followup vs scrutiny

followup and scrutiny both are nouns.

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

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

followup: 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 followup include examination.

followup (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)
an activity that continues something that has already begun or that repeats something that has already been done	a prolonged intense look
a piece of work that exploits or builds on earlier work