Cited by 229Clinical practice guidelines implementationHealth Sciences Research and EducationMeta-analysis and systematic reviews

Levels of Evidence Supporting American College of Cardiology/American Heart Association and European Society of Cardiology Guidelines, 2008-2018

Open access
Fanaroff, Alexander C., Califf, Robert M., Windecker, Stephan, Smith, Sidney C., Lopes, Renato D.·2019·JAMA

Abstract

Importance: Clinical decisions are ideally based on evidence generated from multiple randomized controlled trials (RCTs) evaluating clinical outcomes, but historically, few clinical guideline recommendations have been based entirely on this type of evidence. Objective: To determine the class and level of evidence (LOE) supporting current major cardiovascular society guideline recommendations, and changes in LOE over time. Data Sources: Current American College of Cardiology/American Heart Association (ACC/AHA) and European Society of Cardiology (ESC) clinical guideline documents (2008-2018), as identified on cardiovascular society websites, and immediate predecessors to these guideline documents (1999-2014), as referenced in current guideline documents. Study Selection: Comprehensive guideline documents including recommendations organized by class and LOE. Data Extraction and Synthesis: The number of recommendations and the distribution of LOE (A [supported by data from multiple RCTs or a single, large RCT], B [supported by data from observational studies or a single RCT], and C [supported by expert opinion only]) were determined for each guideline document. Main Outcomes and Measures: The proportion of guideline recommendations supported by evidence from multiple RCTs (LOE A). Results: Across 26 current ACC/AHA guidelines (2930 recommendations; median, 121 recommendations per guideline [25th-75th percentiles, 76-155]), 248 recommendations (8.5%) were classified as LOE A, 1465 (50.0%) as LOE B, and 1217 (41.5%) as LOE C. The median proportion of LOE A recommendations was 7.9% (25th-75th percentiles, 0.9%-15.2%). Across 25 current ESC guideline documents (3399 recommendations; median, 130 recommendations per guideline [25th-75th percentiles, 111-154]), 484 recommendations (14.2%) were classified as LOE A, 1053 (31.0%) as LOE B, and 1862 (54.8%) as LOE C. When comparing current guidelines with prior versions, the proportion of recommendations that were LOE A did not increase in either ACC/AHA (median, 9.0% [current] vs 11.7% [prior]) or ESC guidelines (median, 15.1% [current] vs 17.6% [prior]). Conclusions and Relevance: Among recommendations in major cardiovascular society guidelines, only a small percentage were supported by evidence from multiple RCTs or a single, large RCT. This pattern does not appear to have meaningfully improved from 2008 to 2018.

Integrity signals

Registry

Crossref · 10.1001/jama.2019.1122

Cites

167 of 167 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 11 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    Among class I and III recommendations in current ESC guidelines, 49.6% were LOE C.

    “934 (49.6%) as LOE C”
    Quote in the paperNot a substantial claim
  • Findingown data

    Among class I recommendations in current ESC guidelines, 21.5% were LOE A.

    “Of 1622 class I recommendations, 349 (21.5%) were LOE A.”
    Quote in the paperNot a substantial claim
  • Findingown data

    Among class I and III recommendations in current ESC guidelines, 21.3% were LOE A.

    “ESC guidelines contained 1884 class I and class III recommendations, 402 (21.3%) classified as LOE A”
    Quote in the paperNot a substantial claim
  • Findingown data

    In 26 current ACC/AHA guidelines (2930 recommendations), 8.5% of recommendations were classified as LOE A.

    “Across 26 current ACC/AHA guidelines (2930 recommendations; median, 121 recommendations per guideline [25th-75th percentiles, 76-155]), 248 recommendations (8.5%) were classified as LOE A”
    • Also stated in: § Results · plain
      “Across the 26 current ACC/AHA guidelines, 248 recommendations (8.5%) were classified as LOE A”
    • Also stated in: § Discussion · plain
      “less than 10% of recommendations from current ACC/AHA guidelines”
    Quote in the paperSubstantial claim
  • Findingown data

    In 26 current ACC/AHA guidelines, 41.5% of recommendations were LOE C.

