Assessing quality of life in patients with schizophrenia in an acute psychiatric setting: Reliability, validity and feasibility of the EQ-5D and the Q-LES-Q

Background: Quality of life (QoL) is considered an important outcome of treatment in psychiatry. Two QoL instruments, the EuroQoL-5D (EQ-5D) and the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q), have been increasingly used among patients with schizophrenia. Aims: The aim of this study was to investigate the reliability, validity and feasibility of the EQ-5D and the Q-LES-Q among patients with schizophrenia and related disorders (n = 311) in the most acute stage of their illness. Methods: The study was carried out in nine acute psychiatric wards of two psychiatric hospitals in Finland. The instruments' internal consistency, construct validity and missing values were evaluated. Results: Our findings show high internal consistency for the Q-LES-Q (Cronbach's alpha 0,89). For the EQ-5D, the Cronbach's alpha value was minimally acceptable (0.63) taking in to consideration the low number of items. Lower overall functioning indicated poorer QoL measured by the EQ-5D (U = 3098, P < 0.001) or the Q-LES-Q (U = 3357, P < 0.001). Missing values in the EQ-5D ranged from 6% to 7% and in the Q-LES-Q from 6% to 31%. Conclusion: Our results suggest that both QoL scales are reasonably reliable, valid and feasible in this patient group. The decision regarding which instrument to use would depend on clinical or research questions. When more detailed information for patients' satisfaction with QoL is needed then the Q-LES-Q would be a better choice, whereas if the primary interest is to briefly assess patients' QoL problems related to health status the EQ-5D would be a better choice.