This field was greatly advanced in a landmark 2000 Lasne and de Ceaurriz study, and an important concept in this field is determination of (*) specific gravity of a certain substance.  
Historical procedures used in this field include ones named after Frommer and Legal.  In this field, sulfosalicylic acid is used in the Kingsbury-Clark procedure, while other procedures use Esbach's reagent and Trinder reagent.  This field was greatly advanced in a landmark 2000 Lasne and de Ceaurriz study, and an important concept in this field is determination of (*) specific gravity of a certain substance.  One popular method uses the so-called "dipstick," and among the commercial applications of this field are home pregnancy tests. For 10 points, name this field that uses non-invasive collection methods to diagnose metabolic disorders or detect drug use, which people have tried to undermine using maskers and the Whizzinator.
Historical procedures used in this field include ones named after Frommer and Legal.  
{urine test}ing [accept {urinalysis}; grudgingly prompt on early {drug test}ing] (2) [DW]