Testing the Measurement Equivalence of the Chinese Dispositional Flow Scale–2 Between Schizophrenia and General Populations in Taiwan

PURPOSE: This study aimed to test the measurement equivalence of the Chinese Dispositional Flow Scale–2 (DFS–2) between schizophrenia and general populations, exploring the major characteristics of people with schizophrenia that facilitate flow experience in daily activity participation.

BACKGROUND: According to flow theory, flow is an optimal psychological state that occurs when people perform and are involved entirely in an activity, including daily activities (e.g., play or work), and that helps increase feelings of well-being. The DFS–2 was developed to assess an individual’s dispositional flow tendency while participating in daily activities and contains 36 items, including four items for each of nine dimensions of flow.

Given that the DFS–2 was developed with the general population, little is known about differences in results obtained by the schizophrenia population, who may have attention deficits and motivation problems when participating in activities. Testing measurement equivalence helps determine whether an instrument is equivalent across two independent groups, focusing on the unchanged operation of the factor loadings. In testing for the equivalence of factor loadings, the parameters for the first group are freely estimated, and then the factor loadings for the other group are constrained equal to those of the first group.

METHOD: In this cross-sectional design study, we enrolled 204 adult participants in two groups. The schizophrenia group included 100 adults diagnosed with schizophrenia or schizoaffective disorder from psychiatric outpatient clinics, day hospitals, and vocational rehabilitation programs in Taipei, Taiwan; the control group included 104 participants without severe mental illness from the same settings (e.g., staff, volunteers, interns, community residents).

Instruments included the Chinese versions of the Dispositional Flow Scale, the Flow State Scale, the General Causality Orientation Scale, the Activity Participation and Restriction Questionnaire, the Satisfaction With Life Scale, the Beck Depression Inventory–II, Chu’s Attention Test, and the Leisure Satisfaction Scale. We also used the Positive and Negative Symptom Scale for the participants in schizophrenia group.

Lisrel 9.2 (Scientific Software International, Skokie, IL) was used to analyze the data. We first conducted exploratory factor analysis and confirmatory factor analysis (CFA) for each group. Then we conducted multigroup CFA with the CFA model for the control group as a standard, including factor loadings, factor correlations, and error variances invariant, and then held parameters of the schizophrenia group equal to the control group with Wald’s t test to drop an insignificant structural parameter and modification index to add an additional meaningful structural parameter. Root mean square (RMR), standardized RMR (SRMR), and goodness of fit index (GFI) were administered to assess the adequacy of fit. Then we alternatively applied the schizophrenia group as the standard to do multigroup CFA on the same procedures and criteria.

RESULTS: With the control group as the standard, the results of multigroup CFA indicated that the cross-group equivalence was poor (RMR = .119, SRMR = .093, GFI = .474); 43 items for the schizophrenia group were added on this constrained model. Moreover, with the schizophrenia group as the standard, the results of multigroup CFA showed that the cross-group equivalence was better (RMR = .210, SRMR = .201, GFI = .826); six items for the control group were added on this constrained model.

CONCLUSION: We found that items related to time perception, concentration, executive functions, and motivation may have caused major differences between the schizophrenia and control groups in dispositional flow tendency.

IMPACT STATEMENT: This study suggests that occupational therapy practitioners should address the problems of cognitive, motivational, and temporal adaptation for people with schizophrenia when encouraging them to experience flow in daily activities. The results of this study may serve as part of the evidence to establish a foundation for further inquiry regarding occupational therapy intervention outcomes and cross-cultural differences.

References

Byrne, B. M. (2008). Testing for multigroup equivalence of a measuring instrument: A walk through the process. Psicothema, 20, 872–882.

Green, M. F. (2016). Impact of cognitive and social cognitive impairment on functional outcomes in patients with schizophrenia. Journal of Clinical Psychiatry, 77, 8–11. https://doi.org/10.4088/JCP.1006e12

Jackson, S. A., Eklund, R. C., & Martin, A. J. (2010). The flow manual. Menlo Park, CA: Mind Garden.

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