Treating chronic knee pain with acupuncture--reply.

burned. Underlying differences in device accuracy may be compounded in these measures. Our study is limited by being conducted with young, healthy volunteers in a controlled setting with a convenience sample of a small number of applications and devices. Results should be confirmed in other settings and with other devices. Increased physical activity facilitated by these devices could lead to clinical benefits not realized by low adoption of pedometers. Our findings may help reinforce individuals’ trust in using smartphone applications and wearable devices to track health behaviors, which could have important implications for strategies to improve population health.