The OET writing task asks you to read case notes and write a letter, such as a referral or discharge letter, for a named reader. Choosing the right information and presenting it clearly matter as much as grammar.
These articles cover planning an OET letter, selecting case notes, common mistakes, the grades registration bodies ask for, and ways to get useful feedback on practice letters.
OET C+ Writing for the NMC: what a score of 300 means, why a short letter can mean a resit, and how nurses can plan and practise a clinical letter for it.