Variables
The patient variables (Table 1) were processed both from the structured
and coded EHR data (visits, procedure codes and diagnoses of the
patients) and free clinical texts (diagnoses and comorbidities, Figure
S2, Table S1). Comorbidity-related variables were obtained from ICD-10
codes (Table S3) and by using validated keyword-based information
extraction from free clinical texts (Please see further methods in this
article’s supporting information). For asthma we used ICD-10 codes J45.,
which is doctor-diagnosed lung-function test -confirmed asthma. NERD
diagnosis was obtained from EHR text and was based on typical history of
airway symptoms after ingestion of NSAID ± challenge test confirmation
of NERD.