Smart-phone based monitoring of cancer related fatigue

Cancer related fatigue is a chronic disease that may persist up to 10 years after treatment of cancer has been finished successfully and is one of the most prevalent problems of cancer survivors. Cancer related fatigue is a complex symptom that is not sufficiently understood and difficult to remedy. Patients do not necessarily follow a treatment plan with regular in-office follow-ups. As a consequence, physicians lack of knowledge how their patients are coping with their fatigue in daily life. To overcome the resulting knowledge gap, we developed a smart-phone based monitoring system providing activity data from smart-phone sensors. Furthermore, based on self-reports following the experience based sampling method, the app asks the patients to report their perceived degree of fatigue and interference of fatigue with daily life by means of digital questionnaires. To evaluate the monitoring system in an observational study, we recruited 7 patients suffering from cancer related fatigue and tracked them over 2 to 3 weeks. We collected about 2700 hours of activity data and over 500 completed questionnaires. Based on this study, we conclude that our monitoring system can be used in a clinical trial to examine cancer related fatigue.