reexamination vs scrutiny

reexamination and scrutiny both are nouns.

Word	Noun	Adjective	Verb	Adverb
reexamination	Yes	No	No	No
scrutiny	Yes	No	No	No

As nouns, scrutiny is a hypernym of reexamination; that is, scrutiny is a word with a broader meaning than reexamination:

reexamination: a subsequent examination of a patient for the purpose of monitoring earlier treatment
scrutiny: the act of examining something closely (as for mistakes)

Other hypernyms of reexamination include examination.

reexamination (noun)	scrutiny (noun)
a subsequent examination of a patient for the purpose of monitoring earlier treatment	the act of examining something closely (as for mistakes)
(law) questioning of a witness by the party that called the witness after that witness has been subject to cross-examination	a prolonged intense look