Construct Validity of the Quality of Life for Patients with Schizophrenia

Objective: Health-related quality of life (HRQoL) has become one of the most valuable indicators of treatment in patients with schizophrenia. The purpose of this study was to establish the construct validity of eight domains in a HRQoL scale. Methods: From four psychiatric rehabilitation centers, 237 patients were chosen for participation in the study. Inclusion criteria were a DSM-IV-R diagnosis of schizophrenia. Quality of life was measured using the Quality of Life for Mental Disorders (QoLMD) scale. Structural equation modeling (SEM) was chosen to investigate the construct of the QoLMD. Results: This model of HRQoL for patients with schizophrenia was acceptable (Chi-square=1004.484 (df=789), p=0.192, GFI=0.852, RMSEA=0.034, TLI=0.940). The relationship between eight domains of the QoLMD can be interpretive into three parts: (A) under family support, patients with schizophrenia had significantly directly related to mental and physical health (β=0.849 and 0.738) and significantly indirectly related to HRQoL (i.e., life satisfaction, autonomy, health maintenance); (B) under physical health, schizophrenia patients had significantly directly related to HRQoL (β=0.745-0.921) (p＜0.001); and (C) under mental health had significantly directly related to physical health (β=0.217) (p＜0.05). Conclusion: The SEM revealed that HRQoL was interpreted by the pathways between eight domains of QoLMD, and therefore it made clinical therapists understood clearly about the correlation and mutual-influential pathway between HRQoL and QoLMD.