Development of an algorithm to identify fall-related injuries and costs in Medicare data.

BACKGROUND: Identifying fall-related injuries and costs using healthcare claims data is cost-effective and easier to implement than using medical records or patient self-report to track falls. We developed a comprehensive four-step algorithm for identifying episodes of care for fall-related injuries and associated costs, using fee-for-service Medicare and Medicare Advantage health plan claims data for 2,011 patients from 5 medical groups between 2005 and 2009. METHODS: First, as a preparatory step, we identified care received in acute inpatient and skilled nursing facility settings, in addition to emergency department visits. Second, based on diagnosis and procedure codes, we identified all fall-related claim records. Third, with these records, we identified six types of encounters for fall-related injuries, with different levels of injury and care. In the final step, we used these encounters to identify episodes of care for fall-related injuries. RESULTS: To illustrate the algorithm, we present a representative example of a fall episode and examine descriptive statistics of injuries and costs for such episodes. Altogether, we found that the results support the use of our algorithm for identifying episodes of care for fall-related injuries. When we decomposed an episode, we found that the details present a realistic and coherent story of fall-related injuries and healthcare services. Variation of episode characteristics across medical groups supported the use of a complex algorithm approach, and descriptive statistics on the proportion, duration, and cost of episodes by healthcare services and injuries verified that our results are consistent with other studies. CONCLUSIONS: This algorithm can be used to identify and analyze various types of fall-related outcomes including episodes of care, injuries, and associated costs. Furthermore, the algorithm can be applied and adopted in other fall-related studies with relative ease.

Cost effectiveness of nonoperative management versus laparoscopic appendectomy for acute uncomplicated appendicitis.

BACKGROUND: Appendectomy remains the gold standard in the treatment of acute, uncomplicated appendicitis in the United States. Nonetheless, there is growing evidence that nonoperative management is safe and efficacious. METHODS: We constructed a decision tree to compare nonoperative management of appendicitis with laparoscopic appendectomy in otherwise healthy adults. Model variables were abstracted from a literature review, data from the Healthcare Cost and Utilization Project data, the Medicare Physician Fee schedule, and the American College of Surgeons Surgical Risk Calculator. Uncertainty surrounding parameters of the model was assessed via 1-way and probabilistic sensitivity analyses. RESULTS: Operative management cost $12,213 per patient. Nonoperative management without interval appendectomy (IA) was the dominant strategy, costing $1,865 less and producing 0.03 more quality-adjusted life-years (QALYs). Nonoperative management with IA cost $4,271 more than operative management, but yielded only 0.01 additional QALY. One-way sensitivity analysis suggested operative management would become the preferred strategy if the recurrence rate was >40.5% or the total cost of appendectomy was decreased to <$5,468. Probabilistic sensitivity analysis confirmed nonoperative management without IA was the preferred strategy in 95.6% of cases. CONCLUSION: Nonoperative management without IA is the least costly, most effective treatment for acute, uncomplicated appendicitis and warrants further evaluation in a disease thought to be definitively surgical.

Effect of a falls quality improvement program on serious fall-related injuries.

OBJECTIVES: To determine whether a program that improves the quality of care for falls reduces the number of episodes of care for serious fall-related injuries. DESIGN: Nonrandomized controlled trial. SETTING: Four community-based primary care practices. PARTICIPANTS: Individuals aged 75 and older who screened positive for fall risk. INTERVENTION: A multicomponent quality improvement program (Assessing Care of Vulnerable Elders Practice Redesign for Improved Medical Care for Elders) involving face-to-face clinician education about falls and decision support to prompt primary care providers to implement appropriate care, including referral to appropriate community resources, in response to individuals screening positive for fall risk. MEASUREMENTS: Episodes of care for selected fall-related injuries, based on healthcare claims. RESULTS: Of 1,791 individuals with data available for analysis, 1,187 were in the intervention group, and 604 were in the control group. Mean age was 83, and more than two-thirds of the sample were women. After adjusting for potential confounders, there were no statistically significant differences between intervention and control groups in episodes of care for fall-related injuries during the 12-month (incidence rate ratio (IRR) 1.27, 95% confidence interval (CI) = 0.93-1.73) or 24-month (IRR 1.18, 95% CI = 0.93-1.49) period after initiation of the intervention. CONCLUSION: Despite improving the care of falls, this quality improvement initiative did not result in a change in the number of episodes of care for serious fall-related injuries. Future work in community-based settings should test higher-intensity interventions to reduce fall-related injuries.

