Setting high-impact clinical research priorities for the Society for Vascular Surgery

Patient-Centered Research and Innovation in Nephrology

Patient involvement in research can improve the relevance of research, consequently enhancing the recruitment, retention, and uptake of interventions and policies impacting patient outcomes. Despite this, patients are not often involved in the design and conduct of research. The research agenda and innovations are frequently determined by the interest of health and industry professionals rather than proactively aligning with the priorities of patients. It is now being encouraged and recommended to engage patients in research priority setting to ensure interventions and trials report outcomes valuable to patients, moving away from a history of overlooking the outcomes that reflect the feel and function of patients. Involving patients ensures constant innovative research in nephrology, as this broader depth of evidence fortifies reliability and validity through knowledge gained from lived experience. Findings from such research can enhance clinical practice and strengthen decision-making and policy to support better outcomes. We aim to outline principles and strategies for patient involvement in research, including setting research priorities, identifying and designing interventions, selecting outcomes, and disseminating and translating research. Principles and strategies including engagement, education and training, empowerment, and connection and community provide guidance in patient involvement. There are increasing efforts to involve patients across all stages of research including setting research priorities. Efforts are rising to involve patients across all stages of research including priority setting, identifying and designing interventions, selecting outcomes, and dissemination and translation. Patient involvement throughout the research cycle drives innovative investigations ensuring funding, efforts, and resources are directed toward priorities of patients, contributing to catalyst advancements in care and outcomes.

Recombinant Interleukin-19 Suppresses the Formation and Progression of Experimental Abdominal Aortic Aneurysms

Background Interleukin-19 is an immunosuppressive cytokine produced by immune and nonimmune cells, but its role in abdominal aortic aneurysm (AAA) pathogenesis is not known. This study aimed to investigate interleukin-19 expression in, and influences on, the formation and progression of experimental AAAs. Methods and Results Human specimens were obtained at aneurysm repair surgery or from transplant donors. Experimental AAAs were created in 10- to 12-week-old male mice via intra-aortic elastase infusion. Influence and potential mechanisms of interleukin-19 treatment on AAAs were assessed via ultrasonography, histopathology, flow cytometry, and gene expression profiling. Immunohistochemistry revealed augmented interleukin-19 expression in both human and experimental AAAs. In mice, interleukin-19 treatment before AAA initiation via elastase infusion suppressed aneurysm formation and progression, with attenuation of medial elastin degradation, smooth-muscle depletion, leukocyte infiltration, neoangiogenesis, and matrix metalloproteinase 2 and 9 expression. Initiation of interleukin-19 treatment after AAA creation limited further aneurysmal degeneration. In additional experiments, interleukin-19 treatment inhibited murine macrophage recruitment following intraperitoneal thioglycolate injection. In classically or alternatively activated macrophages in vitro, interleukin-19 downregulated mRNA expression of inducible nitric oxide synthase, chemokine C-C motif ligand 2, and metalloproteinases 2 and 9 without apparent effect on cytokine-expressing helper or cytotoxic T-cell differentiation, nor regulatory T cellularity, in the aneurysmal aorta or spleen of interleukin-19-treated mice. Interleukin-19 also suppressed AAAs created via angiotensin II infusion in hyperlipidemic mice. Conclusions Based on human evidence and experimental modeling observations, interleukin-19 may influence the development and progression of AAAs.

Establishing a carotid artery stenosis disease cohort for comparative effectiveness research using natural language processing

OBJECTIVE

Investigation of asymptomatic carotid stenosis treatment is hindered by the lack of a contemporary population-based disease cohort. We describe the use of natural language processing (NLP) to identify stenosis in patients undergoing carotid imaging.

METHODS

Adult patients with carotid imaging between 2008 and 2012 in a large integrated health care system were identified and followed through 2017. An NLP process was developed to characterize carotid stenosis according to the Society of Radiologists in Ultrasound (for ultrasounds) and North American Symptomatic Carotid Endarterectomy Trial (NASCET) (for axial imaging) guidelines. The resulting algorithm assessed text descriptors to categorize normal/non-hemodynamically significant stenosis, moderate or severe stenosis as well as occlusion in both carotid ultrasound (US) and axial imaging (computed tomography and magnetic resonance angiography [CTA/MRA]). For US reports, internal carotid artery systolic and diastolic velocities and velocity ratios were assessed and matched for laterality to supplement accuracy. To validate the NLP algorithm, positive predictive value (PPV or precision) and sensitivity (recall) were calculated from simple random samples from the population of all imaging studies. Lastly, all non-normal studies were manually reviewed for confirmation for prevalence estimates and disease cohort assembly.

