Research Study Abstract

Comparison of Subjective and Objective Measures of Sedentary Behavior Using the Yale Physical Activity Survey and Accelerometry in Patients with Rheumatoid Arthritis

  • Published on Apr 2016

Background: Sedentary behavior is associated with increased risk of functional decline and disability. Individuals with rheumatoid arthritis (RA) spend more time sedentary than healthy adults. Self-reported assessment of sedentary behavior has not been well-developed in this patient population.

Methods: 172 adults with RA wore an accelerometer for 7 days and completed a modified version of the Yale Physical Activity Survey (YPAS). YPAS-derived sedentary estimates included 1) daily sitting categories (<3, 3 to 6, 6 to 8, >8 hours/day), 2) continuous daily sedentary time calculated by subtracting hours spent sleeping or in physical activity from a 24-hour day, and 3) rank order of YPAS-derived continuous daily sedentary time. Each estimate was compared with objective accelerometer-derived sedentary time using linear regression and Bland-Altman analysis.

Results: A significant relationship was observed between accelerometer-derived sedentary time and all 3 estimates. Bland-Altman plot demonstrated systematic bias, however Bland-Altman plot of rank-order demonstrated that the ranked YPAS-derived continuous estimate was an unbiased predictor of ranked accelerometer sedentary time though limits of agreement were wide.

Conclusions: This patient-reported approach using the YPAS shows promise to be a useful tool to identify the most sedentary patients. Providing a practical and accurate tool may increase the frequency sedentary behavior is assessed by clinicians.


  • Abigail L. Gilbert 1
  • Jungwha Lee 2
  • Madelein Ma 2
  • Pamela A. Semanik 3
  • Loretta DiPietro 4
  • Dorothy D. Dunlop 5
  • Rowland W. Chang 2


  • 1

    Division of Rheumatology

  • 2

    Dept of Preventive Medicine

  • 3

    Dept of Physical Medicine and Rehabilitation; Northwestern University Feinberg School of Medicine, Chicago, IL

  • 4

    Dept of Exercise Science, George Washington University School of Public Health and Health Services, Washington, DC

  • 5

    Center for Healthcare Studies, Northwestern University, Chicago, IL


Journal of Physical Activity and Health