Rilevanza vs. pertinenza
The Italian words rilevanza and pertinenza both translate to the English word relevance, but they describe different concepts. The word rilevanza refers to the importance, weight, or significance of something, whereas pertinenza refers to how closely something is connected, applicable, or on-topic to the subject at hand.
Rilevanza
The word rilevanza is used to describe the importance, weight, or impact of an event, fact, or object. You use this word when you want to emphasize that something matters a great deal or has a significant effect on a specific situation.
Questo documento ha una grande rilevanza per le indagini in corso.
(This document has great significance for the ongoing investigation.)
Il giudice ha respinto la prova per mancanza di rilevanza.
(The judge rejected the evidence due to a lack of importance.)
La sua opinione non ha alcuna rilevanza in questa decisione.
(His opinion has no weight in this decision.)
Dobbiamo discutere un argomento di rilevanza nazionale.
(We must discuss a topic of national importance.)
Hanno scoperto un reperto archeologico di estrema rilevanza.
(They discovered an archaeological artifact of extreme significance.)
Pertinenza
The word pertinenza is used to indicate that something is logically connected, appropriate, or strictly on-topic. You use it to describe whether a remark, a piece of information, or an action actually belongs to the subject being discussed or falls within someone's specific area of responsibility.
La tua domanda non ha alcuna pertinenza con il tema della lezione.
(Your question has no connection to the theme of the lesson.)
Valuteremo la pertinenza dei dati prima di scrivere il rapporto.
(We will evaluate the applicability of the data before writing the report.)
Questo problema non è di mia pertinenza quindi chiedi al direttore.
(This problem is not within my area of responsibility so ask the manager.)
Il comitato dubita della pertinenza di quel commento durante la riunione.
(The committee doubts the appropriateness of that comment during the meeting.)
Il professore ha verificato la pertinenza delle fonti citate nella tesi.
(The professor verified the connection of the sources cited in the thesis.)
Summary
To summarize, choose the word rilevanza when you need to express how important or significant a particular thing is. Choose the word pertinenza when you need to show that something is logically connected to the topic, appropriate for the context, or falls within the correct scope of responsibility.