RESULTS

A total of 95,896 qualifying index studies (76,276 US and 19,620 CTA/MRA) were identified among 94,822 patients including 1059 patients who underwent multiple studies on the same day. For studies of normal/non-hemodynamically significant stenosis arteries, the NLP algorithm showed excellent performance with a PPV of 99% for US and 96.5% for CTA/MRA. PPV/sensitivity to identify a non-normal artery with correct laterality in the CTA/MRA and US samples were 76.9% (95% confidence interval [CI], 74.1%-79.5%)/93.1% (95% CI, 91.1%-94.8%) and 74.7% (95% CI, 69.3%-79.5%)/94% (95% CI, 90.2%-96.7%), respectively. Regarding cohort assembly, 15,522 patients were identified with diseased carotid artery, including 2674 exhibiting equal bilateral disease. This resulted in a laterality-specific cohort with 12,828 moderate, 5283 severe, and 1895 occluded arteries and 326 diseased arteries with unknown stenosis. During follow-up, 30.1% of these patients underwent 61,107 additional studies.

CONCLUSIONS

Use of NLP to detect carotid stenosis or occlusion can result in accurate exclusion of normal/non-hemodynamically significant stenosis disease states with more moderate precision with lesion identification, which can substantially reduce the need for manual review. The resulting cohort allows for efficient research and holds promise for similar reporting in other vascular diseases.

Current pharmacological management of aortic aneurysm

ABSTRACT

Aortic aneurysm (AA) remains one of the primary causes of death worldwide. Of the major treatments, prophylactic operative repair is used for AA to avoid potential aortic dissection (AD) or rupture. To halt the development of AA and alleviate its progression into AD, pharmacological treatment has been investigated for years. Currently, β-adrenergic blocking agents, losartan, irbesartan, angiotensin-converting-enzyme inhibitors, statins, antiplatelet agents, doxycycline, and metformin have been investigated as potential candidates for preventing AA progression. However, the paradox between preclinical successes and clinical failures still exists, with no medical therapy currently available for ideally negating the disease progression. This review describes the current drugs used for pharmacological management of AA and their individual potential mechanisms. Preclinical models for drug screening and evaluation are also discussed to gain a better understanding of the underlying pathophysiology and ultimately find new therapeutic targets for AA.

[Reperfusion syndrome: state of the art]

Reperfusion syndrome is a complex series of clinical manifestations resulting from restoration of blood flow to previously ischaemic tissues. It is accompanied by damage to cells, tissues and organs at various levels, followed by the development of multiple organ failure. This review deals with the main pathophysiological mechanisms of the development of reperfusion syndrome in lesions of cardiac, cerebral and lower-limb vessels. Oxidative stress is considered to be the most important marker of ischaemia-reperfusion injury irrespective of the type of tissues affected. Presented herein are the data on contemporary possibilities of influencing various stages and components of the development of reperfusion injury by means of drug therapy, demonstrating that due to the importance of oxidative stress as a key link of reperfusion injury, antioxidant therapy should be the main component of prevention and treatment of reperfusion injury.

Background and Proposed Design for a Metformin Abdominal Aortic Aneurysm Suppression Trial

Abdominal aortic aneurysm (AAA) may lead to rupture and death if left untreated. While endovascular or surgical repair is generally recommended for AAA greater than 5–5.5 cm, the vast majority of aneurysms detected by screening modalities are smaller than this threshold. Once discovered, there would be a significant potential benefit in suppressing the growth of these small aneurysms in order to obviate the need for repair and mitigate rupture risk. Patients with diabetes, in particular those taking the oral hypoglycaemic medication metformin, have been shown to have lower incidence, growth rate, and rupture risk of AAA. Metformin therefore represents a widely available, non-toxic, potential inhibitor of AAA growth, but thus far no prospective clinical studies have evaluated this. Here, we present the background, rationale, and design for a randomised, double-blind, placebo-controlled clinical trial of metformin for growth suppression in patients with small AAA.

Metformin prescription status and abdominal aortic aneurysm disease progression in the U.S. veteran population

BACKGROUND

Identification of a safe and effective medical therapy for abdominal aortic aneurysm (AAA) disease remains a significant unmet medical need. Recent small cohort studies indicate that metformin, the world's most commonly prescribed oral hypoglycemic agent, may limit AAA enlargement. We sought to validate these preliminary observations in a larger cohort.

