Clinical impact of reducing the frequency of clozapine monitoring: controlled mirror-image cohort study.

Background: To minimise infection during COVID-19, the clozapine haematological monitoring interval was extended from 4-weekly to 12-weekly intervals in South London and Maudsley NHS Foundation Trust.

Aims: To investigate the impact of this temporary policy change on clinical and safety outcomes.

Method: All patients who received clozapine treatment with extended (12-weekly) monitoring in a large London National Health Service trust were included in a 1-year mirror-image study.