy; and the third introduced selective age-based premium increases for those enrolling after a deadline. Together the reforms increased enrolment by 50% and reduced the average age of enrollees. The deadline appeared to induce consumers to enroll now rather than delay. We estimate a model of individual insurance decisions and examine the effects of the reforms on the age and income distribution of those with private cover. We interpret the major driver of the increased enrollment as a response to a deadline and an advertising blitz, rather than a pure price response.

Explaining Health Care Expenditure Variation: Large-sample Evidence Using Linked Survey and Health Administrative Data

Explaining individual, regional, and provider variation in health care spending is of enormous value to policymakers but is often hampered by the lack of individual level detail in universal public health systems because budgeted spending is often not attributable to specific individuals. Even rarer is self-reported survey information that helps explain this variation in large samples. In this paper, we link a cross-sectional survey of 267 188 Australians age 45 and over to a panel dataset of annual healthcare costs calculated from several years of hospital, medical and pharmaceutical records. We use this data to distinguish between cost variations due to health shocks and those that are intrinsic (fixed) to an individual over three years. We find that high fixed expenditures are positively associated with age, especially older males, poor health, obesity, smoking, cancer, stroke and heart conditions. Being foreign born, speaking a foreign language at home and low income are more strongly associated with higher time-varying expenditures, suggesting greater exposure to adverse health shocks.

Disease burden profiles: an emerging tool for managing managed care

As health plans assume financial risk for providing health care services, effectively managing the health of a population remains one of the toughest challenges. This article shows how risk assessment methods can be used to measure disease burden in the full population and to discriminate levels of future health care needs within specific disease cohorts. We also examine and compare the predictive power of claims-based models within a diabetic cohort.