METHODS

All patients with asymptomatic AAA disease managed in the Veterans Affairs Health Care System between 2003 and 2013 were identified by International Classification of Diseases, Ninth Revision codes. Those with a concomitant diagnosis of diabetes mellitus who also received two or more abdominal imaging studies (computed tomography, magnetic resonance imaging, or ultrasound) documenting the presence and size of an AAA, separated by at least 1 year, were included for review. Maximal AAA diameters were determined from radiologic reports. Further data acquisition was censored after surgical AAA repair, when performed. Comorbidities, active smoking status, and outpatient medication records (within 6 months of AAA diagnosis) were also queried. Yearly AAA enlargement rates, as a function of metformin treatment status, were compared using two statistical models expressed in millimeters per year: a multivariate linear regression (model 1) and a multivariate mixed-effects model with random intercept and random slope (model 2).

RESULTS

A total of 13,834 patients with 58,833 radiographic records were included in the analysis, with radiology imaging follow-up of 4.2 ± 2.6 years (mean ± standard deviation). The average age of the patients at AAA diagnosis was 69.8 ± 7.8 years, and 39.7% had a metformin prescription within ±6 months of AAA. The mean growth rate for AAAs in the entire cohort was 1.4 ± 2.0 mm/y by model 1 analysis and 1.3 ± 1.6 mm/y by model 2 analysis. The unadjusted mean rate of AAA growth was 1.2 ± 1.9 mm/y for patients prescribed metformin compared with 1.5 ± 2.2 mm/y for those without (P < .001), a 20% decrease. This effect remained significant when adjusted for variables relevant on AAA progression: metformin prescription was associated with a reduction in yearly AAA growth rate of -0.23 mm (95% confidence interval, -0.35 to -0.16; P < .001) by model 1 analysis and 0.20 mm/y (95% confidence interval, -0.26 to -0.14; P < .001) by model 2 analysis. A subset analysis of 7462 patients with baseline AAA size of 35 to 49 mm showed a similar inhibitory effect (1.4 ± 2.0 mm/y to 1.7 ± 2.2 mm/y; P < .001). Patients' factors associated with an increased yearly AAA growth rate were baseline AAA size, metastatic solid tumors, active smoking, chronic obstructive pulmonary disease, and chronic renal disease. Factors associated with decreased yearly AAA growth rates included prescriptions for angiotensin II type 1 receptor blockers or sulfonylureas and the presence of diabetes-related complications.

CONCLUSIONS

In a nationwide analysis of diabetic Veterans Affairs patients, prescription for metformin was associated with decreased AAA enlargement. These findings provide further support for the conduct of prospective clinical trials to test the ability of metformin to limit progression of early AAA disease.

Regional variation in patient outcomes in carotid artery disease treatment in the Vascular Quality Initiative

OBJECTIVE

Quality metrics were developed to improve outcomes after carotid artery revascularization; however, few studies have evaluated regional differences in perioperative outcomes. This study aimed to evaluate regional variation in mortality and perioperative outcomes after carotid endarterectomy (CEA) and carotid artery stenting (CAS).

METHODS

We identified all patients who underwent CEA or CAS from 2009 to 2016 in the Vascular Quality Initiative. Patients were analyzed on the basis of their symptom status. We assessed variation in perioperative outcomes using χ² analysis, Fisher exact test, and t-test, where appropriate.

