Compensation for graduate research assistants on NIH awards is tied to the zero level postdoctoral stipend established for the National Research Service Award program. The March 7th NIH Guide contains a Notice announcing increases in the stipend levels for NRSA awardees, effective for awards made with fiscal year 2003 funds - that is, awarded on or after October 1, 2002. The Notice is at http://grants.nih.gov/grants/guide/notice-files/NOT-OD-03-033.html