Table 2Initial list of evidence gaps

PICO ElementEvidence Gaps
Population
  1. What is the comparative safety and effectiveness of treatment in subgroups of special importance, such as individuals with essential hypertension and at least one of the following: ischemic heart disease, diabetes mellitus, congestive heart failure, chronic kidney disease, and dyslipidemia?
  2. What is the comparative safety and effectiveness of specific subgroups such as the elderly and ethnic and racial minorities?
Interventions and comparators
3.

Are there differential effects of specific ACEIs, ARBs, or DRIs that are not shared by other agents within their respective medication class?

Outcomes
4.

What is the comparative effectiveness of these medications on cardiovascular and cerebrovascular events measured over several years?

5.

What is the comparative effectiveness of these medications on cancer-related outcomes, which are infrequently reported in the existing literature?

6.

What are the incidence, timing, and clinical consequences of angioedema in patients treated with ACEIs, ARBs, or DRIs?

Implementation gaps
7.

Are there important differences in medication adherence and persistence with drug therapy across the different classes of drug?.

8.

What are the provider patterns of prescribing these medications, and what interventions are used to support evidence-based decisionmaking about prescribing?

Methods for evidence synthesis
9.

What are the best methods for synthesis of data across clinical conditions (e.g. congestive heart failure, ischemic heart disease, and chronic kidney disease) to better understand the comparative effectiveness of ACEIs, ARBs, and DRIs?

Abbreviations: ACEI(s) = angiotensin-converting enzyme inhibitor(s); ARB(s) = angiotensin II receptor blocker(s)/antagonist(s); DRI(s) = direct renin inhibitor(s); PICO = population, interventions, comparators, and outcomes

From: Methods

Cover of Future Research Needs for Angiotensin-Converting Enzyme Inhibitors (ACEIs), Angiotensin II Receptor Antagonists (ARBs), or Direct Renin Inhibitors (DRIs) for Treating Hypertension
Future Research Needs for Angiotensin-Converting Enzyme Inhibitors (ACEIs), Angiotensin II Receptor Antagonists (ARBs), or Direct Renin Inhibitors (DRIs) for Treating Hypertension: Identification of Future Research Needs From Comparative Effectiveness Review No. 34 [Internet].
Future Research Needs Papers, No. 14.
Powers BJ, Crowley MJ, McCrory DC, et al.

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