Accuracy, risk and the intrinsic value of diagnostic imaging: a review of the cost-utility literature

Toward Alignment in the Reporting of Economic Evaluations of Diagnostic Tests and Biomarkers: The AGREEDT Checklist

Objectives. General frameworks for conducting and reporting health economic evaluations are available but not specific enough to cover the intricacies of the evaluation of diagnostic tests and biomarkers. Such evaluations are typically complex and model-based because tests primarily affect health outcomes indirectly and real-world data on health outcomes are often lacking. Moreover, not all aspects relevant to the evaluation of a diagnostic test may be known and explicitly considered for inclusion in the evaluation, leading to a loss of transparency and replicability. To address this challenge, this study aims to develop a comprehensive reporting checklist. Methods. This study consisted of 3 main steps: 1) the development of an initial checklist based on a scoping review, 2) review and critical appraisal of the initial checklist by 4 independent experts, and 3) development of a final checklist. Each item from the checklist is illustrated using an example from previous research. Results. The scoping review followed by critical review by the 4 experts resulted in a checklist containing 44 items, which ideally should be considered for inclusion in a model-based health economic evaluation. The extent to which these items were included or discussed in the studies identified in the scoping review varied substantially, with 14 items not being mentioned in ≥47 (75%) of the included studies. Conclusions. The reporting checklist developed in this study may contribute to improved transparency and completeness of model-based health economic evaluations of diagnostic tests and biomarkers. Use of this checklist is therefore encouraged to enhance the interpretation, comparability, and—indirectly—the validity of the results of such evaluations.

Use of Shoulder Imaging in the Outpatient Setting: A Pilot Study

PURPOSE

Characterize the clinical utility of diagnostic shoulder imaging modalities commonly used in the outpatient workup of shoulder pain.

MATERIALS/METHODS

Retrospective review of adults imaged for outpatient shoulder pain from 1/1/2013 to 9/1/2015. To be categorized as "useful", a study had to meet one of the following criteria: change the clinical diagnosis or treatment plan, provide a final diagnosis, or guide definitive treatment. A utility score was assigned to each study based on the number of utility criteria met (range 0-4). A score of 1 was considered low utility; a score of greater than or equal to 2 was considered high utility. Statistical analysis included binary logistic regression and generalized estimating equations.

RESULTS

210 subjects (65% male); mean age 47 (range 18-84), underwent 302 imaging studies (159 X-ray, 137 MRI, 2 CT, 4 ultrasound) during the study period. 92.1% of all studies met minimum criteria for utility (score >1). Most commonly, diagnostic studies obtained during the outpatient workup of shoulder pain were found to guide definitive treatment (70.5%) or provide a final diagnosis (53%). Most X-rays were categorized as no or low utility (85.5%). 97.8% of the MRI studies were categorized as useful with most being high utility (73%). Overall, MRI was the most useful modality in all clinical scenarios (P = 0.002) and more likely to be high utility (P < 0.001) compared to X-rays. None of the investigated patient or injury characteristics were significant predictors of useful imaging.

CONCLUSION

Our study suggests that both radiographs and MRI are useful in the evaluation of adult unilateral shoulder pain in the outpatient setting. MRI appears to be the most useful imaging modality in terms of helping guide diagnosis and treatment selection. This serves as a potential first step towards the development of evidence based imaging algorithms that can be used and tested in future studies.

Systematic Review of Health Economic Evaluations of Diagnostic Tests in Brazil: How accurate are the results?

The aim of this study is to identify and characterize the health economic evaluations (HEEs) of diagnostic tests conducted in Brazil, in terms of their adherence to international guidelines for reporting economic studies and specific questions in test accuracy reports. We systematically searched multiple databases, selecting partial and full HEEs of diagnostic tests, published between 1980 and 2013. Two independent reviewers screened articles for relevance and extracted the data. We performed a qualitative narrative synthesis. Forty-three articles were reviewed. The most frequently studied diagnostic tests were laboratory tests (37.2%) and imaging tests (32.6%). Most were non-invasive tests (51.2%) and were performed in the adult population (48.8%). The intended purposes of the technologies evaluated were mostly diagnostic (69.8%), but diagnosis and treatment and screening, diagnosis, and treatment accounted for 25.6% and 4.7%, respectively. Of the reviewed studies, 12.5% described the methods used to estimate the quantities of resources, 33.3% reported the discount rate applied, and 29.2% listed the type of sensitivity analysis performed. Among the 12 cost-effectiveness analyses, only two studies (17%) referred to the application of formal methods to check the quality of the accuracy studies that provided support for the economic model. The existing Brazilian literature on the HEEs of diagnostic tests exhibited reasonably good performance. However, the following points still require improvement: 1) the methods used to estimate resource quantities and unit costs, 2) the discount rate, 3) descriptions of sensitivity analysis methods, 4) reporting of conflicts of interest, 5) evaluations of the quality of the accuracy studies considered in the cost-effectiveness models, and 6) the incorporation of accuracy measures into sensitivity analyses.

