Derivation and validation of a composite index of severity in chronic obstructive pulmonary disease: the DOSE Index

Am J Respir Crit Care Med. 2009 Dec 15;180(12):1189-95. doi: 10.1164/rccm.200902-0271OC. Epub 2009 Sep 24.


Rationale: Chronic obstructive pulmonary disease (COPD) is increasingly recognized as a multicomponent disease with systemic consequences and effects on quality of life. Single measures such as lung function provide a limited reflection of how the disease affects patients. Composite measures have the potential to account for many of the facets of COPD.

Objectives: To derive and validate a multicomponent assessment tool of COPD severity that is applicable to all patients and health care settings.

Methods: The index was derived using data from 375 patients with COPD in primary care. Regression analysis led to a model explaining 48% of the variance in health status as measured by the Clinical COPD Questionnaire with four components: dyspnea (D), airflow obstruction (O), smoking status (S), and exacerbation frequency (E). The DOSE Index was validated in cross-sectional and longitudinal samples in various health care settings in Holland, Japan, and the United Kingdom.

Measurements and main results: The DOSE Index correlated with health status in all data sets. A high DOSE Index score (> or = 4) was associated with a greater risk of hospital admission (odds ratio, 8.3 [4.1-17]) or respiratory failure (odds ratio, 7.8 [3.4-18.3]). The index predicted exacerbations in the subsequent year (P < or = 0.014).

Conclusions: The DOSE Index is a simple, valid tool for assessing the severity of COPD. The index is related to a range of clinically important outcomes such as health care consumption and predicts future events.

Publication types

  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Aged
  • Cohort Studies
  • Cross-Sectional Studies
  • Dyspnea / etiology
  • Female
  • Health Status
  • Hospitalization / statistics & numerical data
  • Humans
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Odds Ratio
  • Pulmonary Disease, Chronic Obstructive / complications
  • Pulmonary Disease, Chronic Obstructive / diagnosis*
  • Reproducibility of Results
  • Respiratory Insufficiency / etiology
  • Severity of Illness Index
  • Smoking / adverse effects
  • Surveys and Questionnaires