1. Office of Medical Student Research, Oklahoma State University Center for Health Sciences, Tulsa, Oklahoma, USA
2. Department of Psychiatry and Behavioral Sciences, Oklahoma State University Center for Health Sciences, Tulsa, Oklahoma, USA
3. Department of Statistics, Oklahoma State University, Stillwater, Oklahoma, USA
4. Samuel J. Wood Library & C. V. Starr Biomedical Information Center, Weill Cornell Medical College, New York, New York, USA