RESULTS

A total of 78,467 carotid interventions were identified; 85% were CEAs, with 69% of those asymptomatic. Within CAS, 39% were asymptomatic. Perioperative stroke/death varied across regions within both CAS groups (asymptomatic, 0%-5.8% [P = .03]; symptomatic, 2.4%-8.1% [P = .1]), and several regions did not meet the American Heart Association (AHA) guidelines of 3% for asymptomatic patients and 6% for symptomatic patients, which persisted after risk adjustment. For CEA, the stroke/death rates fell within the standards set by the AHA guidelines in all regions for both the unadjusted and risk-adjusted models; however, there was significant regional variation in the cohorts (asymptomatic, 0.9%-3.1% [P < .01]; symptomatic, 1.3%-4.9% [P < .01]). Variation in 30-day mortality was significant in symptomatic patients (asymptomatic: CEA, 0%-1.3% [P = .2], CAS, 0%-2.4% [P = .2]; symptomatic: CEA, 0%-1.8% [P < .01], CAS, 0%-4.6% [P = .01]). Rates of in-hospital stroke, postoperative myocardial infarction, prolonged length of stay (>2 days), and use of intravenous blood pressure medications all varied significantly across the regions. After CEA, there was significant variation in the rates of cranial nerve injuries (asymptomatic, 0.9%-4.9% [P < .01]; symptomatic, 1.5%-7.7% [P < .01]), return to the operating room (asymptomatic, 0.9%-3.4% [P < .01]; symptomatic, 0.6%-3.4% [P = .02]), and discharge on antiplatelet and statin (asymptomatic, 75%-87% [P < .01]; symptomatic, 78%-91% [P < .01]). After CAS, significant variation was found in the rates of access site complications (asymptomatic, 2.3%-18.2% [P < .01]; symptomatic, 1.4%-16.9% [P < .01]) and discharge on dual antiplatelet therapy (asymptomatic, 79%-94% [P < .01]; symptomatic, 83%-93% [P < .01]).

CONCLUSIONS

Unwarranted regional variation exists in outcomes after carotid artery revascularization across the regions of the VQI. Significant variation was seen in a number of outcomes for which quality metrics currently exist, such as length of stay and discharge medications. In addition, after CAS, several regions failed to meet the AHA guidelines for stroke and death. Given these results, quality improvement projects should be targeted to improve adherence to current guidelines to promote best practices.

Regional variation in patient selection and treatment for carotid artery disease in the Vascular Quality Initiative

OBJECTIVE

Previous studies involving large administrative data sets have revealed regional variation in the demographics of patients selected for carotid endarterectomy (CEA) and carotid artery stenting (CAS) but lacked clinical granularity. This study aimed to evaluate regional variation in patient selection and operative technique for carotid artery revascularization using a detailed clinical registry.

METHODS

All patients who underwent CEA or CAS from 2009 to 2015 were identified in the Vascular Quality Initiative (VQI). Deidentified regional groups were used to evaluate variation in patient selection, operative technique, and perioperative management. χ² analysis was used to identify significant variation across regions.

RESULTS

A total of 57,555 carotid artery revascularization procedures were identified. Of these, 49,179 patients underwent CEA (asymptomatic: median, 56%; range, 46%-69%; P < .01) and 8376 patients underwent CAS (asymptomatic: median, 36%; range, 29%-51%; P < .01). There was significant regional variation in the proportion of asymptomatic patients being treated for carotid stenosis <70% in CEA (3%-9%; P < .01) vs CAS (3%-22%; P < .01). There was also significant variation in the rates of intervention for asymptomatic patients older than 80 years (CEA, 12%-27% [P < .01]; CAS, 8%-26% [P < .01]). Preoperative computed tomography angiography or magnetic resonance angiography in the CAS cohort also varied widely (31%-83%; P < .01), as did preoperative medical management with combined aspirin and statin (CEA, 53%-77% [P < .01]; CAS, 62%-80% [P < .01]). In the CEA group, the use of shunt (36%-83%; P < .01), protamine (32%-89%; P < .01), and patch (87%-99%; P < .01) varied widely. Similarly, there was regional variation in frequency of CAS done without a protection device (1%-8%; P < .01).

CONCLUSIONS

Despite clinical benchmarks aimed at guiding management of carotid disease, wide variation in clinical practice exists, including the proportion of asymptomatic patients being treated by CAS and preoperative medical management. Additional intraoperative variables, including the use of a patch and protamine during CEA and use of a protection device during CAS, displayed similar variation in spite of clear guidelines. Quality improvement projects could be directed toward improved adherence to benchmarks in these areas.

Management of asymptomatic carotid stenosis

With modern intensive medical therapy, the risk of ipsilateral stroke in patients with asymptomatic carotid stenosis (ACS) is below the risk of either carotid stenting or endarterectomy. Routine intervention for ACS is therefore not justified; approximately 90% of patients with ACS would be better off with intensive medical therapy. The few who could benefit can be identified by transcranial Doppler embolus detection or features of vulnerable plaque that can be imaged by 3-dimensional ultrasound, MRI or positron emission tomography/computed tomography; some of these methods are still in development.

Research priority setting in kidney disease: a systematic review

BACKGROUND

Resources for research are insufficient to cover all unanswered questions, and therefore difficult choices about allocation must be made. Recently there has been a move toward more patient-centered research. This study aims to evaluate approaches to research prioritization in kidney disease and describe research priorities of patients with kidney disease, their caregivers, the health care providers involved in their care, and policy makers.

