Table 1.

PICO scheme of the systematic review.

Patient, population or Problem	Intervention	Comparison	Outcome
What are the characteristics of the patients or population?	What interventions are we considering?	What is the alternative to the intervention?	What are the relevant outcomes?
Psychotic disorders, including schizophrenia, bipolar disorder and schizophrenia-spectrum psychotic disorders with hyperprolactinaemia.	Four strategies for lowering prolactin: Switching antipsychotics Adding aripiprazole Adding other dopamine agonists (e.g., cabergoline, bromocriptine) Adding metformin	Placebo or maintaining antipsychotic treatment (randomized clinical trials with comparison arms will be included in the meta-analysis). Uncontrolled studies (with comparator) will be included in the systematic review if there is information regarding changes in prolactin with the strategy.	Reduction in prolactin plasma concentrations.