Cost-effectiveness of CT screening in the National Lung Screening Trial.

BACKGROUND: The National Lung Screening Trial (NLST) showed that screening with low-dose computed tomography (CT) as compared with chest radiography reduced lung-cancer mortality. We examined the cost-effectiveness of screening with low-dose CT in the NLST. METHODS: We estimated mean life-years, quality-adjusted life-years (QALYs), costs per person, and incremental cost-effectiveness ratios (ICERs) for three alternative strategies: screening with low-dose CT, screening with radiography, and no screening. Estimations of life-years were based on the number of observed deaths that occurred during the trial and the projected survival of persons who were alive at the end of the trial. Quality adjustments were derived from a subgroup of participants who were selected to complete quality-of-life surveys. Costs were based on utilization rates and Medicare reimbursements. We also performed analyses of subgroups defined according to age, sex, smoking history, and risk of lung cancer and performed sensitivity analyses based on several assumptions. RESULTS: As compared with no screening, screening with low-dose CT cost an additional $1,631 per person (95% confidence interval [CI], 1,557 to 1,709) and provided an additional 0.0316 life-years per person (95% CI, 0.0154 to 0.0478) and 0.0201 QALYs per person (95% CI, 0.0088 to 0.0314). The corresponding ICERs were $52,000 per life-year gained (95% CI, 34,000 to 106,000) and $81,000 per QALY gained (95% CI, 52,000 to 186,000). However, the ICERs varied widely in subgroup and sensitivity analyses. CONCLUSIONS: We estimated that screening for lung cancer with low-dose CT would cost $81,000 per QALY gained, but we also determined that modest changes in our assumptions would greatly alter this figure. The determination of whether screening outside the trial will be cost-effective will depend on how screening is implemented. (Funded by the National Cancer Institute; NLST ClinicalTrials.gov number, NCT00047385.).

The value of health information technology: filling the knowledge gap.

Despite rapid growth in the rate of adoption of health information technology (HIT), and in the volume of evaluation studies, the existing knowledge base for the value of HIT is not advancing at a similar rate. Most evaluation articles are limited in that they use incomplete measures of value and fail to report the important contextual and implementation characteristics that would allow for an adequate understanding of how the study results were achieved. To address these deficiencies, we present a conceptual framework for measuring HIT value and we propose a checklist of characteristics that should be considered in HIT evaluation studies. The framework consists of 3 key principles: 1) value includes both costs and benefits; 2) value accrues over time; and 3) value depends on which stakeholder's perspective is used. Through examples, we show how these principles can be used to guide and improve HIT evaluation studies. The checklist includes a list of contextual and implementation characteristics that are important for interpretation of results. These improvements will make future studies more useful for policy makers and more relevant to the current needs of the healthcare system.

Redirecting Innovation in U.S. Health Care: Options to Decrease Spending and Increase Value.

New medical technologies are a leading driver of U.S. health care spending. This article identifies promising policy options to change which medical technologies are created, with two related policy goals: (1) Reduce total health care spending with the smallest possible loss of health benefits, and (2) ensure that new medical products that increase spending are accompanied by health benefits that are worth the spending increases. The analysis synthesized information from peer-reviewed and other literature, a panel of technical advisors convened for the project, and 50 one-on-one expert interviews. The authors also conducted case studies of eight medical products. The following features of the U.S. health care environment tend to increase spending without also conferring major health benefits: lack of basic scientific knowledge about some disease processes, costs and risks of U.S. Food and Drug Administration (FDA) approval, limited rewards for medical products that could lower spending, treatment creep, and the medical arms race. The authors identified ten policy options that would help advance the two policy goals. Five would do so by reducing the costs and/or risks of invention and obtaining FDA approval: (1) Enable more creativity in funding basic science, (2) offer prizes for inventions, (3) buy out patents, (4) establish a public-interest investment fund, and (5) expedite FDA reviews and approvals. The other five options would do so by increasing market rewards for products: (1) Reform Medicare payment policies, (2) reform Medicare coverage policies, (3) coordinate FDA approval and Centers for Medicare & Medicaid Services coverage processes, (4) increase demand for technologies that decrease spending, and (5) produce more and more-timely technology assessments.

A cost-effectiveness analysis of a proposed national falls prevention program.

