record linkages are often performed by in-house registry staff with Internal Review Board (IRB) approval and are protected by state registry law. While these issues will need to be resolved, there are examples of successful data aggregations and linkages—the NCI has pooled cancer data from its participating registries and linked them to Medicare files while adhering to strict privacy and confidentiality rules (see description of the Medicare-SEER linkage studies in Chapter 4).
Relative to the ideal described in Chapter 2, current data systems applicable to cancer care quality assessments have serious shortcomings. No well-established set of quality of care measures exists; consequently, quality assessment initiatives have faced the task of defining such measures for themselves. Quality improvement initiatives have been impeded both by the absence of good cancer care measures and limitations of available data systems. Standards are lacking for reporting factors that are needed in the measurement of the quality of cancer care, for example, stage and comorbidity. Providers do not yet use computer-based patient records, and abstraction of quality information from medical records is time consuming, expensive, and labor intensive. Currently, no data systems are in place with which to make national inferences about the quality of cancer care, and providers do not have benchmarks or targets for gauging their performance relative to others. Despite these shortcomings, there is great potential for enhancing current systems to provide better information on the quality of cancer care.