Evidence-based risk assessment in noninvasive imaging

Assessment of important clinical and economic outcomes has become central t o the evaluation of patient care. Outcome research is deeply rooted in epid emiology, including the use of multivariable, risk-adjusted regression anal ysis. In our current health care environment, these methods are increasingl y being used to assess the quality of care and to profile physicians and la boratories. Nuclear medicine physicians therefore need to better understand outcome methodologies in order to evaluate patient outcomes, develop guide lines, and decide on patient management. Methods: This review describes the methods of assessing the diagnostic and prognostic value of nuclear medici ne techniques and, briefly, the methodologic limitations of sample size, fr equency and type of events, and follow-up periods and the incremental value of imaging. Also described are logistic regression and Cox proportional ha zards modeling. Models for risk assessment are designed to identify whether patients require conservative (i.e., low-risk) or aggressive (i.e., high-r isk) treatment. Treatment selection is currently based on risk assessment a nd the formation of an integrated, empiric risk stratification algorithm of care. This review also includes the methods of assessing economic effectiv eness and quality-of-life issues for patients examined with nuclear medicin e techniques. Conclusion: In this era of constrained resources, low-cost ou t patient-based care may be of increasing importance. High-quality evidence of the clinical and economic outcome of nuclear imaging is essential for h elping health care providers and payers assess its value.