Relationship between early life asthma and chronic airway disease in adult life – In search for disease trajectories over the life span - The RELATE study based on the Kongsberg cohort

This paper describes the design and methodology of a study designed to evaluate the relationship between severe childhood asthma and obstructive lung disease in adulthood. The study will be based on the Kongsberg cohort, comprising ~5000 children with severe asthma who underwent a 4-month stay at an asthma care facility in Kongsberg, Norway between 1950 and 1979. Members of the cohort still alive will be invited to a follow-up examination to assess their current health status, including lung function testing (FEV1, FVC, FEV1/FVC ratio), which will be measured using the Vitalograph Pneumotrac spirometer.