Cost-effectiveness of using a gene expression profiling test to aid in identifying the primary tumour in patients with cancer of unknown primary.

We aimed to investigate the cost-effectiveness of a 2000-gene-expression profiling (GEP) test to help identify the primary tumor site when clinicopathological diagnostic evaluation was inconclusive in patients with cancer of unknown primary (CUP). We built a decision-analytic-model to project the lifetime clinical and economic consequences of different clinical management strategies for CUP. The model was parameterized using follow-up data from the Manitoba Cancer Registry, cost data from Manitoba Health administrative databases and secondary sources. The 2000-GEP-based strategy compared to current clinical practice resulted in an incremental cost-effectiveness ratio (ICER) of $44,151 per quality-adjusted life years (QALY) gained. The total annual-budget impact was $36.2 million per year. A value-of-information analysis revealed that the expected value of perfect information about the test's clinical impact was $4.2 million per year. The 2000-GEP test should be considered for adoption in CUP. Field evaluations of the test are associated with a large societal benefit.

Cost analysis of breast cancer diagnostic assessment programs.

OBJECTIVES: Diagnostic assessment programs (daps) appear to improve the diagnosis of cancer, but evidence of their cost-effectiveness is lacking. Given that no earlier study used secondary financial data to estimate the cost of diagnostic tests in the province of Ontario, we explored how to use secondary financial data to retrieve the cost of key diagnostic test services in daps, and we tested the reliability of that cost-retrieving method with hospital-reported costs in preparation for future cost-effectiveness studies. METHODS: We powered our sample at an alpha of 0.05, a power of 80%, and a margin of error of ±5%, and randomly selected a sample of eligible patients referred to a dap for suspected breast cancer during 1 January-31 December 2012. Confirmatory diagnostic tests received by each patient were identified in medical records. Canadian Classification of Health Intervention procedure codes were used to search the secondary financial data Web portal at the Ontario Case Costing Initiative for an estimate of the direct, indirect, and total costs of each test. The hospital-reported cost of each test received was obtained from the host-hospital's finance department. Descriptive statistics were used to calculate the cost of individual or group confirmatory diagnostic tests, and the Wilcoxon signed-rank test or the paired t-test was used to compare the Ontario Case Costing Initiative and hospital-reported costs. RESULTS: For the 191 identified patients with suspected breast cancer, the estimated total cost of $72,195.50 was not significantly different from the hospital-reported total cost of $72,035.52 (p = 0.24). Costs differed significantly when multiple tests to confirm the diagnosis were completed during one patient visit and when confirmatory tests reported in hospital data and in medical records were discrepant. The additional estimated cost for non-salaried physicians delivering diagnostic services was $28,387.50. CONCLUSIONS: It was feasible to use secondary financial data to retrieve the cost of key diagnostic tests in a breast cancer dap and to compare the reliability of the costs obtained by that estimation method with hospital-reported costs. We identified the strengths and challenges of each approach. Lessons learned from this study have to be taken into consideration in future cost-effectiveness studies.

The clinical significance of occult gynecologic primary tumours in metastatic cancer.

OBJECTIVE: We estimated the frequency of occult gynecologic primary tumours (gpts) in patients with metastatic cancer from an uncertain primary and evaluated the effect on disease management and overall survival (os). METHODS: We used Manitoba administrative health databases to identify all patients initially diagnosed with metastatic cancer during 2002-2011. We defined patients as having an "occult" primary tumour if the primary was classified at least 6 months after the initial diagnosis. Otherwise, we considered patients to have "obvious" primaries. We then compared clinicopathologic and treatment characteristics and 2-year os for women with occult and with obvious gpts. We used Cox regression adjustment and propensity score methods to assess the effect on os of having an occult gpt. RESULTS: Among the 5953 patients diagnosed with metastatic cancer, occult primary tumours were more common in women (n = 285 of 2552, 11.2%) than in men (n = 244 of 3401, 7.2%). In women, gpts were the most frequent occult primary tumours (n = 55 of 285, 19.3%). Compared with their counterparts having obvious gpts, women with occult gpts (n = 55) presented with similar histologic and metastatic patterns but received fewer gynecologic diagnostic examinations during diagnostic work-up. Women with occult gpts were less likely to undergo surgery, waited longer for radiotherapy, and received a lesser variety of chemotherapeutic agents. Having an occult compared with an obvious gpt was associated with decreased os (hazard ratio: 1.62; 95% confidence interval: 1.2 to 2.35). Similar results were observed in adjusted analyses. CONCLUSIONS: In women with metastatic cancer from an uncertain primary, gpts constitute the largest clinical entity. Accurate diagnosis of occult gpts early in the course of metastatic cancer might lead to more effective treatment decisions and improved survival outcomes.