STUDY DESIGN

Systematic review.

SETTING & POPULATION

Studies that elicited patient, caregiver, health care provider, or policy maker priorities for research in kidney disease were included.

SEARCH STRATEGY & SOURCES

MEDLINE, EMBASE, PsycINFO, and CINAHL were searched to May 2014.

ANALYTICAL APPROACH

Descriptive synthesis.

RESULTS

We identified 16 studies (n=2,365 participants) conducted in the United States, the Netherlands, Australia, Canada, and internationally. Only 4 (25%) studies explicitly involved patients. Various priority-setting methods were used, including the Delphi technique, expert panels, consensus conference, ranking or voting surveys, focus groups, and interviews, of which the process was described in detail by 11 (69%) studies. The priority areas for research most frequently identified across studies were prevention of acute kidney injury, prevention of chronic kidney disease progression, fluid and diet restrictions, improving vascular access, kidney transplant survival, access to transplantation, patient education, and psychosocial impact of chronic kidney disease.

LIMITATIONS

Most studies were conducted in high-income countries.

CONCLUSIONS

The priorities identified by kidney disease research priority-setting exercises are broad ranging, but patient involvement is uncommon and the processes often are incompletely described. Establishing research priorities using a prespecified and transparent process that engages patients, caregivers, and health care providers is needed to ensure that resources are invested to answer questions that address the shared priorities in kidney disease.

Safety and effectiveness of endovascular therapy for claudication in octogenarians

BACKGROUND

Advanced age (≥ 80 years) has been associated with adverse outcomes after lower extremity bypass for critical limb ischemia (CLI), but endovascular therapy (ET) is reported to have comparable safety across age groups. Here, we assess the safety and effectiveness of advanced age on outcomes after ET for lifestyle-limiting intermittent claudication (IC).

METHODS

A retrospective review of a prospectively maintained institutional database (2007-2012) identified all patients undergoing ET for IC. Demographics, procedural details, and outcomes were assessed via univariate analysis and multivariate Cox regression. Effectiveness was assessed across a panel of outcome metrics including the following: overall survival, freedom from major adverse limb event (MALE), and freedom from reintervention, amputation, or restenosis (RAS). Freedom from MALE + perioperative death (MALE + POD) was the primary safety end point.

RESULTS

Two hundred thirty-six patients underwent primary ET for 284 affected limbs. Of these, 46 interventions (16%) were performed in patients ≥ 80 years old. The average age of octogenarians treated was 84.4 years compared with 67.4 years among those aged <80 (P < 0.001). Compared with younger claudicants, octogenarians were less likely to have hypercholesterolemia (43.5% vs. 63.9%, P = 0.01) and more likely to deny a history of smoking (41.3% vs. 14.7%, P < 0.001). Octogenarians were also more likely to undergo interventions involving the popliteal artery (50% vs. 31.9%, P = 0.03). There were no other significant differences in demographics, comorbidities, TransAtlantic Inter-Society Consensus II classification, or treated arterial segment. Thirty-day freedom from MALE + POD was 100% in octogenarians and 99.6% in patients <80 years, with no difference between age groups. There were no differences in freedom from MALE, freedom from RAS, or overall survival at 1- and 3-year follow-up.

CONCLUSIONS

Although age >80 years has been identified as an independent risk factor for poor outcomes in the surgical treatment of CLI, our results suggest that ET for selected octogenarians with lifestyle-limiting claudication is as safe and effective as ET in younger patients. Advanced age alone should not prohibit consideration of ET for patients with IC.

Remote effects of lower limb ischemia-reperfusion: impaired lung, unchanged liver, and stimulated kidney oxidative capacities

