Purpose: Self-care is essential for hypertensive individuals to promote optimal health and illness treatment.
We developed the Thai Self-Care of Hypertension Inventory (SC-HI) version 2.0 from the original
US version using a multi-stage approach for cross-cultural adaptation. Scales previously studied outside a
US context had different dimensions and factor solutions. Therefore, we examined the Thai SC-HI's
factorial validity, construct validity, and internal reliability within a Thai context.
Methods: We administered a cross-sectional survey with hypertensive patients in 10 primary care settings,
and conducted exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) on two sets
of separate samples from each of five sites to examine the model's factorial validity and construct validity.
We estimated scale reliability with Cronbach's alpha and McDonald's omega coefficients.
Results: Participants were predominantly female, older adults, with mean age 66 years (SD ¼ 11.94;
range 36e97 years). The self-care maintenance scale had three factors and demonstrated good fit
when the error covariances were respecified. The two-factor self-care management scale had different
factorial solutions compared to previous models. The CFA result showed good fit indices for the Thai,
original US, and Brazilian models. The self-care confidence scale was unidimensional, with partially
supported fit indices that improved after we respecified the error covariances. Reliability coefficients
estimated by difference methods were nearly equal: slightly lower than desired for self-care maintenance
(.68e.70) and inadequate for self-care management (.62e.65); self-care confidence reliability
was adequate (.89e.90).
Conclusion: The Thai SC-HI has good psychometric characteristics and reflects the original instrument's
theoretical basis.