title: Facilitating Secure Sharing of Personal Health Data in the Cloud.
abstract: BACKGROUND
  Internet-based applications are providing new ways of promoting health and reducing the cost of care. Although data can be kept encrypted in servers, the user does not have the ability to decide whom the data are shared with. Technically this is linked to the problem of who owns the data encryption keys required to decrypt the data. Currently, cloud service providers, rather than users, have full rights to the key. In practical terms this makes the users lose full control over their data. Trust and uptake of these applications can be increased by allowing patients to feel in control of their data, generally stored in cloud-based services.
  
  
  OBJECTIVE
  This paper addresses this security challenge by providing the user a way of controlling encryption keys independently of the cloud service provider. We provide a secure and usable system that enables a patient to share health information with doctors and specialists.
  
  
  METHODS
  We contribute a secure protocol for patients to share their data with doctors and others on the cloud while keeping complete ownership. We developed a simple, stereotypical health application and carried out security tests, performance tests, and usability tests with both students and doctors (N=15).
  
  
  RESULTS
  We developed the health application as an app for Android mobile phones. We carried out the usability tests on potential participants and medical professionals. Of 20 participants, 14 (70%) either agreed or strongly agreed that they felt safer using our system. Using mixed methods, we show that participants agreed that privacy and security of health data are important and that our system addresses these issues.
  
  
  CONCLUSIONS
  We presented a security protocol that enables patients to securely share their eHealth data with doctors and nurses and developed a secure and usable system that enables patients to share mental health information with doctors.
authors.affiliation: Software Engineering Lab, School of Electrical and Information Engineering, The University of Sydney, Sydney, Australia. Danan.Thilakanathan@sydney.edu.au.
authors.forename: Danan
authors.identifier: http://orcid.org/0000-0002-2463-8477
authors.initials: D
authors.lastname: Thilakanathan
authors.forename: Rafael A
authors.initials: RA
authors.lastname: Calvo
authors.forename: Shiping
authors.identifier: http://orcid.org/0000-0002-4603-0024
authors.initials: S
authors.lastname: Chen
authors.forename: Surya
authors.identifier: http://orcid.org/0000-0002-3289-6599
authors.initials: S
authors.lastname: Nepal
authors.forename: Nick
authors.identifier: http://orcid.org/0000-0002-0476-9146
authors.initials: N
authors.lastname: Glozier
keywords: computer security; information dissemination; privacy; self care; telemedicine