Cost-effectiveness of a fracture liaison service--a real-world evaluation after 6 years of service provision.

UNLABELLED: The cost-effectiveness of a less intensive fracture liaison service is unknown. We evaluated a fracture liaison service that had been educating and referring patients for secondary prevention of osteoporotic fractures for 6 years. Our results suggest that a less intensive fracture liaison service, with moderate effectiveness, can still be worthwhile. INTRODUCTION: Fragility fractures are common among older patients; the risk of re-fracture is high but could be reduced with treatments; different versions of fracture liaison service have emerged to reduce recurrent osteoporotic fractures. But the cost-effectiveness of a less intensive model is unknown. The objective of this study was to assess the cost-effectiveness of the Ontario Fracture Clinic Screening program, a fracture liaison service that had been educating and referring fragility fracture patients across Ontario, Canada to receive bone mineral density testing and osteoporosis treatments since 2007. METHODS: We developed a Markov model to assess the cost-effectiveness of the program over the patients' remaining lifetime, using rates of bone mineral density testing and osteoporosis treatment and cost of intervention from the program, and supplemented it with the published literature. The analysis took the perspective of a third-party health-care payer. Costs and benefits were discounted at 5 % per year. Sensitivity analyses assessed the effects of different assumptions on the results. RESULTS: The program improved quality-adjusted life-years (QALYs) by 4.3 years and led to increased costs of CAD $83,000 for every 1000 patients screened, at a cost of $19,132 per QALY gained. The enhanced model, the Bone Mineral Density (BMD) Fast Track program that includes ordering bone mineral density testing, was even more cost-effective ($5720 per QALY gained). CONCLUSIONS: The Ontario Fracture Clinic Screening program appears to be a cost-effective way to reduce recurrent osteoporotic fractures.

Estimating the costs of intensity-modulated and 3-dimensional conformal radiotherapy in Ontario.

BACKGROUND: Radiotherapy is a common treatment for many cancers, but up-to-date estimates of the costs of radiotherapy are lacking. In the present study, we estimated the unit costs of intensity-modulated radiotherapy (imrt) and 3-dimensional conformal radiotherapy (3D-crt) in Ontario. METHODS: An activity-based costing model was developed to estimate the costs of imrt and 3D-crt in prostate cancer. It included the costs of equipment, staff, and supporting infrastructure. The framework was subsequently adapted to estimate the costs of radiotherapy in breast cancer and head-and-neck cancer. We also tested various scenarios by varying the program maturity and the use of volumetric modulated arc therapy (vmat) alongside imrt. RESULTS: From the perspective of the health care system, treating prostate cancer with imrt and 3D-crt respectively cost $12,834 and $12,453 per patient. The cost of radiotherapy ranged from $5,270 to $14,155 and was sensitive to analytic perspective, radiation technique, and disease site. Cases of head-and-neck cancer were the most costly, being driven by treatment complexity and fractions per treatment. Although imrt was more costly than 3D-crt, its cost will likely decline over time as programs mature and vmat is incorporated. CONCLUSIONS: Our costing model can be modified to estimate the costs of 3D-crt and imrt for various disease sites and settings. The results demonstrate the important role of capital costs in studies of radiotherapy cost from a health system perspective, which our model can accommodate. In addition, our study established the need for future analyses of imrt cost to consider how vmat affects time consumption.

Population-based trends in systemic therapy use and cost for cancer patients in the last year of life.

BACKGROUND: The use of systemic therapy near the end of life can expose cancer patients to severe toxicity for minimal survival gain and comes with a high cost. Early palliative care is recommended, but there is evidence that aggressive care remains common. To better understand those patterns, the present study set out to describe trends in systemic therapy use and cost for cancer patients in the last year of life. METHODS: Using the BC Cancer Registry, a retrospective population-based cohort of cancer decedents (2002-2007) was identified and linked to systemic therapy records. The outcomes of interest were any systemic therapy use and total systemic therapy costs during the last year of life. Multiple logistic regression (systemic therapy use) and generalized linear regression (costs) were conducted, adjusting for age, sex, and survival. Subgroup analyses were performed for patients with primary colorectal, lung, prostate, or breast cancer. RESULTS: From 2002 to 2007, use of systemic therapy in the last 12-4 months of life increased by 21% (95% ci: 10% to 33%); no significant change in use in the last 3 months of life was observed. Costs for both periods increased over time, by 48% (95% ci: 36% to 63%) and by 33% (95% ci: 19% to 49%) respectively. The trends varied across cancer sites, with the greatest increases being observed for lung and colorectal cancer patients. CONCLUSIONS: The use and costs of systemic therapy have generally been increasing, putting pressure on health care providers and payers, but the quality-of-life implications for patients must be better understood.

