Assess Accuracy of Primary Care Asthma and COPD Diagnosis Using Oscillometry and FeNO vs Specialist Diagnosis

Current diagnostic methods for asthma and chronic obstructive pulmonary disease mostly depend on pulmonary function tests, especially spirometry. While spirometry is a foundational tool, its diagnostic accuracy is often limited by the patient's ability to perform forceful breathing maneuvers, as well as technical and reproducibility challenges, and the need for proper equipment and training. These constraints can compromise effective diagnosis of asthma and COPD in primary care settings. Prompt and accurate diagnosis by primary care physicians is essential for better patient outcomes. Although variable airflow limitation often measured as a change in FEV1 after bronchodilator is a hallmark of asthma, inconsistencies in test quality and reversibility criteria create challenges in distinguishing asthma from COPD. These complexities highlight the need for alternative diagnostic tools beyond traditional spirometry. This observational study is designed to evaluate the diagnostic accuracy and technical feasibility of using oscillometry and FeNO testing in primary care for suspected asthma and COPD, compared to conventional specialist-based diagnostics. The study will be conducted across 6 countries in the MEA, Asia, and Latin America, with two hospital sites per country. Primary care physicians will be trained in oscillometry and FeNO testing using standardized protocols and tools such as the Ambulatory Lung Diagnosis System following GINA and GOLD guidelines. Eligible patients will provide consent, complete a history and symptom questionnaire, and undergo primary care-based assessment for a provisional diagnosis. If specialist assessment cannot occur the same day, it will be done within three days. No follow-up visits are planned. Study outcomes will inform the feasibility and accuracy of integrating these methods into routine care, aiming to improve the early and reliable diagnosis of asthma and COPD.