SADT in COPD and Oscillometry in Obstructive Airway Disease in Primary Care. The SCOOP-study (SCOOP)

Rationale: The Small Airways are a major site of obstruction in many respiratory diseases, including COPD. More insight into a diagnosis of Small Airways Dysfunction (SAD) in patients with COPD is clinically valuable as it might enable tailored pharmacotherapy. Currently, methods to diagnose SAD in COPD are not standardized and are not available in routine clinical practice. The Small Airways Dysfunction Tool (SADT) was developed to identify patients with asthma and SAD. Initially, the SADT included a comprehensive 63-item questionnaire. The number of items has been reduced to a SADT-asthma (SADT a) questionnaire and key patient and disease characteristics for it to be feasible and implementable in clinical practice. Although there are many similarities between asthma and COPD, there might be differences in clinical characteristics and responses to small airways dysfunction between the two diseases. The current study aims to adapt the original 63-item SADT questionnaire for dedicated use in COPD by reducing the number of items, and identifying COPD-SAD-specific items, to enhance its efficiency in identifying SAD when combined with key patient and disease characteristics in individuals with COPD (SADT-c). In addition, a comparison of diagnostic accuracy of spirometry and oscillometry will be made by interpretations by a panel of experts to provide a triage diagnosis. The previously developed machine learning AC/DC tool will be used to explore its diagnostic accuracy using oscillometry and spirometry results. This can contribute to standardizing oscillometry in clinical practice.

Study Overview

• Status: Active, not recruiting
• Conditions: Asthma; COPD; Small Airway Disease
• Intervention / Treatment: Diagnostic test: Oscillometer ALDS

• Study Type: Observational
• Enrollment (Actual): 108

Contacts and Locations

Study Locations

• Netherlands
  • Groningen, Netherlands
    • Primary care sites across the Netherlands

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

The study population for the SCOOP study will consist of patients referred by their General Practitioner (GP) to the Asthma/COPD service. Patients can be referred by their GP when they are suspected to have asthma, Chronic Obstructive Pulmonary Disease (COPD), asthma-COPD overlap (ACO) or when they present with pulmonary symptoms of unknown origin. After referral by the GP, patients will be invited by the Asthma/COPD service. Both patients invited for an initial diagnostic visit or a control visit can participate in the SCOOP study.

Description

Inclusion Criteria:

• Suspected of having COPD, asthma or ACO as indicated by the referring GP OR a previous diagnosis of COPD

Exclusion Criteria:

• Inability to understand and sign the written informed consent form.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Participants with Small Airway Disease	Diagnostic test: Oscillometer ALDS; Oscillometry is a non-invasive technique for assessing lung function, as it requires only 45-60 seconds of tidal breathing to measure the mechanical properties of the respiratory system. This makes the measurement suitable for patients of all ages and with severe respiratory conditions. It also reduces the number of errors as compared to other methods (e.g., spirometry). Oscillometry can be used to evaluate airway resistance, reactance, and compliance, insights that are challenging to obtain with other methods. This quality makes oscillometry especially sensitive for obstructive diseases like asthma and COPD, and correlations with physiological small airways dysfunction have also been shown . The Ambulatory Lung Diagnosis System (ALDS), manufactured by Lothar MedTec, can be used to perform oscillometry and spirometry. The ALDS follows the European Respiratory Society (ERS) technical standards for measurement and reporting of oscillometry.
Participants without Small Airway Disease	Diagnostic test: Oscillometer ALDS; Oscillometry is a non-invasive technique for assessing lung function, as it requires only 45-60 seconds of tidal breathing to measure the mechanical properties of the respiratory system. This makes the measurement suitable for patients of all ages and with severe respiratory conditions. It also reduces the number of errors as compared to other methods (e.g., spirometry). Oscillometry can be used to evaluate airway resistance, reactance, and compliance, insights that are challenging to obtain with other methods. This quality makes oscillometry especially sensitive for obstructive diseases like asthma and COPD, and correlations with physiological small airways dysfunction have also been shown . The Ambulatory Lung Diagnosis System (ALDS), manufactured by Lothar MedTec, can be used to perform oscillometry and spirometry. The ALDS follows the European Respiratory Society (ERS) technical standards for measurement and reporting of oscillometry.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The predictive value of SADT-c for detecting SAD in patients with COPD.	To determine whether SADT-c can be used in patients with COPD to detect SAD.	At baseline study visit, during pulmonary function testing

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Predictive value of SADT-a bronze model for SAD in COPD.	To determine whether the bronze model SADT-a is predictive for SAD in COPD.	At baseline study visit, during pulmonary function testing
Develop SADT-c.	Agreement between SADT-c results and disease parameters.	At baseline study visit, using data collected during pulmonary function testing and clinical assessment
To evaluate how SADT-c compares to SADT-a.	Relative predictive value of SADT-a versus SADT-c for SAD in COPD defined as R5-R20 > ULN1	At baseline study visit, during pulmonary function testing
To determine whether oscillometry and spirometry are equally effective for triage diagnosis in patients in primary care with respiratory symptoms.	Agreement between triage diagnoses from oscillometry and spirometry. Relative usability of spirometry and oscillometry.	At baseline study visit, during initial diagnostic assessment in primary care
Assess the diagnostic performance of the Asthma/COPD Differentiation Classification (AC/DC) Tool.	Diagnostic performance of AC/DC tool compared to expert panel diagnosis.	At baseline study visit, with expert panel diagnosis based on data collected during the study assessment

Collaborators and Investigators

• Sponsor: General Practitioners Research Institute

Study record dates

Study Major Dates

• Study Start (Actual): May 1, 2024
• Primary Completion (Actual): August 1, 2025
• Study Completion (Estimated): June 1, 2026

Study Registration Dates

• First Submitted: January 15, 2026
• First Submitted That Met QC Criteria: January 23, 2026
• First Posted (Actual): January 28, 2026

Study Record Updates

• Last Update Posted (Actual): January 28, 2026
• Last Update Submitted That Met QC Criteria: January 23, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Oscillometry; SADT-c
• Additional Relevant MeSH Terms: Pathologic Processes; Chronic Disease; Disease Attributes; Immune System Diseases; Respiratory Tract Diseases; Lung Diseases; Bronchial Diseases; Lung Diseases, Obstructive; Respiratory Hypersensitivity; Hypersensitivity, Immediate; Hypersensitivity; Pathological Conditions, Signs and Symptoms; Pulmonary Disease, Chronic Obstructive; Asthma
• Other Study ID Numbers: GPRI-2024-002

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No