Reliability of the 6-minute walking test smartphone application

Area of Science:

• Biomedical Engineering
• Rehabilitation Medicine
• Digital Health

Background:

• The 6-minute walking test (6WT) is crucial for assessing functional capacity in degenerative lumbar spine diseases.
• Traditional 6WT requires specialized facilities and personnel, limiting its accessibility.
• There is a need for convenient, patient-centered functional assessment tools.

Purpose of the Study:

• To develop and validate a smartphone application for measuring 6-minute walking distance (6WD).
• To compare the accuracy and reliability of the app-based 6WD with the gold-standard distance wheel (DW).
• To assess the feasibility of the app for at-home patient monitoring.

Main Methods:

• A free iOS/Android app was developed using GPS for 6WD measurement in home environments.
• 6WD measurements were collected across various smartphone models, settings, and walking patterns.
• Relative measurement error (|rME| < 7.5%) and intraclass correlation coefficient (ICC) were used to determine reliability.

Main Results:

• The app demonstrated high reliability (ICC = 0.97) in neighborhood, nature, and open city environments with varied walking patterns.
• Measurements were unreliable indoors, in dense urban areas, and on rectangular courses.
• Slower walking speeds increased measurement error, but mathematical adjustments improved accuracy (ICC = 0.98).

Conclusions:

• The developed smartphone app provides a reliable and convenient method for measuring 6WD using GPS.
• This tool empowers patients to independently monitor their functional status, particularly post-treatment for lumbar spine conditions.
• The app offers a promising, accessible alternative to traditional 6WT in real-world settings.