A Novel Smartphone Application for "Smart" Trials

Test-retest Reliability and Validity of and a Novel Smartphone Application to Objectively Measure Physical Function in Healthy Individuals

The overarching goal is to develop a mHealth App that can use smartphone embedded sensors to objectively collect physical function data in healthy individuals in the context of daily life.

The goal is to develop a mHealth App using smartphone embedded sensors to objectively collect physical function data in healthy individuals in the context of daily life. The investigators will perform technical development of an internet-interactive App to collect, analyze and transfer the subjects' data. As a proof-of-concept, the mHealth App will execute algorithms that automate deployment of three well-established physical function tests. In a laboratory setting, it will be evaluated usability, acceptability and reliability of the mHealth App compared with traditional performance tests among focus groups. The investigators will then evaluate its usability and acceptability when used in the participants' home environments.

Inclusion Criteria:

• Male or female subjects at least 50 years old with symptomatic knee osteoarthritis
• English Speaker
• Be able to walk 20 meters without an assistive device, such as a cane, walker or crutches.
• Have an iPhone 6 or higher with internet connection.

Exclusion Criteria:

• Prior surgery on either knee within 6 months of enrollment
• Received corticosteroid injection in the knee within 3 months of enrollment
• Evidence or history of knee disease or trauma