    “1217 (41.5%) as LOE C”
    • Also stated in: § Results · plain
      “1217 (41.5%) as LOE C”
    Quote in the paperSubstantial claim
  • May combine two claims. 8
  • Classified as probably not a substantial claim. 13
  • May combine two claims.

    Findingown data

    Among ESC guidelines with prior versions, the median proportion of LOE A recommendations was 15.1% in current vs 17.6% in prior, indicating no increase.

    “or ESC guidelines (median, 15.1% [current] vs 17.6% [prior])”
    • Also stated in: § ESC Guidelines · plain
      “the median proportion of LOE A recommendations was 15.1% (25th-75th percentiles, 3.7%-26.4%);the median proportion of LOE A recommendations among prior guidelines was 17.6% (25th-75th percentiles, 2.4%-27.6%)”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data

    Among ACC/AHA guidelines with prior versions, the median proportion of LOE A recommendations was 9.0% in current vs 11.7% in prior, indicating no increase.

    “the proportion of recommendations that were LOE A did not increase in either ACC/AHA (median, 9.0% [current] vs 11.7% [prior])”
    • Also stated in: § Changes From Prior to Current Guidelines ACC/AHA Guidelines · plain
      “the median proportion of LOE A recommendations was 9.0% (25th-75th percentiles, 4.8%-15.1%);the median proportion of LOE A recommendations in prior guidelines was 11.7% (25th-75th percentiles, 5.8%-17.5%)”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data

    There was wide variety by subject area; some guideline documents had >33% LOE A, others had none.

    “there was wide variety by subject area-in some guideline documents, more than 33% of recommendations were characterized as LOE A, but others had no LOE A recommendations at all.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Some steps to improve clinical trial efficiency and funding have been taken in the intervening years.

    “In the intervening years, some of these steps have been taken, [6][7][8]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [6][7][8]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data

    Recommendations were abstracted by a single reviewer and validated by another reviewer.

    “recommendations were abstracted by a single reviewer (A.C.F.) and validated by another reviewer (R.D.L).”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductreasoning

    Abstraction involved simple reporting and did not require judgment.

    “Abstraction therefore involved simple reporting of the content of each document and did not require judgment on the part of the abstractors.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    Exclusion of focused updates may lead to underestimation of the proportion of LOE A recommendations.

    “exclusion of focused updates, which are usually undertaken when new RCT evidence is generated, may lead to underestimation of the proportion of LOE A recommenda-tions”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Study design and conductnone given

    Standards for LOE A designation may have changed over time.

    “Alternatively, standards for LOE A designation may have changed over time.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S2 (checkable), S4 (based).

    Study design and conductnone given

    This limitation should not affect findings regarding changes in LOE over time.

    “however, this limitation should not affect findings regarding changes in LOE over time.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim.

    Study design and conductnone given

    The evidence supporting major society guideline recommendations is a surrogate for the totality of evidence in cardiology, not a direct measurement.

    “First, the evidence supporting major society guideline recommendations is a surrogate for the totality of the evidence in cardiology, rather than a direct measurement.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    The increase in LOE B recommendations could indicate that the proportion supported by randomized evidence is increasing.

    “this increase in LOE B recommendations could indicate that the proportion of recommendations supported by randomized evidence is increasing”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    In 2009, Tricoci et al found that 12% of ACC/AHA guideline recommendations were LOE A, including 19% of class I recommendations.

    “At that time, 12% of guideline recommendations were classified as LOE A, including 19% of class I recommendations.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [5] source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    In 6 guideline documents, Tricoci et al found minimal increases in LOE A recommendations compared with LOE B and C.

    “in these 6 guideline documents, they found minimal increases in LOE A recommendations compared with LOE B and C.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [5] source

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    Variability among subspecialties compounded the lack of RCT evidence; some subspecialty guidelines contained almost no LOE A recommendations.

    “The lack of RCT evidence supporting most recommendations in the guidelines was compounded by variability among subspecialties within cardiovascular medicine; some subspecialty guidelines contained almost no LOE A recommendations.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    This review describes only evidence supporting cardiology guidelines, not across medical and surgical subspecialties.

    “Third, this review describes only evidence supporting cardiology guidelines, rather than across medical and surgical subspecialties”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim.

