OBJECTIVES: The aim of this investigation was to examine the impact of (1) different criteria for definition of GOLD groups, and (2) use of information from different German data sources on GOLD classification of a COPD patient.

METHODS: In this non-interventional data linkage study, primary data (PD) of COPD patients provided by treating physicians were linked to claims data (CD) of a German sickness fund (AOK Nordost). PD included all information relevant for GOLD classification (exacerbations, airflow (FEV), COPD assessment test (CAT) and modified Medical Research Council (mMRC) scale). Additionally, exacerbation frequency was obtained from CD. Based on all available data, four different methods were simulated for assessment of GOLD groups (guideline update 2014): (1) CAT+FEV/exacerbations (PD); (2) CAT+FEV/exacerbations (CD); (3) mMRC+FEV/exacerbations (PD); (4) mMRC+FEV/exacerbations (CD).

RESULTS: CONCLUSIONS: GOLD classification can vary as a result of the used data sources (PD/CD) and especially, according to the method used to assess symptoms (CAT/mMRC). This may have a substantial impact on COPD patients’ treatment as GOLD treatment recommendations vary across different GOLD groups.