Temporal association between home nursing and hospital costs at end of life in three provinces.

BACKGROUND: Research has demonstrated that increases in palliative homecare nursing are associated with a reduction in the rate of subsequent hospitalizations. However, little evidence is available about the cost-savings potential of palliative nursing when accounting for both increased nursing costs and potentially reduced hospital costs. METHODS: Our retrospective cohort study included cancer decedents from British Columbia, Ontario, and Nova Scotia who received any palliative nursing in the last 6 months of life. A Poisson regression analysis was used to determine the association of increased nursing costs (in 2-week blocks) on the relative average hospital costs in the subsequent 2-week block and on the overall total cost (hospital costs plus nursing costs in the preceding 2-week block). RESULTS: The cohort included 58,022 cancer decedents. Results of the analysis for the last month of life showed an association between increased nursing costs and decreased relative hospital costs in comparisons with a reference group (>0 to 1 hour nursing in the block): the maximum decrease was 55% for Ontario, 31% for British Columbia, and 38% for Nova Scotia. Also, increased nursing costs in the last month were almost always associated with lower total costs in comparison with the reference. For example, cost savings per person-block ranged from $376 (>10 nursing hours) to $1,124 (>4 to 6 nursing hours) in British Columbia. CONCLUSIONS: In the last month of life, increased palliative nursing costs (compared with costs for >0 to 1 hour of nursing in the block) were associated with lower relative hospital costs and a lower total cost in a subsequent block. Our research suggests a cost-savings potential associated with increased community-based palliative nursing.

Economic evaluation of hormonal therapies for postmenopausal women with estrogen receptor-positive early breast cancer in Canada.

BACKGROUND: Aromatase inhibitor (ai) therapy has been subjected to numerous cost-effectiveness analyses. However, with most ais having reached the end of patent protection and with maturation of the clinical trials data, a re-analysis of ai cost-effectiveness and a consideration of ai use as part of sequential therapy is desirable. Our objective was to assess the cost-effectiveness of the 5-year upfront and sequential tamoxifen (tam) and ai hormonal strategies currently used for treating patients with estrogen receptor (er)-positive early breast cancer. METHODS: The cost-effectiveness analysis used a Markov model that took a Canadian health system perspective with a lifetime time horizon. The base case involved 65-year-old women with er-positive early breast cancer. Probabilistic sensitivity analyses were used to incorporate parameter uncertainties. An expected-value-of-perfect-information test was performed to identify future research directions. Outcomes were quality-adjusted life-years (qalys) and costs. RESULTS: The sequential tam-ai strategy was less costly than the other strategies, but less effective than upfront ai and more effective than upfront tam. Upfront ai was more effective and less costly than upfront tam because of less breast cancer recurrence and differences in adverse events. In an exploratory analysis that included a sequential ai-tam strategy, ai-tam dominated based on small numerical differences unlikely to be clinically significant; that strategy was thus not used in the base-case analysis. CONCLUSIONS: In postmenopausal women with er-positive early breast cancer, strategies using ais appear to provide more benefit than strategies using tam alone. Among the ai-containing strategies, sequential strategies using tam and an ai appear to provide benefits similar to those provided by upfront ai, but at a lower cost.

A population-based study of the epidemiology of pancreatic cancer: a brief report.

OBJECTIVE: Administrative data are used to describe the pancreatic cancer (pcc) population. The analysis examines demographic details, incidence, site, survival, and factors influencing mortality in a cohort of individuals diagnosed with pcc. METHODS: Incident cases of pcc diagnosed in Ontario between 1 January 2004 and 31 December 2011 were extracted from the Ontario Cancer Registry. They were linked by encrypted health card number to several administrative databases to obtain demographic and mortality information. Descriptive, bivariate, and survival analyses were conducted. RESULTS: During the period of interest, 9221 new cases of pcc (4548 in men, 4673 in women) were diagnosed, for an age-adjusted standardized annual incidence in the range of 8.6-9.5 per 100,000 population. Mean age at diagnosis was 70.3 ± 12.5 years (standard deviation). Five-year survival was 7.2% (12.8% for those <60 years of age and 3.6% for those >80 years of age). Survival varied by sex, older age, rural residence, lower income, site of involvement in the pancreas, and presence of comorbidity. CONCLUSIONS: The mortality rate in pcc is exceptionally high. With an increasing incidence and a mortality positively associated with age, additional support will be needed for this highly fatal disease as demographics in Ontario continue to trend toward a higher proportion of older individuals.

