You can't really swap least and minimum. Because least does not have a minimum level below which the compared or the comparator can not go. Minimum would be used to indicate the lowest price for example. Least would be used to indicate a result as in your apparent example. However there is not the full complete ending to the context to give a full answer to your question. Least would be comparing plurals the (the thing/item that is the least would be a singular) unless specified "the least I would be able to sell supply is 100 grams" . 100 grams is plural, but "the least" might be considered as a single amount.

Olá, Luiz. I think you may mean “minimal” — are you translating from Portuguese? “Least” does not work at all in that sentence.

Hi Gary, here is the original sentence: ''However, by analysing our data in a descriptive manner, we managed to observe least correlations of anxiety (r = 0.217) and stress (r = 0.148) symptoms with the variable ‘’Time since diagnosis’’. Do you think I wrote it correctly?

correlation, correlation coefficient or relationship may be positive , negative or zero; also you may use minimum instead of least.

I would also prefer to see the end of the sentence (if there is something else indicated by the ellipsis)