Table 7Evidence Base

CriterionKnowledge Gaps
Size of the affected populationSurveillance is common in the realm of infectious disease, but point prevalence estimates were not available for the clinical conditions included in this report.
Impact on health disparitiesWhile health disparity reduction has been a health sector priority for decades,14 we struggled to find data for any of the population groups identified as having a disproportionate burden. In the absence of these data, no informed comment could be made as to whether a supply disruption would reduce or increase health disparities.
Relative acceptability of the test to patientsFew studies16,17 have investigated the acceptability of 99mTc-based tests, compared with the alternatives, from the patient’s perspective. The two referenced in the evidence reports prepared by CADTH included 41 patients and 63 patients, respectively.
Relative diagnostic accuracy of the testThe bulk of the evidence presented to MIIMAC was about the diagnostic accuracy of the various tests. However, the evidence base is not as robust as it is for other health technologies, such as pharmaceuticals.
Relative risks associated with the testThere were discrepancies in the reported radiation dose associated with the nuclear and non-nuclear diagnostic imaging procedures being evaluated.
Relative availability of expertise and experience required for the testThis criterion was informed primarily by expert opinion. While the NPS captures the number of physicians and specialists in Canada, expert judgment was required to estimate how many of a given specialty might have the expertise required to perform a given procedure. For select non-imaging alternatives, some published information was available regarding competency to perform the procedure.
Accessibility of alternativesThis criterion was informed primarily by expert opinion. While the number of devices across the country, province, and territory is made available by CIHI, expert judgment was required to estimate the capacity of the system to accommodate increased demand for the alternatives.

CADTH = Canadian Agency for Drugs and Technologies in Health; CIHI = Canadian Institute of Health Information; MIIMAC = Medical Isotopes and Imaging Modalities Advisory Committee; NPS = National Physician Survey; 99mTc = technetium-99m.


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Optimizing Health System Use of Medical Isotopes and Other Imaging Modalities [Internet].
Mujoomdar M, Russell E, Dionne F, et al.
Copyright © 2012 CADTH.

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