Evidence map›Paper›PMID 41109898›Full record

ArticleAnnals of biomedical engineering2026

Developing an Empirical Acoustic Transfer Function Model for the Upper Airway.

Walid Ashraf, Ali Alqudah, Matthew Band, Lingyu Zhao, Brian Lithgow, Ahmed Elwali, Zahra Moussavi

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Article in Annals of biomedical engineering, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
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

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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

1 citing paper in PubMed.

  1. Article
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

7 authors.

Walid AshrafBiomedical Engineering Program, University of Manitoba, Winnipeg, Manitoba, Canada. Walid.ashraf@umanitoba.ca.ORCID http://orcid.org/0000-0003-1593-6285
Ali AlqudahBiomedical Engineering Program, University of Manitoba, Winnipeg, Manitoba, Canada.
Matthew BandDepartment of Electrical and Computer Engineering, McGill University, Montreal, Quebec, Canada.
Lingyu ZhaoDivision of Engineering Science, University of Toronto, Toronto, Ontario, Canada.
Brian LithgowBiomedical Engineering Program, University of Manitoba, Winnipeg, Manitoba, Canada.
Ahmed ElwaliBiomedical Engineering Program, Marian University, Indianapolis, Indiana, USA.
Zahra MoussaviBiomedical Engineering Program, University of Manitoba, Winnipeg, Manitoba, Canada.

Funding

Mitacs IT39986Research Manitoba 5792
6 · The paper itself

Abstract

purposeIn this pilot study, we introduce a novel approach for the upper airway acoustic modelling aimed at developing a patient-specific transfer function of the upper airway. We modelled the upper airway as an acoustic filter, and hypothesized the parameters of such model would correlate with the anatomical features.

methodsThe method involved generating a signal with known frequency characteristics at the mouth while recording the output at the suprasternal notch. Five distinct protocols were tested, and a consistency study was conducted to identify the most suitable protocol. The protocols varied in terms of input sound type and breathing maneuvers. Ten healthy subjects participated in this pilot study over three days with four recordings per day.

resultsThe results indicated that the most consistent protocol utilizing white noise as the input sound while the participant breathed passively. The standard error of the difference between the detected peak frequencies was less than 10%, and the standard error for the amplitude difference was less than 5 dB. Additionally, the transfer function for each participant was modelled as a cascade of six 2nd order systems. A strong negative correlation of - 0.91 (p = 0.0003) was found between the first natural frequency and the participants' height, while a positive correlation of 0.69 (p = 0.027) was observed between the transfer function gain and the participants' BMI.

conclusionThis study presents an initial step toward developing an acoustic transfer function of the upper airway, which could ultimately be used to classify and diagnose respiratory disorders.

Indexed as

Models, BiologicalAcousticsAdultFemaleHumansMalePilot ProjectsAcoustic transfer functionRespiratory diagnosticsRespiratory disorder diagnosisSystem identificationUpper airway modelling

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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.