Accuracy and Usability of a Self-Administered 6-Minute Walk Test Smartphone Application

Circ Heart Fail. 2015 Sep;8(5):905-13. doi: 10.1161/CIRCHEARTFAILURE.115.002062. Epub 2015 Aug 17.


Background: The 6-minute walk test (6MWT) independently predicts congestive heart failure severity, death, and heart failure hospitalizations, but must be administered in clinic by qualified staff on a premeasured course. As part of the Health eHeart Study, we sought to develop and validate a self-administered 6MWT mobile application (SA-6MWTapp) for independent use at home by patients.

Methods and results: We performed a validation study of an SA-6MWTapp in 103 participants. In phase 1 (n=52), we developed a distance-estimation algorithm for the SA-6MWTapp by comparing step counts from an Actigraph and measured distance on a premeasured 6MWT course with step counts and estimated distance obtained simultaneously from our SA-6MWTapp (best estimation algorithm, r=0.89 [95% confidence interval 0.78-0.99]). In phase 2, 32 participants (including those with congestive heart failure and pulmonary hypertension) used the SA-6MWTapp independently in clinic, and the distance estimated by the SA-6MWTapp was compared with the measured distance (r=0.83 [95% confidence interval 0.79-0.92]). In phase 3, 19 patients with congestive heart failure and pulmonary hypertension consecutively enrolled from clinic performed 3.2±1 SA-6MWTapp tests per week at home over 2 weeks. Distances estimated from the SA-6MWTapp during home 6MWTs were highly repeatable (coefficient of variation =4.6%) and correlated with in-clinic-measured distance (r=0.88 [95% confidence interval 0.87-0.89]). Usability surveys performed during the second (in-clinic) and third (at-home) phases demonstrated that the SA-6MWTapp was simple and easy to use independently.

Conclusions: An SA-6MWTapp is easy to use and yields accurate repeatable measurements in the clinic and at home.

Keywords: disease management; exercise test; heart failure; hypertension; mobile applications; pulmonary; smartphone; telemedicine.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Validation Study
  • Video-Audio Media

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Algorithms
  • Exercise Test / methods*
  • Exercise Tolerance / physiology*
  • Female
  • Follow-Up Studies
  • Heart Failure / diagnosis*
  • Heart Failure / physiopathology
  • Humans
  • Male
  • Middle Aged
  • Reproducibility of Results
  • Smartphone / statistics & numerical data*
  • Time Factors
  • Walking / physiology*
  • Young Adult