Methotrexate (MTX) polyglutamate (MTXPG
Patients with RA treated with MTX were enrolled. Specimens were collected by fingerstick (volumetric absorptive microsampler) and venipuncture to measure MTXPG
Intraday and interday precision ranged from 2.0% to 10.9% and 3.1% to 10.8%, respectively, at MTXPG
Capillary blood MTXPG