Falls are a major health concern for elderly people and cause substantial health care costs. The authors used meta-analytic findings on the effectiveness of fall prevention interventions to determine cost-effectiveness of a proposed Medicare fall prevention program for people who experience a recent fall. Using published clinical trial data, the authors constructed a population-based economic model and estimated that, in the base case, the program could prevent a half million people from falling again within a year. From the model, under most circumstances the cost-effectiveness ratio is less than $1500 per person prevented from experiencing a recurrent fall. Paying for a fall prevention program to increase the use of evidence-based interventions would be a cost-effective use of Medicare dollars.

Health information technology and physicians' knowledge of drug costs.

OBJECTIVE: To examine whether physicians' use of information technology (IT) was associated with better knowledge of drug costs. STUDY DESIGN/METHODS: A 2007 statewide survey of 247 primary care physicians in Hawaii regarding IT use and self-reported knowledge of formularies, copayments, and retail prices. RESULTS: Approximately 8 in 10 physicians regularly used IT in clinical care: 60% Internet, 54% e-prescribing, 43% electronic health records (EHRs), and 37% personal digital assistants (PDAs). However, fewer than 1 in 5 often knew drug costs when prescribing, and more than 90% said lack of knowledge of formularies and copayments remained a barrier to considering drug costs for patients. In multivariate analyses adjusting for sex, practice size, years in practice, number of formularies, and use of clinical resources (eg, pharmacists), use of the Internet -- but not e-prescribing, EHRs, or PDAs -- was associated with physicians reporting slightly better knowledge of copayments (adjusted predicted percentage of 23% vs 11%; P = .04). No type of IT was associated with better knowledge of formularies or retail prices. CONCLUSIONS: Despite high rates of IT use, there was only a modest association between physicians' use of IT and better knowledge of drug costs. Future investments in health IT should consider how IT design can be improved to make it easier for physicians to access cost information at the point of care.

Medicare HMO impact on utilization at the end of life.

OBJECTIVE: To estimate the effect of independent practice association (IPA) model HMOs and the Kaiser Foundation Health Plan's group model on inpatient utilization of Medicare beneficiaries in the last 2 years of life, compared with traditional fee-for-service (FFS) coverage. STUDY DESIGN: Data from the Centers for Medicare & Medicaid Services were linked to inpatient discharge data from the California Office of Statewide Health Planning and Development for 1991-2001. A sample of aged Medicare beneficiaries who died between January 1998 and June 2001 and were continuously enrolled during the 2 years before death in (1) FFS (n = 234,498), (2) an IPA (n = 109,577), or (3) Kaiser (n = 29,434) were selected. METHODS: The probability of at least 1 hospitalization, number of inpatient days given at least 1 hospitalization, and total inpatient days per year in the last 2 years of life were estimated for each subgroup. A 2-part regression model, which adjusted for age, sex, Medicaid status, race, ethnicity, and chronic condition associated with the last hospitalization, was applied to determine the HMO-FFS difference in inpatient utilization during the last 2 years of life. RESULTS: During their last 2 years of life, decedents in IPAs and Kaiser used approximately 34% and 51% fewer inpatient days, respectively, than decedents in FFS. CONCLUSIONS: Medicare beneficiaries who died while enrolled in an HMO, particularly Kaiser, had many fewer hospital days during the 2 years before death than beneficiaries who died with FFS coverage.

Attrition in the RAND Health Insurance Experiment: a response to Nyman.

In a prior article in this journal, John Nyman argues that the effect on health care use and spending found in the RAND Health Insurance Experiment is an artifact of greater voluntary attrition in the cost-sharing plans relative to the free care plan. Specifically, he speculates that those in the cost-sharing plans, when faced with a hospitalization, withdrew. His argument is implausible because (1) families facing a hospitalization would be worse off financially by withdrawing; (2) a large number of observational studies find a similar effect of cost sharing on use; (3) those who left did not differ in their utilization prior to leaving; (4) if there had been no attrition and cost sharing did not reduce hospitalization rates, each adult in each family that withdrew would have had to have been hospitalized once each year for the duration of time they would otherwise have been in the experiment, an implausibly high rate; (5) there are benign explanations for the higher attrition in the cost-sharing plans. Finally, we obtained follow-up health-status data on the great majority of those who left prematurely. We found the health-status findings were insensitive to the inclusion of the attrition cases.

Waste in the U.S. Health care system: a conceptual framework.

