Shear-wave splitting measurements are widely used to analyze orien- tations of anisotropy. We compare two different shear-wave splitting techniques, which are generally assumed to give similar results. Using a synthetic test, which covers the whole backazimuthal range, we find characteristic differences, however, in fast-axis and delay-time estimates near Null directions between the rotation cor- relation and the minimum energy method. We show how this difference can be used to identify Null measurements and to determine the quality of the result. This tech- nique is then applied to teleseismic events recorded at station LVZ in northern Scan- dinavia, for which our method constrains the fast-axis azimuth to be 15� and the delay time 1.1 sec. Online material: Additional comparisons between the RC and SC techniques.