The price of performance: a cost and performance analysis of the implementation of cell-free fetal DNA testing for Down syndrome in Ontario, Canada.

OBJECTIVE: To examine the cost and performance implications of introducing cell-free fetal DNA (cffDNA) testing within modeled scenarios in a publicly funded Canadian provincial Down syndrome (DS) prenatal screening program. METHOD: Two clinical algorithms were created: the first to represent the current screening program and the second to represent one that incorporates cffDNA testing. From these algorithms, eight distinct scenarios were modeled to examine: (1) the current program (no cffDNA), (2) the current program with first trimester screening (FTS) as the nuchal translucency-based primary screen (no cffDNA), (3) a program substituting current screening with primary cffDNA, (4) contingent cffDNA with current FTS performance, (5) contingent cffDNA at a fixed price to result in overall cost neutrality,(6) contingent cffDNA with an improved detection rate (DR) of FTS, (7) contingent cffDNA with higher uptake of FTS, and (8) contingent cffDNA with optimized FTS (higher uptake and improved DR). RESULTS: This modeling study demonstrates that introducing contingent cffDNA testing improves performance by increasing the number of cases of DS detected prenatally, and reducing the number of amniocenteses performed and concomitant iatrogenic pregnancy loss of pregnancies not affected by DS. Costs are modestly increased, although the cost per case of DS detected is decreased with contingent cffDNA testing. CONCLUSION: Contingent models of cffDNA testing can improve overall screening performance while maintaining the provision of an 11- to 13-week scan. Costs are modestly increased, but cost per prenatally detected case of DS is decreased.

Meaningful patient representation informing Canada's cancer drug funding decisions: views of patient representatives on the Pan-Canadian Oncology Drug Review.

In this interview with the patient representatives on the Expert Review Committee (perc) of the Pan-Canadian Oncology Drug Review (pcodr), those representatives offer their views about how to be a valuable contributing member of Canada's national cancer drug funding recommendation committee. The article seeks to inform readers, and especially clinicians, about pcodr from the perspective of the patient representatives.

Population-based utilization of radiation therapy by a Canadian breast cancer cohort.

We examined trends in radiation therapy (rt) utilization by a population-based breast cancer cohort in Ontario. The provincial cancer registry provided a breast cancer cohort based on diagnosis dates from April 1, 2005, to March 31, 2010. Staging information was also available. The cohort was then linked, by encrypted health card number, to linkable administrative datasets, including rt utilization. The average age in the identified female breast cancer cohort (n = 39,656) was 61.6 ± 14.0 years. Almost two thirds of the patients (n = 25,225) received rt, and staging information was available for 22,988 patients (9541 stage i, 8516 stage ii, 4050 stage iii, and 881 stage iv). The average number of rt courses received by the patients was 1.4 ± 0.7 for stage i, 1.8 ± 1.1 for stage ii, 2.5 ± 1.3 for stage iii, and 2.8 ± 2.4 for stage iv. The ratio of conventional rt to intensity-modulated rt was 70.9%:16.6% for stage i, 71.6%:11.3% for stage ii, 74.6%:4.6% for stage iii, and 89.6%:2.2% for stage iv. From 2005 to 2010, almost two thirds of a Canadian female breast cancer cohort received rt, and the average number of courses increased with disease severity. A similar trend was observed with the type of rt (use of conventional rt increased with disease severity). The next step is to apply unit costs to the number of fractions and to obtain rt planning and radiation therapist times.

Health system costs for stage-specific breast cancer: a population-based approach.

