title: Comparison of pedometer and activity diary for measurement of physical activity in chronic obstructive pulmonary disease.
abstract: OBJECTIVE
  Precise, inexpensive tools for measuring physical activity levels are important for developing strategies to improve symptoms and enhance quality of life in chronic obstructive pulmonary disease (COPD). Self-report questionnaires and diaries have been used in many populations with variable results. The pedometer is widely recognized as a valid and reliable objective measurement tool, but it has not been well tested in COPD. This study aimed to determine the relationship between free-living physical activity recorded in a daily diary and that measured by using a pedometer in patients with COPD.
  
  
  METHODS
  Participants with COPD (n = 80) recorded physical activity over 7 days. Cumulative pedometer readings and diary records of 4 activity categories for each 0.5 hour were compared.
  
  
  RESULTS
  Participants (n = 76) with complete data sets were included in the analysis. The diary was more reliably completed. Mean pedometer reading per week was 23,129 (SD = 17,083) "step" counts (range, 1,725-66,454). Mean diary-recorded standing and walking time per week was 98.9 (SD = 10.4) hours (range, 73-119.5). The relationship between these measures was moderate and statistically significant (r = 0.37, P = .001).
  
  
  CONCLUSIONS
  A daily diary record appears to offer more promise than the pedometer as a tool for measuring free-living physical activity in patients with COPD. Further research is required to assess the value of the 2 methods as discriminative, evaluative, and predictive tools in COPD populations.
authors.affiliation: The Northern Clinical Research Centre, Northern Hospital, Epping, Australia.
authors.forename: Rosemary
authors.initials: R
authors.lastname: Moore
authors.forename: David
authors.initials: D
authors.lastname: Berlowitz
authors.forename: Linda
authors.initials: L
authors.lastname: Denehy
authors.forename: Bruce
authors.initials: B
authors.lastname: Jackson
authors.forename: Christine F
authors.initials: CF
authors.lastname: McDonald
mesh_terms: D000368:Aged; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D009043:Motor Activity; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000534:rehabilitation*; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D014797:Vital Capacity; D016138:Walking