protocolSection identificationModule nctId: NCT06383130, orgStudyIdInfo id: 24SM8792, briefTitle: London Asthma Diagnostics Study, acronym: LADS, statusModule overallStatus: NOT_YET_RECRUITING, startDateStruct date: 2024-06, primaryCompletionDateStruct date: 2025-12, completionDateStruct date: 2026-07, studyFirstPostDateStruct date: 2024-04-25, lastUpdatePostDateStruct date: 2024-04-25, sponsorCollaboratorsModule leadSponsor name: Imperial College London, class: OTHER, collaborators name: Asthma UK, collaborators name: General Practitioners Research Institute, descriptionModule briefSummary: The goal of this trial is to learn if the addition of oscillometry with reversibility testing increases diagnostic accuracy in adult asthma diagnosis, when added to current standard of care tests: spirometry with reversibility testing and Fractional Exhaled Nitric Oxide (FeNO). The main question it aims to answer is:- Does oscillometry with reversibility testing increase diagnostic accuracy in detection of asthma in adults when added to spirometry with reversibility and FeNO?Researchers will evaluate the diagnostic accuracy of this approach with the reference standard, which is a clinically adjudicated diagnosis of asthma by two respiratory clinicians based on history and investigation results.Participants will* Undergo oscillometry testing alongside their routine asthma investigations within their scheduled clinic visit* Optionally participate in our sub-studies on new breath and nasal swab tests for asthma* Optionally participate in our qualitative substudy on patients views and attitudes to asthma testing and oscillometry, conditionsModule conditions: Asthma, designModule studyType: OBSERVATIONAL, designInfo observationalModel: OTHER, timePerspective: PROSPECTIVE, enrollmentInfo count: 225, type: ESTIMATED, armsInterventionsModule interventions name: Oscillometry with reversibility testing, interventions name: Breath volatile testing, interventions name: Nasal eosinophil peroxidase, interventions name: Handheld capnometry, outcomesModule primaryOutcomes measure: To evaluate the diagnostic accuracy (sensitivity, specificity) of a combination of oscillometry ± reversibility, spirometry ± reversibility and FeNO, secondaryOutcomes measure: To conduct an analysis comparing the diagnostic accuracy of (i) oscillometry ± reversibility with spirometry ± reversibility, (ii) spirometry±reversibility with FeNO and (iii) oscillometry ±reversibility and FeNO, secondaryOutcomes measure: To compare the concordance of positive and negative test results for (i) oscillometry±reversibility, (ii) spirometry ±reversibility and (iii) Fractional Exhaled Nitric Oxide (FeNO), secondaryOutcomes measure: To collect data on (i) testing time, (ii) testing burden, (iii) general feasibility of implementation of the asthma diagnostic tests, otherOutcomes measure: To evaluate the diagnostic accuracy of the targeted reactive aldehyde species (RASP) panel in breath for asthma diagnosis, otherOutcomes measure: To evaluate the diagnostic accuracy of nasal biomarker eosinophil peroxidase (EPX), otherOutcomes measure: To evaluate the diagnostic accuracy of tidal breath CO2 waveforms using the N-Tidal handheld capnometry device, eligibilityModule sex: ALL, minimumAge: 18 Years, stdAges: ADULT, stdAges: OLDER_ADULT, contactsLocationsModule locations facility: Imperial College Healthcare NHS Trust, city: London, zip: W2 1PG, country: United Kingdom, geoPoint lat: 51.50853, lon: -0.12574, locations facility: Imperial College Healthcare NHS Trust, city: London, zip: W21NY, country: United Kingdom, contacts name: Eleanor Quek, MBBS, role: CONTACT, phone: 07411429994, email: e.quek@imperial.ac.uk, contacts name: Salman Siddiqui, PhD, role: CONTACT, email: s.siddiqui@imperial.ac.uk, contacts name: Salman Siddiqui, PhD, role: PRINCIPAL_INVESTIGATOR, geoPoint lat: 51.50853, lon: -0.12574, locations facility: Nottingham University Hospitals NHS Trust, city: Nottingham, zip: NG7 2UH, country: United Kingdom, contacts name: Matthew Martin, PhD, role: CONTACT, email: matthew.martin4@nottingham.ac.uk, contacts name: Matthew Martin, PhD, role: SUB_INVESTIGATOR, geoPoint lat: 52.9536, lon: -1.15047, hasResults: False