What do you suggest if my drug screen was 15.7 on a 20 point scale but on a previous lab it was 0.6 mg/dl where would it be on a 20 point scale?

Dont understand ?: I am not aware of any kind of "scale" used to describe drug amounts. Drugs are measured generally in nanograms per milliliter of urine or blood (ng/ml). There are 1000 ng in one milligram, and 100 ml in one deciliter (dl) which is not a common way to express any drug concentration except alcohol, which is commonly given in milligrams per deciliter. Give more info on what drug you are using.