Toward a Framework for Benefit-Risk Assessment in Diagnostic Imaging: Identifying Scenario-specific Criteria

RATIONALE AND OBJECTIVES

Diagnostic imaging has many effects and there is no common definition of value in diagnostic radiology. As benefit-risk trade-offs are rarely made explicit, it is not clear which framework is used in clinical guideline development. We describe initial steps toward the creation of a benefit-risk framework for diagnostic radiology.

MATERIALS AND METHODS

We performed a literature search and an online survey of physicians to identify and collect benefit-risk criteria (BRC) relevant to diagnostic imaging tests. We operationalized a process for selection of BRC with the use of four clinical use case scenarios that vary by diagnostic alternatives and clinical indication. Respondent BRC selections were compared across clinical scenarios and between radiologists and nonradiologists.

RESULTS

Thirty-six BRC were identified and organized into three domains: (1) those that account for differences attributable only to the test or device (n = 17); (2) those that account for clinical management and provider experiences (n = 12); and (3) those that capture patient experience (n = 7). Forty-eight survey participants selected 22 criteria from the initial list in the survey (9-11 per case). Engaging ordering physicians increased the number of criteria selected in each of the four clinical scenarios presented. We developed a process for standardizing selection of BRC in guideline development.

CONCLUSION

These results suggest that a process relying on elements of comparative effectiveness and the use of standardized BRC may ensure consistent examination of differences among alternatives by way of making explicit implicit trade-offs that otherwise enter the decision-making space and detract from consistency and transparency. These findings also highlight the need for multidisciplinary teams that include input from ordering physicians.

Thoracic ultrasound: An adjunctive and valuable imaging tool in emergency, resource-limited settings and for a sustainable monitoring of patients

Imaging workup of patients referred for elective assessment of chest disease requires an articulated approach: Imaging is asked for achieving timely diagnosis. The concurrent or subsequent use of thoracic ultrasound (TUS) with conventional (chest X-rays-) and more advanced imaging procedures (computed tomography and magnetic resonance imaging) implies advantages, limitations and actual problems. Indeed, despite TUS may provide useful imaging of pleura, lung and heart disease, emergency scenarios are currently the most warranted field of application of TUS: Pleural effusion, pneumothorax, lung consolidation. This stems from its role in limited resources subsets; actually, ultrasound is an excellent risk reducing tool, which acts by: (1) increasing diagnostic certainty; (2) shortening time to definitive therapy; and (3) decreasing problems from blind procedures that carry an inherent level of complications. In addition, paediatric and newborn disease are particularly suitable for TUS investigation, aimed at the detection of congenital or acquired chest disease avoiding, limiting or postponing radiological exposure. TUS improves the effectiveness of elective medical practice, in resource-limited settings, in small point of care facilities and particularly in poorer countries. Quality and information provided by the procedure are increased avoiding whenever possible artefacts that can prevent or mislead the achievement of the correct diagnosis. Reliable monitoring of patients is possible, taking into consideration that appropriate expertise, knowledge, skills, training, and even adequate equipment’s suitability are not always and everywhere affordable or accessible. TUS is complementary imaging procedure for the radiologist and an excellent basic diagnostic tool suitable to be shared with pneumologists, cardiologists and emergency physicians.

Health Technology Assessment - science or art?

The founding disciplines of HTA are clearly scientific, and have been firmly based among the natural sciences. However, common definitions of HTA indicate that HTA is something more than the "pure application of science". This article investigates whether this "something" also makes HTA an art. The question of whether HTA is a science or an art is pursued in two specific and historically rich directions. The first is whether HTA is an art in the same way that medicine is described as an art. It has been argued extensively that medicine is based on two different and partly incompatible cultures, i.e., the natural sciences and humanities. Medicine is based on disciplines within the natural sciences, while its value judgments have been placed in the humanities camp. This dichotomy is present in HTA as well, and the first part of the investigation illustrates how HTA is an art in terms of its inherent and constitutive value-judgments. The second part of the science/art-scrutiny leads us to the ancient (Hippocratic) concept of art, téchne, where we find an etymological and a conceptual link between HTA and art. It demonstrates HTA is not an arbitrary process, even though it involves value judgments and relates complex decision making processes. As an art (téchne) HTA has a specific subject matter, requires inquiry and mastery of general rational principles, and is oriented to a specific end. In conclusion, the science-or-art-question makes sense in two specific perspectives, illustrating that HTA is a science based art. This has implications for the practice of HTA, for its education, and for the status of its results.