Evaluating the Feasibility and Reliability of Using Handheld Nebulizers to Conduct Cough Sensitivity Testing With Citric Acid

NCT07531901 | Not Yet Recruiting

• 2 other identifiers: IRB-FY2026-312P20GM130418-06
• Study Type: interventional
• Target: 10
• Locations: 0 countries
• Sites: N/A

Brief Summary

Objective cough reflex sensitivity testing is typically restricted to specialized research laboratories due to reliance on expensive dosimeter-controlled aerosol delivery systems. This study evaluates the feasibility and reliability of a low-cost alternative method using a handheld nebulizer for citric acid cough challenge testing. Healthy adult participants will complete cough reflex sensitivity testing using both a standard dosimeter-controlled nebulizer system (Cosmed QuarkSpiro) and a handheld nebulizer (DeVilbiss 45). The study will compare cough threshold outcomes between methods to determine whether handheld nebulizer-based testing produces comparable and reproducible measurements.

Conditions

Cough Reflex Sensitivity

Keywords

cough challenge testing; cough reflex sensitivity testing

Outcome Measures

Primary Outcomes (2)

• Test-retest reliability of the concentration of citric acid that elicits two or more coughs (C2)

  The test-retest reliability (Intraclass correlation coefficient) of the citric acid concentration required to elicit two coughs during cough challenge testing will be evaluated and compared for each testing method.

  Cough sensitivity testing to determine cough thresholds (C2) will be performed at each of four weekly study visits, with visits occurring every 7 days across a 4-week study period.

• Test-retest reliability of the concentration of citric acid that elicits five or more coughs (C5)

  The test-retest reliability (Intraclass correlation coefficient) of the citric acid concentration required to elicit five coughs during cough challenge testing will be evaluated and compared for each testing method.

  Cough sensitivity testing to determine cough thresholds (C5) will be performed at each of four weekly study visits, with visits occurring every 7 days across a 4-week study period.

Study Arms (2)

Dosimeter-Controlled Cough Reflex Sensitivity Testing

ACTIVE COMPARATOR

Participants will undergo cough reflex sensitivity testing using a dosimeter-controlled nebulizer system (Cosmed QuarkSpiro) to deliver aerosolized citric acid.

Device: Cosmed QuarkSpiro Dosimeter-Controlled Nebulizer

Handheld Nebulizer Cough Reflex Sensitivity Testing

EXPERIMENTAL

Participants will undergo cough reflex sensitivity testing using a handheld nebulizer (DeVilbiss 45) to deliver aerosolized citric acid.

Device: DeVilbiss 45 Handheld Nebulizer

Interventions

DeVilbiss 45 Handheld Nebulizer DEVICE

Commercial handheld nebulizer used to deliver aerosolized citric acid during cough challenge testing.

Handheld Nebulizer Cough Reflex Sensitivity Testing

Cosmed QuarkSpiro Dosimeter-Controlled Nebulizer DEVICE

Laboratory spirometry system equipped with a dosimeter-controlled nebulizer used to deliver standardized aerosolized citric acid during cough challenge testing.

Dosimeter-Controlled Cough Reflex Sensitivity Testing

Eligibility Criteria

• Age: 18 Years - 89 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Healthy adults at least 18 years of age
• Consent to audio/video recording of the research sessions for research purposes
• Spirometry testing results obtained by study team on same day of first testing session with FEV1/FVC ratio and FEV1 percent predicted values of at least 0.70

You may not qualify if:

• Pregnant or trying to become pregnant (if capable of becoming pregnant- a urine pregnancy test will be provided onsite and a negative result must be obtained prior to the first testing session)
• Smoking of any substance in the last six months
• Diagnosed or suspected pulmonary disease (e.g., asthma, COPD)
• History of chronic cough
• History of head or neck cancer
• History of neurological disease (e.g., cerebrovascular accident)
• History of dysphagia (swallowing difficulty)
• Current complaint of a voice problem
• Current upper respiratory infection

Sponsors & Collaborators

• University of Montana: lead
• National Institute of General Medical Sciences (NIGMS): collaborator

Central Study Contacts

Jane E Salois, PhD

CONTACT

406-243-2138; jane.salois@umontana.edu

Laurie J Slovarp, PhD

CONTACT

406-243-2107; laurie.slovarp@umontana.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Healthy adult participants will complete cough sensitivity testing using two aerosol delivery systems.

Study Record Dates

• First Submitted: March 17, 2026
• First Posted: April 15, 2026
• Study Start (Estimated): May 16, 2026
• Primary Completion (Estimated): February 1, 2027
• Study Completion (Estimated): February 28, 2027
• Last Updated: April 21, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF
• Time Frame: IPD and supporting information will be available as soon as one month after data are published and available for up to three years after publication.
• Access Criteria: Data will be shared with qualified investigators who provide a methodologically sound proposal and documentation of appropriate institutional approvals, where required. Data will be shared in a de-identified format consistent with institutional policies and applicable privacy protections. Due to the small sample size, additional safeguards may be implemented to prevent potential participant re-identification.