Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Grades and scores on final examination. A. Grades on the final exam subdivided by non-users (white bars), moderate users (grey bars) and intensive users (black bars). B. Score on bonus questions in the final exam. C. Corrected examination scores (total score minus bonus question score). Data are presented as means ± SEM. *p < 0.05 compared to non-users, #p < 0.05 compared to moderate users.
