Scales to Measure Perceived Control Developed Specifically for People with Tablet-treated Diabetes

Scales to measure perceived control of tablet-treated diabetes were adapted from a measure designed previously for insulin users. Development of the new scale is described and the psychometric properties are examined with responses from 187 tablet-treated patients. The scales consist of seven subscales which may be combined to provide three composite scores indicating the extent to which respondents perceive Personal Control, Medical Control, and Situational Control over their diabetes. Relationships between subscales and composite scores were similar to those found previously for insulin users. Patients were significantly more likely (p less than 0.001) to make attributions to Personal Control for their diabetes management rather than to Medical or Situational Control. As before, predictable biases were found in attributions to positive and negative outcomes. Correlations with medical and other psychological variables indicated that, as expected, stronger perceptions of Personal Control were associated with lower HbA1 levels (r = -0.14; p less than 0.05), lower percent ideal body weight (r = -0.24; p less than 0.01), less Anxiety (r = -0.15; p less than 0.05), greater Positive Well-being (r = 0.21; p less than 0.01) and greater Satisfaction with treatment (r = 0.34; p less than 0.001). Complementary relationships were found with the measure of Situational Control. Wallston and Wallston's speculative Locus of Control typology was investigated using the new measures, and the findings provided support for the value of this approach.