OBJECTIVE: The objective of the present analysis was to determine the publicly funded health care costs associated with the care of breast cancer (bca) patients by disease stage. METHODS: Incident cases of female invasive bca (2005-2009) were extracted from the Ontario Cancer Registry and linked to administrative datasets from the publicly funded system. The type and use of health care services were stratified by disease stage over the first 2 years after diagnosis. Mean costs and costs by type of clinical resource used in the care of bca patients were compared with costs for a matched control group. The attributable cost for the 2-year time horizon was determined in 2008 Canadian dollars. RESULTS: This cohort study involved 39,655 patients with bca and 190,520 control subjects. The average age in those groups was 61.1 and 60.9 years respectively. Most bca patients were classified as either stage i (34.4%) or stage ii (31.8%). Of the bca cohort, 8% died within the first 2 years after diagnosis. The overall mean cost per bca case from a public payer perspective in the first 2 years after diagnosis was $41,686. Over the 2-year time horizon, the mean cost increased by stage: i, $29,938; ii, $46,893; iii, $65,369; and iv, $66,627. The attributable cost of bca was $31,732. Cost drivers were cancer clinic visits, physician billings, and hospitalizations. CONCLUSIONS: Costs of care increased by stage of bca. Cost drivers were cancer clinic visits, physician billings, and hospitalizations. These data will assist planning and decision-making for the use of limited health care resources.

Examining evidence for a relationship between human-animal interactions and common mental disorders during the COVID-19 pandemic: a systematic literature review.

Introduction: COVID-19 lockdowns, shelter in place, closures of transportation and mental health services, and dearth of mental health providers created new barriers to obtaining support for mental health needs at a time of increased rates of anxiety and depression. During the pandemic, a record number of households owned and adopted pets, opening a potential avenue to investigate the relationship between pets and mental health. This systematic literature review examined the question: What is the evidence for a relationship between human-animal interaction and/or animal ownership and common mental disorders among adults who interacted with pets compared to adults who did not during the COVID-19 pandemic? Methods: To address this question, four databases were searched: Medline, PsycINFO, Web of Science, and SCOPUS for peer-reviewed literature published between 2020 and July 2023. Of the 1,746 articles identified by the searches, 21 studies were included in this review. Results: Results suggest that there exists a relationship between animal ownership and strong pet attachment and pet interaction, though the directionality of the relationship was not investigated by the included studies. There was an association between having a stronger relationship with a pet and lower feelings of depression and other mental health symptoms. There was also evidence of an association between anxiety and higher levels of animal attachment. Conclusion: Understanding the association between human-animal interaction and common mental disorders may be helpful to clinicians assessing the mental health of clients. Clinicians may glean additional insight about stressors, risk factors, social supports, and lifestyle of clients based on the client's status as a pet owner. Future research could further explore the direction of the causal relationship of human-animal interaction and/or animal ownership on common mental disorders; this could further inform how the HAI relationship can be used to support clients with mental health struggles.

Population-based home care services in breast cancer: utilization and costs.

OBJECTIVE: To determine utilization and costs of home care services (hcs) for individuals with a diagnosis of breast cancer (bc). METHODS: Incident cases of invasive bc in women were extracted from the Ontario Cancer Registry (2005-2009) and linked with other Ontario health care administrative databases. Control patients were selected from the population of women never diagnosed with any type of cancer. The types and proportions of hcs used were determined and stratified by disease stage. Attributable home care utilization and costs for bc patients were determined. Factors associated with hcs costs were assessed using regression analysis. RESULTS: Among the 39,656 bc and 198,280 control patients identified (median age: 61.6 years for both), 75.4% of bc patients used hcs (62.1% stage i; 85.7% stage ii; 94.6% stage iii; 79.1% stage iv) compared with 14.6% of control patients. The number of hcs used per patient-year were significantly higher for the bc patients than for the control patients (14.97 vs. 6.13, p < 0.01), resulting in higher costs per patient-year ($1,210 vs. $325; $885 attributable cost to bc, p < 0.01). The number of hcs utilized and the associated costs increased as the bc stage increased. In contrast, hcs costs decreased as income increased and as previous health care exposure decreased. INTERPRETATION: Patients with bc used twice as many hcs, resulting in costs that were almost 4 times those observed in a matched control group. Less than an additional $1000 per bc patient per year were spent on hcs utilization in the study population.

Omission of Breast Radiotherapy in Low-risk Luminal A Breast Cancer: Impact on Health Care Costs.

