Super useful post about filtering and best practice within Backbonejs. http://tech.pro/tutorial/1519/rendering-a-filtered-backbonecollection
Effectively best practice for future planning is to put filtering into the collection – but to be careful that you don’t update the original collection with the filter as from then on out you’re working off a filtered collection rather than the original. So its best to put your filtered content into separate collections and pass it to views from there rather than the original. Good to know!