Evidence map›Paper›PMID 35176872›Full record

ArticleCirculation. Cardiovascular interventions2022

Ankle- and Toe-Brachial Index for Peripheral Artery Disease Identification: Unlocking Clinical Data Through Novel Methods.

Julia E Friberg, Abdul H Qazi, Brenden Boyle, Carrie Franciscus, Mary Vaughan-Sarrazin, Dax Westerman, Olga V Patterson, Sharidan K Parr, Michael E Matheny, Shipra Arya and 4 more

Open access · bronzeAbstract read
In one paragraph

Article in Circulation. Cardiovascular interventions, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 10 papers.

0numbers the graph read from it
0cells of the map it votes in
10citing papers in PubMed
1.7field-weighted citation impact, top 17% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

10 citing papers in PubMed, 8 citations in OpenAlex.

  1. Article
  2. Article
  3. Review
  4. Article
  5. Blood Pressure and Risk of Clinical Events in Peripheral Artery Disease.medRxiv : the preprint server for health sciences · 2025
    Article
  6. Article
  7. Article
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

14 authors at 8 institutions in 1 country.

Julia E Friberg *Center for Access and Delivery Research and Evaluation, Iowa City Veterans Affairs Medical Center (J.E.F., C.F., M.V.-S., B.C.L., S.G.), Department of Medicine, University of Iowa Carver College of Medicine, Iowa City.
Abdul H Qazi *Division of Cardiovascular Diseases, Massachusetts General Hospital, Boston (A.H.Q.).
Brenden BoyleDivision of Cardiovascular Medicine, University of Minnesota, Minneapolis (B.B.).ORCID 0000-0002-4403-2691
Carrie FranciscusCenter for Access and Delivery Research and Evaluation, Iowa City Veterans Affairs Medical Center (J.E.F., C.F., M.V.-S., B.C.L., S.G.), Department of Medicine, University of Iowa Carver College of Medicine, Iowa City.
Mary Vaughan-SarrazinCenter for Access and Delivery Research and Evaluation, Iowa City Veterans Affairs Medical Center (J.E.F., C.F., M.V.-S., B.C.L., S.G.), Department of Medicine, University of Iowa Carver College of Medicine, Iowa City.ORCID 0000-0001-8717-1061
Dax WestermanDepartment of Biomedical Informatics (M.E.M, G.T.G, D.W.), Vanderbilt University Medical Center, Nashville, TN.ORCID 0000-0002-9547-7789
Olga V PattersonSalt Lake City Veterans Affairs Medical Center, UT (O.V.P.).ORCID 0000-0002-8717-5975
Sharidan K ParrDepartment of Medicine (M.E.M, S.K.P), Vanderbilt University Medical Center, Nashville, TN.ORCID 0000-0002-4596-3818
Michael E MathenyTennessee Valley Healthcare System, Nashville (M.E.M., G.T.G.).ORCID 0000-0003-3217-4147
Shipra AryaDepartment of Surgery, Palo Alto Veterans Affairs Medical Center and Stanford University, CA (S.A.).ORCID 0000-0002-0404-9325
Kim G SmolderenDepartment of Medicine and Psychiatry, Yale University School of Medicine, New Haven, CT (K.G.S.).ORCID 0000-0001-6104-6254
Brian C LundCenter for Access and Delivery Research and Evaluation, Iowa City Veterans Affairs Medical Center (J.E.F., C.F., M.V.-S., B.C.L., S.G.), Department of Medicine, University of Iowa Carver College of Medicine, Iowa City.ORCID 0000-0001-5191-728X
Glenn T Gobbel *Tennessee Valley Healthcare System, Nashville (M.E.M., G.T.G.).ORCID 0000-0002-5368-7737
Saket Girotra *Center for Access and Delivery Research and Evaluation, Iowa City Veterans Affairs Medical Center (J.E.F., C.F., M.V.-S., B.C.L., S.G.), Department of Medicine, University of Iowa Carver College of Medicine, Iowa City.ORCID 0000-0002-4784-4513
Iowa City VA Health Care System · USUniversity of Iowa · USVanderbilt University Medical Center · USVA Tennessee Valley Healthcare System · USVeterans Health Administration · USMassachusetts General Hospital · USUniversity of Minnesota · USYale University · US

Funding

Peripheral Artery Disease: Long-term Survival & Outcomes Study (PEARLS)R01HL166305 · NHLBI · UT SOUTHWESTERN MEDICAL CENTER · PI Saket Girotra · 2023 to 2026
$2.5M
Peripheral Artery Disease: Long-term Survival & Outcomes Study (PEARLS)R56HL158803 · NHLBI · UT SOUTHWESTERN MEDICAL CENTER · PI GIROTRA, SAKET · 2021 to 2021
$633k
HSRD VA I21 HX002365NHLBI NIH HHS R01 HL166305NHLBI NIH HHS R56 HL158803
6 · The paper itself

Abstract

backgroundDespite its high prevalence and clinical impact, research on peripheral artery disease (PAD) remains limited due to poor accuracy of billing codes. Ankle-brachial index (ABI) and toe-brachial index can be used to identify PAD patients with high accuracy within electronic health records.

methodsWe developed a novel natural language processing (NLP) algorithm for extracting ABI and toe-brachial index values and laterality (right or left) from ABI reports. A random sample of 800 reports from 94 Veterans Affairs facilities during 2015 to 2017 was selected and annotated by clinical experts. We trained the NLP system using random forest models and optimized it through sequential iterations of 10-fold cross-validation and error analysis on 600 test reports and evaluated its final performance on a separate set of 200 reports. We also assessed the accuracy of NLP-extracted ABI and toe-brachial index values for identifying patients with PAD in a separate cohort undergoing ABI testing.

resultsThe NLP system had an overall precision (positive predictive value) of 0.85, recall (sensitivity) of 0.93, and F1 measure (accuracy) of 0.89 to correctly identify ABI/toe-brachial index values and laterality. Among 261 patients with ABI testing (49% PAD), the NLP system achieved a positive predictive value of 92.3%, sensitivity of 83.1%, and specificity of 93.1% to identify PAD when compared with a structured chart review. The above findings were consistent in a range of sensitivity analysis.

conclusionsWe successfully developed and validated an NLP system for identifying patients with PAD within the Veterans Affairs electronic health record. Our findings have broad implications for PAD research and quality improvement.

Indexed as

Ankle Brachial IndexPeripheral Arterial DiseaseAnkleHumansLower ExtremityPredictive Value of TestsTreatment Outcomeankle-brachial indexhumansnatural language processingperipheral artery diseaseprevalence

Identifiers

PMID35176872
PMCPMC10807980
OpenAlexW4212794574

What OpenQuestion holds

Textmetadata
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Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.