Efficacy was measured with the Psychotic Symptom Rating Scales ( PSYRATS ) Delusions Rating Scale ( DRS ) , and with specific secondary measures referring to persecutory ideas and ideas of social reference ( the Green Paranoid Thoughts Scale , GPTS ) , cognitive insight ( the Beck Cognitive Insight Scale , BCIS ) , subjective experiences of cognitive biases ( the Davos Assessment of Cognitive Biases Scale , DACOBS ) and metacognitive beliefs ( the 30-item Metacognitions Questionnaire , MCQ-30 ) .