t distribution curve with 30 degrees of freedom demonstrating one and two areas of rejection. t distribution curve with 30 degrees of freedom demonstrating one and two areas of rejection. A t statistic to be −1.43 lies in an area of acceptance of the null hypothesis using the two tailed test [t(crit) = −2.042] or rejection using the one tailed test [t(crit) = −1.31]. P Driscoll, and F Lecky Emerg Med J 2001;18:214-221 Copyright © BMJ Publishing Group Ltd and the College of Emergency Medicine. All rights reserved.