A study of the sensitivity and specificity of four presumptive tests for blood.

The purpose of this work was to conduct a comparative study of the sensitivity and specificity of phenolphthalein, tetramethylbenzidine, leucomalachite green, and orthotolidine as presumptive tests for blood. The findings of this study indicate that the phenolphthalein and the leucomalachite green tests are the most specific and that the tetramethylbenzidine and orthotolidine tests are the most sensitive of the group. The author concludes that the phenolphthalein test is the best single test for evaluating suspected bloodstains.