Remote organ impairments are frequent and increase patient morbidity and mortality after lower limb ischemia-reperfusion (IR). We challenged the hypothesis that lower limb IR might also impair lung, renal, and liver mitochondrial respiration. Two-hour tourniquet-induced ischemia was performed on both hindlimbs, followed by a two-hour reperfusion period in C57BL6 mice. Lungs, liver and kidneys maximal mitochondrial respiration (V(max)), complexes II, III, and IV activity (V(succ)), and complex IV activity (V(TMPD)) were analyzed on isolated mitochondria. Lower limb IR decreased significantly lung V(max) (29.4 ± 3.3 versus 24 ± 3.7 μmol O2/min/g dry weight, resp.; P = 0.042) and tended to reduce V(succ) and V(TMPD). IR did not modify liver but increased kidneys mitochondrial respiration (79.5 ± 19.9 versus 108.6 ± 21.4, P = 0.035, and 126 ± 13.4 versus 142.4 ± 10.4 μmol O2/min/g dry weight for V(max) and V(succ), resp.). Kidneys mitochondrial coupling was increased after IR (6.5 ± 1.3 versus 8.8 ± 1.1, P = 0.008). There were no histological changes in liver and kidneys. Thus, lung mitochondrial dysfunction appears as a new early marker of hindlimb IR injuries in mice. Further studies will be useful to determine whether enhanced kidneys mitochondrial function allows postponing kidney impairment in lower limb IR setting.

Carotid revascularization: risks and benefits

Despite a decline during the recent decades in stroke-related death, the incidence of stroke has remained unchanged or slightly increased, and extracranial carotid artery stenosis is implicated in 20%–30% of all strokes. Medical therapy and risk factor modification are first-line therapies for all patients with carotid occlusive disease. Evidence for the treatment of patients with symptomatic carotid stenosis greater than 70% with either carotid artery stenting (CAS) or carotid endarterectomy (CEA) is compelling, and several trials have demonstrated a benefit to carotid revascularization in the symptomatic patient population. Asymptomatic carotid stenosis is more controversial, with the largest trials only demonstrating a 1% per year risk stroke reduction with CEA. Although there are sufficient data to advocate for aggressive medical therapy as the primary mode of treatment for asymptomatic carotid stenosis, there are also data to suggest that certain patient populations will benefit from a stroke risk reduction with carotid revascularization. In the United States, consensus and practice guidelines dictate that CEA is reasonable in patients with high-grade asymptomatic stenosis, a reasonable life expectancy, and perioperative risk of less than 3%. Regarding CAS versus CEA, the best-available evidence demonstrates no difference between the two procedures in early perioperative stroke, myocardial infarction, or death, and no difference in 4-year ipsilateral stroke risk. However, because of the higher perioperative risks of stroke in patients undergoing CAS, particularly in symptomatic, female, or elderly patients, it is difficult to recommend CAS over CEA except in populations with prohibitive cardiac risk, previous carotid surgery, or prior neck radiation. Current treatment paradigms are based on identifying the magnitude of perioperative risk in patient subsets and on using predictive factors to stratify patients with high-risk asymptomatic stenosis.

What do providers, payers and patients need from comparative effectiveness research on diagnostics? The case of HER2/Neu testing in breast cancer

AIMS

Comparing effectiveness of diagnostic tests is one of the highest priorities for comparative effectiveness research (CER) set by the Institute of Medicine. Our study aims to identify what information providers, payers and patients need from CER on diagnostics, and what challenges they encounter implementing comparative information on diagnostic alternatives in practice and policy.

MATERIALS & METHODS

Using qualitative research methods and the example of two alternative protocols for HER2 testing in breast cancer, we conducted interviews with 45 stakeholders: providers (n = 25) from four academic and eight nonacademic institutions, executives (n = 13) from five major US private payers and representatives (n = 7) from two breast cancer patient advocacies.

RESULTS

The need for additional scientific evidence to determine the preferred HER2 protocol was more common for advocates than payers (100 vs 54%; p = 0.0515) and significantly more common for advocates than providers (100 vs 40%; p = 0.0077). The availability of information allowing assessment of the implementation impact from alternative diagnostic protocols on provider institutions may mitigate the need for additional scientific evidence for some providers and payers (24 and 46%, respectively). The cost-effectiveness of alternative protocols from the societal perspective is important to payers and advocates (69 and 71%, respectively) but not to providers (0%; p = 0.0001 and p = 0.0001). The lack of reporting laboratory practices is a more common implementation challenge for payers and advocates (77 and 86%, respectively) than for providers (32%). The absence of any mechanism for patient involvement was recognized as a challenge by payers and advocates (69 and 100%, respectively) but not by providers (0%; p = 0.0001 and p = 0.0001).

CONCLUSION

Comparative implementation research is needed to inform the stakeholders considering diagnostic alternatives. Transparency of laboratory practices is an important factor in enabling implementation of CER on diagnostics in practice and policy. The incongruent views of providers versus patient advocates and payers on involving patients in diagnostic decisions is a concerning challenge to utilizing the results of CER.