CONTEXT: Health care costs in the United States are much higher than those in industrial countries with similar or better health system performance. Wasteful spending has many undesirable consequences that could be alleviated through waste reduction. This article proposes a conceptual framework to guide researchers and policymakers in evaluating waste, implementing waste-reduction strategies, and reducing the burden of unnecessary health care spending. METHODS: This article divides health care waste into administrative, operational, and clinical waste and provides an overview of each. It explains how researchers have used both high-level and sector- or procedure-specific comparisons to quantify such waste, and it discusses examples and challenges in both waste measurement and waste reduction. FINDINGS: Waste is caused by factors such as health insurance and medical uncertainties that encourage the production of inefficient and low-value services. Various efforts to reduce such waste have encountered challenges, such as the high costs of initial investment, unintended administrative complexities, and trade-offs among patients', payers', and providers' interests. While categorizing waste may help identify and measure general types and sources of waste, successful reduction strategies must integrate the administrative, operational, and clinical components of care, and proceed by identifying goals, changing systemic incentives, and making specific process improvements. CONCLUSIONS: Classifying, identifying, and measuring waste elucidate its causes, clarify systemic goals, and specify potential health care reforms that-by improving the market for health insurance and health care-will generate incentives for better efficiency and thus ultimately decrease waste in the U.S. health care system.

Predicting outcomes of primary care patients with major depression: development of a depression prognosis index.

OBJECTIVE: Depression research and practice focus increasingly on diverse patient populations with varying probabilities of response to clinical care. Prognostic indices use preexisting patient characteristics to estimate the probability of subsequent negative clinical outcomes and are useful tools for improving the study and care of diverse populations. Few such measures, however, have been developed for mental health conditions. This study developed and validated a depression prognosis measure for primary care patients with major depression. METHODS: Consecutive patients in 108 primary care practices were screened for depression, and 1,471 with major depression were enrolled. A Depression Prognosis Index (DPI) predicting persistent depression six months after baseline was developed for a random one-third subsample and validated with the remaining two-thirds. Models included prior treatment, demographic characteristics, comorbidities, and other physical, psychological, and social predictors. RESULTS: Sixty-four percent to 65% of patients classified by baseline DPI score as being in the sample quartile with the worst prognosis had probable major depression six months later, compared with 14% to 15% in the best-prognosis quartile. The DPI had an R2 of .40 in the development sample and .27 in the validation sample. Important predictors included severity of depression symptoms at baseline, social support, common physical symptoms, and having completed three months of antidepressants at sample entry. CONCLUSIONS: The ability of the DPI to predict six-month outcomes compares favorably to that of prognostic indices for general medical problems. These results validate the DPI and provide conceptual guidance for further development of depression risk stratification instruments for clinical and research use.

Can a chronic care model collaborative reduce heart disease risk in patients with diabetes?

BACKGROUND: There is a need to identify effective practical interventions to decrease cardiovascular disease risk in patients with diabetes. OBJECTIVE: We examine the impact of participation in a collaborative implementing the chronic care model (CCM) on the reduction of cardiovascular disease risk in patients with diabetes. DESIGN: Controlled pre- and postintervention study. PATIENTS/PARTICIPANTS: Persons with diabetes receiving care at 13 health care organizations exposed to the CCM collaborative and controls receiving care in nonexposed sites. MEASUREMENTS AND MAIN RESULTS: Ten-year risk of cardiovascular disease; determined using a modified United Kingdom Prospective Diabetes Study risk engine score. A total number of 613 patients from CCM intervention sites and 557 patients from usual care control sites met the inclusion criteria. The baseline mean 10-year risk of cardiovascular disease was 31% for both the intervention group and the control group. Participants in both groups had improved blood pressure, lipid levels, and HbA1c levels during the observation period. Random intercept hierarchical regression models showed that the intervention group had a 2.1% (95% CI -3.7%, -0.5%) greater reduction in predicted risk for future cardiovascular events when compared to the control group. This would result in a reduced risk of one cardiovascular disease event for every 48 patients exposed to the intervention. CONCLUSIONS: Over a 1-year interval, this collaborative intervention using the CCM lowered the cardiovascular disease risk factors of patients with diabetes who were cared for in the participating organization's settings. Further work could enhance the impact of this promising multifactorial intervention on cardiovascular disease risk reduction.

Perceived causes of disability added prognostic value beyond medical conditions and functional status.

