Purpose: The aims of this study were to develop a new instrument for measuring self-management with
a hierarchical structure [the Diabetes Self-Management Scale (DSMS)] in patients with type 2 diabetes,
and evaluate its psychometric properties.
Method: The DSMS instrument was developed in three phases: (1) conceptualization and item generation;
(2) content validity and pilot testing; and (3) field testing of its psychometric properties. A convenience
sample of 473 participants was recruited in three university hospitals and one regional health
center, South Korea.
Results: Exploratory and confirmatory factor analyses yielded two second-order component models
explaining the common variance among six first-order factors. Principal axis factoring with a varimax
rotation accounted for 60.88% of the variance. Confirmatory factor analysis of the hierarchical structure
revealed the following fit indices: χ2/df = 1.373, standardized root-mean-square residual = .050,
goodness-of-fit index = .935, incremental fit index = .975, comparative fit index = .974, and root-meansquare
error of approximation = .039. All Cronbach' a values for internal consistency exceeded the criterion
of .70. All of the intraclass correlation coefficients for test-retest reliability exceeded .70 except
that for the taking-medication subscale. The components of the DSMS were moderately correlated with
the comparator measures of self-efficacy and health literacy administered for convergent validity.
Conclusion: The DSMS is a new instrument for measuring the complex nature of self-management in
patients with type 2 diabetes, comprising 17 items scored on a five-point Likert scale. The DSMS exhibits
satisfactory psychometric properties for five reliability and validity metrics, and so is a suitable instrument
to apply in both research and clinical practices.