Table 4 Psychometric properties of LMC SCPI index for 25 items
Measure | Statistic | |
|---|---|---|
Reliability | ||
Internal consistency for subscales | ||
Skills | Cronbach’s alpha (95% CI) | 0.85 (0.81- 0,89); 9 items |
Confidence | Cronbach’s alpha (95% CI) | 0.83 (0.78–0.87); 8 items |
Preparedness | Cronbach’s alpha (95% CI) | 0.88 (0.84–0.91); 8 items |
Test-retest reliability | Pearson’s correlation coefficient; p-value | 0.48; <0.001*** |
Validity | ||
Convergent validity | ||
Diabetes Empowermenta | Pearson’s correlation coefficient; p-value | 0.28; 0.002** |
Michigan Knowledge | Pearson’s correlation coefficient; p-value | 0.21; 0.019* |
PHQ9 | Pearson’s correlation coefficient; p-value | -0.167; 0.068 |
Construct validity | ||
Age | Pearson’s correlation coefficient; p-value | -0.12; 0.173 |
Gender | ANOVA; F test, df; p-value | F[1, 118] = 0.018; 0.893 |
Level of education | ANOVA; F test, df; p-value | F[4,81] = 0.858;0.493 |
Ethnicity | ANOVA; F test, df; p-value | F[9,110] = 1.23; 0.286 |
Duration of diabetes | Pearson’s correlation coefficient; p-value | 0.11; 0.256 |
Type of diabetes | ANOVA; F test, df; p-value | F [1, 108] = 5.433; 0.022* |
A1C | Pearson’s correlation coefficient; p-value | -0.18;0.062; 104 participants |