Final answer:
Partial thromboplastin time (PTT) is used for heparin therapy to monitor the therapeutic level of heparin.
Step-by-step explanation:
Evaluating partial thromboplastin time (PTT) is used for heparin therapy. Partial thromboplastin time (PTT) is a blood test that measures the time it takes for a clot to form. It is used to monitor heparin therapy and ensure that the therapeutic level is achieved. The therapeutic level for PTT in heparin therapy is typically 1.5 to 2 times the control value.