title: A single question reliably identifies physically inactive women in primary care.
abstract: OBJECTIVE
  To validate a single-item screening question for systematic use in primary health care to identify physically inactive adults, who may benefit from physical activity intervention.
  
  
  METHODS
  The single-item physical activity screening question was administered to 1171 women aged 51-74 years recruited from 10 general practices, followed by a longer validated physical activity questionnaire (the NZPAQ-LF). Sensitivity, specificity, likelihood ratios, positive and negative predictive values, and a Kappa statistic were calculated to assess validity of the screening question.
  
  
  RESULTS
  The sensitivity of the single-item question was 76.7% (95% confidence interval [CI] 73.5-79.7). It had high specificity (81.1%, 95%CI 77.2-84.4), and a high positive predictive value (86.7%, 95%CI 83.8-89.1). The positive likelihood ratio was 4.05 (3.33-4.93), and negative likelihood ratio was 0.29 (0.25-0.33). The Kappa statistic calculated for the single-item screening question when validated against the NZPAQ-LF was 0.56 (p<0.001).
  
  
  CONCLUSIONS
  The single-item screening question has good sensitivity, specificity, and concordance with a validated physical activity questionnaire. The question is easy to administer and elicits a simple yes/no response from patients. This validated tool can now be used in practice to identify women who would benefit from physical activity interventions in primary care.
authors.affiliation: Department of Primary Health Care and General Practice, Wellington School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand. Sally.Rose@otago.ac.nz
authors.forename: Sally B
authors.initials: SB
authors.lastname: Rose
authors.forename: C Raina
authors.initials: CR
authors.lastname: Elley
authors.forename: Beverley A
authors.initials: BA
authors.lastname: Lawton
authors.forename: Anthony C
authors.initials: AC
authors.lastname: Dowell
mesh_terms: D000368:Aged; D002318:Cardiovascular Diseases / Q000503:physiopathology*; D003920:Diabetes Mellitus / Q000503:physiopathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D009765:Obesity / Q000503:physiopathology*; D011237:Predictive Value of Tests; D011320:Primary Health Care / Q000379:methods*; D012189:Retrospective Studies; D011795:Surveys and Questionnaires