Appendix 2.

ICD-9 Codes Used for Secondary Hospitalization Analysis

ICD-9 CodeDescription
460Acute nasopharyngitis
461Acute sinusitis
462Acute pharyngitis
463Acute tonsillitis
464Acute laryngitis and tracheitis
465Acute upper respiratory infections of multiple or unspecified sites
466Acute bronchitis and bronchiolitis
470Deviated nasal septum
471Nasal polyps
472Chronic pharyngitis and nasopharyngitis
473Chronic sinusitis
474Chronic disease of tonsils and adenoids
475Peritonsillar abscess
476Chronic laryngitis and laryngotracheitis
477Allergic rhinitis
478Other diseases of upper respiratory tract
480Viral pneumonia
481Pneumococcal pneumonia
482Other bacterial pneumonia
483Pneumonia due to other specified organism
484Pneumonia in infectious diseases classified elsewhere
485Bronchopneumonia, organism unspecified
486Pneumonia, organism unspecified
487Influenza
490Bronchitis, not specified elsewhere
491Chronic bronchitis
492Emphysema
493Asthma
494Bronchiectasis
495Extrinsic allergic alveolitis
496Chronic airway obstruction, not elsewhere classified
510Empyema
511Pleurisy
512Pneumothorax
513Abscess of lung and mediastinum
514Pulmonary congestion and hypostasis
515Postinflammatory pulmonary fibrosis
516Other alveolar and parietoalveolar pneumonopathy
517Lung involvement in conditions classified elsewhere
518Other diseases of lung
519Other diseases of respiratory system