Send to:

Choose Destination
See comment in PubMed Commons below
Br J Sports Med. 2011 Mar;45(3):203-8. doi: 10.1136/bjsm.2009.068395. Epub 2010 May 19.

Reliability and validity testing of a single-item physical activity measure.

Author information

  • 1British Heart Foundation National Centre for Physical Activity and Health, School of Sport, Exercise and Health Sciences, Loughborough University, Leicestershire LE11 3TU, UK.



To develop and test a new single-item physical activity screening tool, suitable for assessing respondents' eligibility for behaviour change interventions.


Two single-item assessment tools were developed, one using a "past week" recall period, the other using a "past month" recall period. A quota sampling system was used to recruit 480 adults from across England, Scotland and Wales. Half the sample completed the past-week question and half completed the past-month version. Test-retest reliability was assessed over a 2- to 5-day period. Concurrent validity was assessed using the Global Physical Activity Questionnaire and the UK Active People Survey. All surveys were completed via telephone interviews.


Both versions of the single-item instrument demonstrated strong reproducibility (r=0.72-0.82), using Spearman's rank correlation coefficients. The past-week recall question showed strong agreement in the classification of respondents meeting the current physical activity recommendation (kappa=0.63, 95% CI 0.54 to 0.72).Concurrent validity over the past week compared to the Global Physical Activity Questionnaire was modest (r=0.53) and slightly weaker for the past month compared to the Active People Survey (r=0.33-0.48).


Both versions of the new single-item measure performed as well as other short physical activity tools in terms of reliability and concurrent validity. Criterion validity testing of the single-item measure is recommended to establish its ability to assess objectively measured physical activity levels. In addition, further research to assess the responsiveness of the single-item measure in detecting changes in physical activity will inform its usefulness in programme evaluation.

[PubMed - indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Write to the Help Desk