<qa>  What is a double blind placebo controlled add on standard therapy trial?This is a randomized, double blind placebo controlled add on standard therapy trial with vitamin B12, B6 and folic acid, in young patients between 15-25 presenting to ORYGEN Youth Health with a first psychotic episode . Vitamins B12 , B6 and Folate will be compared with placebo added to standard treatment for a period of 12 weeks in a double blind fashion. Primary outcome measures will be psychopathology and cognition CogState and MATRICS. Secondary outcome measures will be tolerability and safety measures drop-out rates, general side effect scale UKU. 