OBJECTIVE: This study's objective was to determine the incremental benefit of respondent subjective attribution of functional decline beyond relying solely on disease burden in predicting survival. STUDY DESIGN AND SETTINGS: A total of 9447 older adults from the Second Longitudinal Study on Aging, a probability sample of community dwelling adults aged 70 or older, were evaluated. Survival was based on status at follow-up interview 3-4 years after baseline interview. Logistic regression was performed using demographic variables and coexisting diseases as a baseline, then adding functional status measures (ADL, IADL) and individual subjective attribution of functional limitation in subsequent models. RESULTS: The predictions improved significantly with the addition of functional status measures (P<0.001) and the individual subjective attribution of functional limitation (P<0.001). For example, the probability of mortality for individuals with cancer was 17.3%, but 28.8% of those with cancer and functional limitations died as did 50% of those with cancer who reported functional limitations attributable to cancer. CONCLUSION: Among persons who can make a specific attribution of their functional limitation, the attribution may have value as a marker of severity of disease and serve as a good predictive measure for mortality, especially in specific illnesses such as cancer.

Is cataract surgery cost-effective among older patients with a low predicted probability for improvement in reported visual functioning?

INTRODUCTION: Although cataract surgery has been demonstrated to be effective and cost-effective, 5% to 20% of patients do not benefit functionally from the procedure. This study examines the cost-effectiveness of cataract surgery versus watchful waiting in a subgroup of patients who had less than a 30% predicted probability of reporting improvements in visual function after surgery. METHODS: Randomized trial (first eye surgery vs. watchful waiting) of 250 patients who based on a cataract surgery index (CSI) were felt to have less than a 30% probability of reporting improvements in visual functioning after surgery. Cost was estimated using monthly resource utilization surveys and Medicare billing and payment data. Effectiveness was evaluated at 6 months using the Activities of Daily Vision Scale (ADVS) and the Health Utilities Index, Mark 3 (HUI3). RESULTS: In terms of overall utility, the incremental cost-effectiveness of surgery was Dollars 38,288/QALY. In the subgroup of patients with a CSI score > 11 (< 20% probability of improvement), the cost-effectiveness of cataract surgery was Dollars 53,500/QALY. Sensitivity analysis demonstrated that often this population of patients may not derive a utility benefit with surgery. CONCLUSION: Cataract surgery is cost-effective even in a subpopulation of patient with a lower, < 30%, predicted probability of reporting improved visual functioning after surgery. There may be a subgroup of patients, CSI > 11, for whom a strategy of watchful waiting may be equally effective and considerably less expensive.

Costs and benefits of health information technology.

OBJECTIVES: An evidence report was prepared to assess the evidence base regarding benefits and costs of health information technology (HIT) systems, that is, the value of discrete HIT functions and systems in various healthcare settings, particularly those providing pediatric care. DATA SOURCES: PubMed, the Cochrane Controlled Clinical Trials Register, and the Cochrane Database of Reviews of Effectiveness (DARE) were electronically searched for articles published since 1995. Several reports prepared by private industry were also reviewed. REVIEW METHODS: Of 855 studies screened, 256 were included in the final analyses. These included systematic reviews, meta-analyses, studies that tested a hypothesis, and predictive analyses. Each article was reviewed independently by two reviewers; disagreement was resolved by consensus. RESULTS: Of the 256 studies, 156 concerned decision support, 84 assessed the electronic medical record, and 30 were about computerized physician order entry (categories are not mutually exclusive). One hundred twenty four of the studies assessed the effect of the HIT system in the outpatient or ambulatory setting; 82 assessed its use in the hospital or inpatient setting. Ninety-seven studies used a randomized design. There were 11 other controlled clinical trials, 33 studies using a pre-post design, and 20 studies using a time series. Another 17 were case studies with a concurrent control. Of the 211 hypothesis-testing studies, 82 contained at least some cost data. We identified no study or collection of studies, outside of those from a handful of HIT leaders, that would allow a reader to make a determination about the generalizable knowledge of the study's reported benefit. Beside these studies from HIT leaders, no other research assessed HIT systems that had comprehensive functionality and included data on costs, relevant information on organizational context and process change, and data on implementation. A small body of literature supports a role for HIT in improving the quality of pediatric care. Insufficient data were available on the costs or cost-effectiveness of implementing such systems. The ability of Electronic Health Records (EHRs) to improve the quality of care in ambulatory care settings was demonstrated in a small series of studies conducted at four sites (three U.S. medical centers and one in the Netherlands). The studies demonstrated improvements in provider performance when clinical information management and decision support tools were made available within an EHR system, particularly when the EHRs had the capacity to store data with high fidelity, to make those data readily accessible, and to help translate them into context-specific information that can empower providers in their work. Despite the heterogeneity in the analytic methods used, all cost-benefit analyses predicted substantial savings from EHR (and health care information exchange and interoperability) implementation: The quantifiable benefits are projected to outweigh the investment costs. However, the predicted time needed to break even varied from three to as many as 13 years. CONCLUSIONS: HIT has the potential to enable a dramatic transformation in the delivery of health care, making it safer, more effective, and more efficient. Some organizations have already realized major gains through the implementation of multifunctional, interoperable HIT systems built around an EHR. However, widespread implementation of HIT has been limited by a lack of generalizable knowledge about what types of HIT and implementation methods will improve care and manage costs for specific health organizations. The reporting of HIT development and implementation requires fuller descriptions of both the intervention and the organizational/economic environment in which it is implemented.

