The effect of HMO competition on gatekeeping, usual source of care, evaluations of physician thoroughness

Center for Outcome and Effectiveness Research, Agency for Healthcare Research and Quality, Rockville, MD, USA.
The American journal of managed care (Impact Factor: 2.26). 10/2003; 9(9):618-27.
Source: PubMed


To examine the effects of HMO enrollment and HMO competition on evaluations of physician thoroughness through their effects on gatekeeping and having a usual source of care and to determine whether the effects of HMO competition spill over to individuals not enrolled in HMOs and whether these effects differ in those enrolled vs not enrolled in HMOs.
A nationally representative sample of 27 441 adults from the household component of the Community Tracking Study-Round 1 (July, 1996, through July, 1997).
A retrospective econometric analysis of Community Tracking Study data merged with measures of HMO competition.
Gatekeeping was regressed on HMO enrollment, HMO competition, and control variables using ordered logistic regression. Usual source of care was regressed on gatekeeping, HMO enrollment, HMO competition, and control variables using logistic regression. Evaluation of physician thoroughness was regressed on gatekeeping, usual source of care, HMO enrollment, HMO competition, and control variables using multivariate regression.
HMO competition increases use of gatekeeping and gatekeeping increases having a usual source of care for all individuals. For HMO enrollees, HMO competition increases having a usual source of care, whereas for those not in HMOs, it decreases having a usual source of care. For all individuals, having a usual source of care increases evaluation of physician thoroughness. For those in HMOs, gatekeeping decreases evaluation of physician thoroughness.
For HMO enrollees, the overall effect of HMO competition is to increase evaluations of physician thoroughness. For those not in HMOs, although there are HMO competition spillover effects, they are offsetting, resulting in no overall effect of HMO competition on evaluations of physician thoroughness.

Full-text preview

Available from:
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We sought to assess whether health maintenance organizations (HMOs) operating in competitive markets, or markets with substantial HMO penetration, perform better on the standardized Health Plan Employer Data and Information Set (HEDIS) and Consumer Assessment of Health Plans Survey (CAHPS) measures. We performed a secondary analysis of nonexperimental, cross-sectional data. Data were obtained from a variety of sources, including the National Committee for Quality Assurance (NCQA), Interstudy, the Area Resource File, the U.S. Office of Personnel Management, and the U.S. Department of Labor. Multiple Indicator Multiple Cause models were used to simultaneously estimate 6 latent quality variables from 35 HEDIS and CAHPS measures and to relate these latent variables to HMO competition and HMO penetration while controlling for other health plan and market characteristics. Greater competition, as measured by the Herfindahl index, was associated with inferior health plan performance on 3 of 6 quality dimensions. Plans in markets with greater HMO penetration perform better on HEDIS- but not CAHPS-based dimensions of performance. Plans that make their data available publicly perform significantly better on both the HEDIS and CAHPS domains, performing one third to three quarters of a standard deviation better than plans that don't make their results available publicly. Plans in more competitive markets in 1999 did not achieve better quality after controlling for other important covariates, although plans in markets with a high degree of HMO penetration are performing better on the HEDIS quality dimensions. Although our study design cannot determine causality, the results suggest reason to revisit the belief that competition among HMOs will inherently improve quality.
    Full-text · Article · May 2005 · Medical Care
  • [Show abstract] [Hide abstract]
    ABSTRACT: Existing research on health plan performance examines whether variation in plans' scores is related to enrollee and health plan traits, primarily using cross-sectional research designs. This study extends that literature by incorporating data on market characteristics using a longitudinal framework. We estimate multivariate growth models that relate plan performance on standard measures to market and HMO characteristics using an unbalanced panel of data for 1998 to 2002. We find that HMO competition is not associated with better performance or greater rates of improvement in performance on the HEDIS chronic care measures. HMO penetration, on the other hand, is positively associated with HEDIS performance in several of the chronic care process-and-outcomes measures but not with a greater rate of improvement through time. Our analysis indicates that a significant percentage of the unexplained variation in quality improvement is because of permanent, unobserved plan-level characteristics that future research should strive to identify.
    No preview · Article · Jan 2007 · Medical Care Research and Review
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To determine whether health plan members who saw physicians participating in a quality-based incentive program in a preferred provider organization (PPO) setting received recommended care over time compared with patients who saw physicians who did not participate in the incentive program, as per 11 evidence-based quality indicators. Administrative claims data for PPO members of a large nonprofit health plan in Hawaii collected over a 6-year period after the program was first implemented. An observational study allowing for multiple member records within and across years. Levels of recommended care received by members who visited physicians who did or did not participate in a quality incentive program were compared, after controlling for other member characteristics and the member's total number of annual office visits. Data for all PPO enrollees eligible for at least one of the 11 quality indicators in at least 1 year were collected. We found a consistent, positive association between having seen only program-participating providers and receiving recommended care for all 6 years with odds ratios ranging from 1.06 to 1.27 (95 percent confidence interval: 1.03-1.08, 1.09-1.40). Physician reimbursement models built upon evidence-based quality of care metrics may positively affect whether or not a patient receives high quality, recommended care.
    Full-text · Article · Jan 2008 · Health Services Research
Show more