    Study design and conductnone given

    The quality of evidence supporting each recommendation was not independently assessed.

    “The quality of evidence supporting each recommendation was not independently assessed”
    Quote in the paperSubstantial claim
  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Solid RCT evidence delineates treatments and strategies that lead to better patient outcomes, which can then be implemented in clinical practice.

    “Solid RCT evidence delineates treatments and strategies that lead to better patient outcomes, which can then be implemented in clinical practice.106”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [106] source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

    Interpretationreasoning

    The high global prevalence of cardiovascular disease suggests that efforts to build a higher-quality cardiovascular medicine evidence base might have a large effect on global health.

    “the high global prevalence of cardiovascular disease suggests that efforts to build a higher-quality cardiovascular medicine evidence base might have a large effect on global health.”
    Quote in the paperNot a substantial claim
18 of 18
  • The paper relies on this without support.

    The ACC/AHA and ESC guidelines are the major cardiovascular society guidelines.

    “major cardiovascular society guideline recommendations”
  • The paper relies on this without support.

    The LOE categories are comparable across ACC/AHA and ESC guidelines.

    “Although the ESC and ACC/AHA guidelines use similar evidence to generate recommendations”
  • The paper relies on this without support.

    The included guideline documents are representative of the evidence base for cardiovascular medicine.

    “Only comprehensive guideline documents were included in this systematic review”
  • The paper relies on this without support.

    The websites used to identify guidelines listed all current guidelines as of February 1, 2019.

    “Current ACC/AHA guidelines were identified as those posted on the ACC (https://www.acc.org/guidelines#doctype= Guidelines) and ESC (https://www.escardio.org/Guidelines/ Clinical-Practice-Guidelines) websites as of February 1, 2019.”
  • The paper relies on this without support.

    The prior guideline documents identified are the immediate predecessors covering the same topic.

    “Current guidelines were also reviewed to identify references to a previous iteration of the same guideline”
5 of 5

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • The same earlier review is assigned two LOE A percentages

    Minor

    The introduction attributes an 11% LOE A figure to the 2009 ACC/AHA guideline review, while the discussion attributes 12% to that same cited review.

1 of 1

Cites

Flagged first, then by citations

1 of the 168 references couldn’t be matched to a known paper.

Cited by

Sorted by citations

Authors
Fanaroff, A. C., Califf, R. M., Windecker, S., Smith, S. C., & Lopes, R. D.
Affiliations
  • Duke University (US)
  • University of Bern (CH)
  • University of North Carolina at Chapel Hill (US)
  • Division of Cardiology and Duke Clinical Research Institute, Duke University, Durham, North Carolina
Venue
JAMA
Published
2019-03-19
Volume
321
Issue
11
Pages
1069
ISSN
  • 0002-9955 (ISSN-L)
  • 0098-7484
OpenAlex
W2921176698
Cited by
228
References
168
Citations by year
2026: 17 · 2025: 30 · 2024: 30 · 2023: 28 · 2022: 32 · 2021: 30 · 2020: 39 · 2019: 22
FWCI
5.03
Type
journal article
Language
en
Open access
Locations
  • JAMA (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Bern Open Repository and Information System (University of Bern) (submittedVersion)
Funders
  • American Heart Association (17FTF33661087)
  • Amgen
  • Bristol-Myers Squibb
  • Eli Lilly and Company
  • Pfizer
  • GlaxoSmithKline
  • Sanofi
  • Biogen
  • Edwards Lifesciences
  • Boston Scientific Corporation
  • Cytokinetics
  • Genentech
Topics
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Clinical practice guidelines implementation
  • Health Sciences › Health Professions › General Health Professions › Health Sciences Research and Education
  • Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Meta-analysis and systematic reviews
Keywords
level of evidence, cardiovascular guidelines, ACC/AHA guidelines, ESC guidelines, randomized controlled trials, guideline recommendations, expert opinion, guideline revision, cardiovascular care
MeSH terms
American Heart Association, Cardiology, Cardiovascular Diseases, Europe, Societies, Medical, United States, Randomized Controlled Trials as Topic, Practice Guidelines as Topic, Evidence-Based Medicine, Observational Studies as Topic

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-07.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-07.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review