Jarabawar ɗaukar iodine radioactive (RAIU) hanya ce ta likitanci da ake amfani da ita don kimanta aikin thyroid. A cikin wannan gwajin, ana ba wa majiyyaci ɗan ƙaramin iodine na rediyoaktif ta baki, sannan a auna adadin iodin na rediyoaktif ɗin da glandar thyroid ya ɗauka na tsawon lokaci, yawanci sa'o'i 24. Ana amfani da wannan gwajin don sanin yadda glandar thyroid ke aiki da kuma gano duk wani rashin lafiya ko cututtuka irin su hyperthyroidism, hypothyroidism, ko ciwon daji na thyroid. Sakamakon gwajin RAIU zai iya taimaka wa likitoci don yin cikakken ganewar asali da kuma tsara maganin da ya dace.