1. Auckland Bioengineering Institute, University of Auckland , 1010 Auckland, New Zealand
2. Department of Biomedical Informatics and Medical Education, University of Washington , Seattle, WA 98195, United States
3. eScience Institute, University of Washington , Seattle, WA 98195, United States
4. Paul G. Allen School of Computer Science, University of Washington , Seattle, WA 98195, United States
5. Department of Bioengineering, University of Washington , Seattle, WA 98195, United States