IR35 Ongoing Checks

Hi Everyone! Firstly I’ve been a lurker for awhile and find this forum a massive help in my standalone HR Generalist role so thank you We are a growing organisation which has employees but also self-employed Associates who complete work on our behalf. When determining employment status what processes do you have in place and how often will you check this going forward…annually? With the amount of Associates we have we are wanting to put in a straightforward process which stops us falling foul of HMRC! Thanks in advance