Is adjuvant therapy for older patients with node (+) early breast cancer cost-effective?

BACKGROUND: Node (+) breast cancer represents over 40% of cases in older women and currently there is a debate whether adjuvant therapy for all older women is cost-effective. PURPOSE: To evaluate if adjuvant treatment for early-stage (Stage I-IIIa) node (+) breast cancer with hormone therapy, chemotherapy, or combination therapy is cost-effective in older patients. DESIGN: A decision-analysis model for 65, 75, and 85 year-old female breast cancer patients using life tables integrated the cost of treatment in dollars and impact in length and quality of life. Both estrogen receptor (ER) (-) and (+) patients were considered. The primary data sources were meta-analysis from the Early Breast Cancer Trialists' Collaborative Group and the Red Book Average Wholesale Price for drugs. The cost of treatment in dollars and impact of quality of life was examined. Scenarios were used when treatment benefit was uncertain. The incremental cost-effectiveness of different treatment strategies were then compared and mapped graphically. RESULTS: Adjuvant therapy is cost-effective in 65 year-old women with early breast cancer. In a 75 year-old ER (+) patient, hormone therapy is cost-effective, $10,965/quality-adjusted life years (QALY), but chemotherapy was more cost-effective, $27,406/QALY, if one assumed it was as efficacious as in a 65 year-old woman. In a 75 year-old ER (-) patient, chemotherapy was cost-effective at $42,605 with the same assumption. In an 85 year-old ER (+) patient, hormone therapy was cost-effective, $26,463/QALY, if efficacy is not age-sensitive, but chemotherapy was not as cost-effective for either ER (+) or ER (-) patients. CONCLUSION: Treatment decisions for older breast cancer patients suffer from the lack of sufficient clinical trial data. Decision-analytic models can help policy makers who are faced with decisions about whether to support adjuvant therapy in older breast cancer patients and also outline the important parameters that need to be considered in such a decision.

The lifetime burden of chronic disease among the elderly.

The high costs of treating chronic diseases suggest that reducing their prevalence would improve Medicare's financial stability. In this paper we examine the impact of selected chronic diseases on the distribution of health spending and its variation over the course of disease. We also use a microsimulation model to estimate these conditions' impact on life expectancy and health spending from age sixty-five to death. A sixty-five-year-old with a serious chronic illness spends 1000-2000 dollars more per year on health care than a similar adult without the condition. However, cumulative Medicare payments are only modestly higher for the chronically ill because of their shorter life expectancy.

A meta-analysis of interventions to improve care for chronic illnesses.

OBJECTIVE: To use empirical data from previously published literature to address 2 research questions: (1) Do interventions that incorporate at least 1 element of the Chronic Care Model (CCM) result in improved outcomes for specific chronic illnesses? (2) Are any elements essential for improved outcomes? STUDY DESIGN: Meta-analysis. METHODS: Articles were identified from narrative literature reviews and quantitative meta-analyses, each of which covered multiple bibliographic databases from inception to March 2003. We supplemented this strategy by searching the MEDLINE database (1998-2003) and by consulting experts. We included randomized and nonrandomized controlled trials of interventions that contained 1 or more elements of the CCM for asthma, congestive heart failure (CHF), depression, and diabetes. We extracted data on clinical outcomes, quality of life, and processes of care. We then used random-effects modeling to compute pooled standardized effect sizes and risk ratios. RESULTS: Of 1345 abstracts screened, 112 studies contributed data to the meta-analysis: asthma, 27 studies; CHF, 21 studies; depression, 33 studies; and diabetes, 31 studies. Interventions with at least 1 CCM element had consistently beneficial effects on clinical outcomes and processes of care across all conditions studied. The effects on quality of life were mixed, with only the CHF and depression studies showing benefit. Publication bias was noted for the CHF studies and a subset of the asthma studies. CONCLUSIONS: Interventions that contain at least 1 CCM element improve clinical outcomes and processes of care--and to a lesser extent, quality of life--for patients with chronic illnesses.