The invention provides methods for automated classification of a medical diagnostic image of a lung according to its deduced probability of relating to a lung of a patient who is suffering from a diffuse parenchymal lung disease such as chronic obstructive pulmonary disease (COPD), cystic fibrosis, or severe asthma, or to a class of patients characterized by the severity of such a condition, or to a class of patients characterized by a prognostic likelihood of developing such a condition or severity of condition.