Development and testing of the Multidimensional Trust in Health Care Systems Scale

To describe the development and psychometric testing of the Multidimensional Trust in Health Care Systems Scale (MTHCSS).

Scale development occurred in 2 phases. In phase 1, a pilot instrument with 70 items was generated from the review of the trust literature, focus groups, and expert opinion. The 70 items were pilot tested in a sample of 256 students. Exploratory factor analysis was used to derive an orthogonal set of correlated factors. In phase 2, the final scale was administered to 301 primary care patients to assess reliability and validity. Phase 2 participants also completed validated measures of patient-centered care, health locus of control, medication nonadherence, social support, and patient satisfaction.

In phase 1, a 17-item scale (MTHCSS) was developed with 10 items measuring trust in health care providers, 4 items measuring trust in health care payers, and 3 items measuring trust in health care institutions. In phase 2, the 17-item MTHCSS had a mean score of 63.0 (SD 8.8); the provider subscale had a mean of 40.0 (SD 6.2); the payers subscale had a mean of 12.8 (SD 3.0); and the institutions subscale had a mean of 10.3 (SD 2.1). Cronbach's alpha for the MTHCSS was 0.89 and 0.92, 0.74, and 0.64 for the 3 subscales. The MTHCSS was significantly correlated with patient-centered care (r = .22 to .62), locus of control-chance (r = .42), medication nonadherence (r = -.22), social support (r = .25), and patient satisfaction (r = .67).

The MTHCSS is a valid and reliable instrument for measuring the 3 objects of trust in health care and is correlated with patient-level health outcomes.