When performing a presumptive blood test control sample on a bloody shirt where should the control sample be taken?

Question

Quizplus · Accepted Answer

The control sample should be taken proximal to the stain, but in an unstained area as it allows for a comparison between the color and intensity of the control reagent and the known sample. This ensures that any reaction observed in the stain is due to the presence of blood and not to some other interfering substance. Taking the control sample in a different blood stain or another area within the same blood stain may not provide an accurate comparison. Taking the control sample as far away from the stained area may not be feasible or practical.

When Performing a Presumptive Blood Test Control Sample on a Bloody