title: Diagnosis is difficult.
authors.forename: Gerhard W
authors.initials: GW
authors.lastname: Sybrecht
mesh_terms: D003937:Diagnosis, Differential; D003951:Diagnostic Errors / Q000517:prevention & control*; D042241:Early Diagnosis; D006801:Humans; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis*; D012129:Respiratory Function Tests / Q000379:methods*