title: Precision and accuracy of self-measured peak expiratory flow rates in chronic obstructive pulmonary disease.
abstract: BACKGROUND
  The precision and accuracy of self-measured peak expiratory flow rates (PEFR) have not been determined for patients with chronic obstructive pulmonary disease (COPD).
  
  
  METHODS
  Twenty-eight male veterans recorded their PEFR twice daily, before and after bronchodilators, for 6 months. Spirometry was also done in the pulmonary function laboratory up to 11 times per patient during the observation period. A 4-week "baseline" was identified for each patient. Baseline coefficients of variation (CV) were calculated for the morning (AM) and evening (PM) PEFR, before (PRE) and after (POST) bronchodilators.
  
  
  RESULTS
  The baseline CVs for AMPRE, AMPOST, PMPRE and PMPOST were 14.9+/-6.9%, 12.6+/-5.6%, 14.9+/-4.8%, and 11.2+/-6.0%, respectively. There were strong correlations between self-measured PEFR and values obtained in the pulmonary function laboratory on the same day.
  
  
  CONCLUSIONS
  Self-measured PFFRs are reasonably precise and accurate in patients with COPD.
authors.affiliation: Veterans Affairs Medical Center, and the Department of Medicine, University of New Mexico School of Medicine, Albuquerque 87108, USA.
authors.forename: G H
authors.initials: GH
authors.lastname: Murata
authors.forename: D J
authors.initials: DJ
authors.lastname: Lium
authors.forename: H K
authors.initials: HK
authors.lastname: Busby
authors.forename: C O
authors.initials: CO
authors.lastname: Kapsner
mesh_terms: D000368:Aged; D004311:Double-Blind Method; D006801:Humans; D008173:Lung Diseases, Obstructive / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D010366:Peak Expiratory Flow Rate; D011446:Prospective Studies; D013147:Spirometry