OPPORTUNITIES AND CHALLENGES IN USING ADMINISTRATIVE DATA FOR CROSS-COUNTRY COMPARISONS OF HEALTH CARE COSTS

Purpose:    To compare end-of-life health care costs in patients with non-small cell lung cancer (NSCLC) in Ontario, Canada, and the United States (US) Medicare program using cancer registry and administrative data.

Method:    Two multidisciplinary teams collaborated to define comparable cohorts, health care services, and analyses. Patients with NSCLC who died from cancer in 2001-2005 were selected from the Ontario Cancer Registry and the US SEER cancer registry linked to Medicare claims. Inclusion criteria: survival >30 days post-diagnosis; age >65.5 at death; no lung cancer surgery within 1 year post-diagnosis (proxy for advanced stage, not recorded in Ontario data).    Ontario administrative databases track service delivery. US Medicare claims are recorded in files submitted by hospitals, physicians, and other providers. Services categorized differently by Medicare than in Ontario data were re-defined for comparability. Eg., Ontario combined costs for adjoining ER visits and hospitalizations, and costed stand-alone ER visits separately. Chemotherapy drug, physician, equipment, and overhead costs are claimed separately in Medicare. Ontario distinguished physician, some expensive drugs, and all other costs.  Resources that could not be costed comparatively were excluded; eg. outpatient prescription drugs, medical equipment. Examples of methods are below.          

Service	SEER-Medicare files	Ontario
		Data	costing
hospitalizations	MEDPAR	CIHI Discharge Abstract Database	resource intensity weight * cost per weighted case
emergency room (ER)	Outpatient	National Ambulatory Care Reporting System  (NACRS)
chemotherapy	Carrier, Outpatient	NACRS
expensive chemotherapy drugs	Carrier, Outpatient	New Drug Funding Program	drug costs in data
Physician services	Carrier	Claims History Database of the Ontario Health Insurance Plan	fee-for-service claims

    We computed mean resource-specific and total 30-day costs for 6 months before death, excluding pre-diagnosis, in USD2009, using Purchasing Power Parity for health to convert from CAD.

Result:    In the month before death, mean total costs in Ontario were $11,538 and Medicare payments were $9,556. Higher US chemotherapy payments were balanced by higher Ontario inpatient costs.  Estimates exclude patient out-of-pocket costs or payments from other insurers, approximately 40% of US and 5% of Ontario total direct medical costs for these resources.

Conclusion:    Cross-country comparisons require significant effort, and knowledge of reimbursement policies and databases, to define similar patients, services, and costs. Some cannot be compared. Despite challenges, such collaborations are underway and offer rich opportunities to improve estimation of international cancer costs.