AIMS: The economic burden of cancer care is substantial, including steep increases in costs for breast cancer management. There is mounting evidence that women age ≥ 60 years with grade I/II T1N0 luminal A (ER/PR+, HER2- and Ki67 ≤ 13%) breast cancer have such low local recurrence rates that adjuvant breast radiotherapy might offer limited value. We aimed to determine the total savings to a publicly funded health care system should omission of radiotherapy become standard of care for these patients. MATERIALS AND METHODS: The number of women aged ≥ 60 years who received adjuvant radiotherapy for T1N0 ER+ HER2- breast cancer in Ontario was obtained from the provincial cancer agency. The cost of adjuvant breast radiotherapy was estimated through activity-based costing from a public payer perspective. The total saving was calculated by multiplying the estimated number of luminal A cases that received radiotherapy by the cost of radiotherapy minus Ki-67 testing. RESULTS: In 2010, 748 women age ≥ 60 years underwent surgery for pT1N0 ER+ HER2- breast cancer; 539 (72%) underwent adjuvant radiotherapy, of whom 329 were estimated to be grade I/II luminal A subtype. The cost of adjuvant breast radiotherapy per case was estimated at $6135.85; the cost of Ki-67 at $114.71. This translated into an annual saving of about $2.0million if radiotherapy was omitted for all low-risk luminal A breast cancer patients in Ontario and $5.1million across Canada. CONCLUSION: There will be significant savings to the health care system should omission of radiotherapy become standard practice for women with low-risk luminal A breast cancer.

Using forecasting models to estimate the effects of changes in the composition of claims for selective serotonin reuptake inhibitors on expenditures.

BACKGROUND: The use of selective serotonin reuptake inhibitors (SSRIs) as antidepressant therapy has increased considerably since the introduction of fluoxetine in 1989. By 1999, 3 of the 4 available SSRIs were among the top 10 most frequently used drugs in the United States. In addition, SSRIs were one of the major contributors to the growth in psychotropic medication expenditures during the past 5 years. OBJECTIVE: The purpose of this article was to examine the utilization patterns of the 4 most commonly used SSRIs and their contribution to rising antidepressant medication expenditures among claimants in a publicly funded drug program. Using the results of forecasting models, we explored possible ways to control these growing expenditures. METHODS: Cross-sectional antidepressant claims and expenditure data from the Ontario Drug Benefits program for 1992 to 1998 were examined. Five scenarios were modeled in which future SSRI expenditures and claims were predicted using exponential smoothing models. RESULTS: If the historical patterns of use continued, a 20% increase in the 1998 level of expenditures was expected to occur by the year 2000. Predicted expenditures are sensitive to the composition of the SSRI claims. Exclusive use of 1 of the 4 major SSRIs (fluvoxamine, fluoxetine, paroxetine, and sertraline) could decrease projected expenditures by 30% or increase them by 11%. An "equal shares" approach, in which each of the 4 SSRIs are used in equal proportions in the population, may reduce expenditures by approximately 8%. CONCLUSIONS: The current trends in the utilization data suggest that sertraline and paroxetine are being used as first-line treatments. The results of the forecasting models suggest that growing expenditures could be curbed if these 2 antidepressants were not used in that manner. Short of limiting the drugs available on benefit formularies, there may be a way to control costs through the use of a prescribing algorithm. Although our results support the use of fluoxetine for first-line SSRI treatment as a cost-control measure, we do not definitively recommend its adoption. These findings contribute to the discussion about using fixed versus flexible formularies as a potential cost-control mechanism.

Use and costs of ambulatory care services among Medicare enrollees with schizophrenia.

OBJECTIVE: The objective of this study was to identify predictors of the use and cost of ambulatory care services among Medicare recipients with schizophrenia. METHODS: The design was a cross-sectional analysis of Medicare claims in 1991. The study subjects were a 5 percent random sample of all persons in the United States who had at least one Medicare service claim in 1991 and who were diagnosed as having schizophrenia in any care setting. Outcome measures included use and cost of any ambulatory care service, individual therapy, psychiatric somatotherapy, group therapy, or family therapy. RESULTS: For nearly 25 percent of the total sample of 12,440, no claims were filed for ambulatory care services in 1991. The mean+/-SD number of ambulatory care visits during the year was 7.9+/-21. The most frequently used type of therapy was individual therapy (5+/-14 visits). The mean+/-SD yearly cost of care for persons who received ambulatory care services was $470+/-$1,028. Among persons under 65 years of age, Caucasians were about 1.5 times as likely as African Americans to have received an ambulatory care service and 1.3 times as likely to have received individual therapy. Persons who were 65 or older were less likely to have received any service. Among service recipients, costs of care were lower for African Americans and for older people. CONCLUSIONS: The use of Medicare-funded ambulatory care services by persons with schizophrenia varied by race and age. Further investigation is required to determine whether subgroups of individuals who do not have additional insurance coverage or access to services are receiving substandard care.