results

Results and discusion: It was shown, initially, that the general knowledge about vaccination were (was) scarce and (there were) misunderstandings (by/of) legal guardians of students. After intervention, expanded knowledge (was) imparted through the educational sessions. Several studies demonstrate that educational interventions have benefits as the knowledge of those involved in these (them) are (is) increased.

Very good. You have used complicated English grammar here. Be careful to identify the subject of your sentence as singular or plural - it can be difficult to do this when you use compound sentences and prepositional phrases (many native speakers make this mistake often, especially in speech).