OBJECTIVE:To assess differences in the valuation of eight schizophrenia-related health states using a multi-attribute utility instrument, the Assessment of Quality of Life Questionnaire (AQoL), and two scaling techniques, the time trade-off (TTO) and a visual analogue scale (VAS). METHODS: Eight schizophrenia-related health state scenarios based on severity of symptoms and medication side effects were presented to 87 participants from the general population. Scenarios were: A) ‘good' function with no movement disorders (extrapyramidal symptoms); B) ‘good' function with movement disorders; C) ‘poor' function with no movement disorders; D) ‘poor' function with movement disorders; E) hospitalised relapse with no movement disorders; F) hospitalised relapse with movement disorders; G) post-hospitalisation with no movement disorders; and H) post-hospitalisation with movement disorders. Participants, once educated about schizophrenia, were asked to value each health state using the AQoL, TTO, and a VAS. RESULTS: Mean utility values for all health states ranged from 0.62 to 0.05, 0.72 to 0.54 and 0.74 to 0.19 for the AQoL, TTO and VAS, respectively. For each instrument or scale the rank order of utility values was consistent with the severity of symptoms, with more severe symptoms producing lower scores. Patients experiencing EPS had lower utility scores and hospitalisation also producing utility decrements. There were differences between the global results for AQoL, TTO and VAS (p<0.001, Kruskal-Wallis test) and differences between the utility measures for each health state, except between the TTO and VAS results for health state A (p=0.655), and the AQoL and VAS results for health state G (p=0.094). CONCLUSION: Utility values varied with severity of health state (symptoms) and in most cases differed significantly between instrument and/or scale. For schizophrenia, the AQoL was most sensitive to differing symptom severity, as assessed by the general population. However, further research comparing the different utility instruments is required in this disease area.