The patient-perceived difficulty in diabetes treatment (PDDT) scale identifies barriers to care

The objective of this study is to describe the design and validation of a newly developed brief, treatment-focused scale for use with type 1 and type 2-diabetes, exploring patient-perceived difficulties that are associated with treatment.

The content of the construct was derived from consultation with experts, from existing instruments and the literature, as well as from diabetic patients. The original draft was comprised of 11 attributes. Based on an interim analysis, an additional 12th attribute was added. The final scale was tested on 988 diabetic patients from 25 practices in Israel. Respondents also completed a diabetes-specific quality of life (QoL) questionnaire and indicated their current perceived overall health status.

The patient-perceived difficulty of diabetes treatment (PDDT) scale contains 12 items reflecting diabetes-treatment characteristics: adherence to self-monitoring of glucose schedule, frequency of self-monitoring of glucose, adherence to medication administration schedule, frequency of medication administration, multiple number of medications, synchronization between meals and medications, dependence on the medications, pain associated with treatment, diet restrictions, self-care, multiple healthcare providers, and costs of treatment. Response rate to all attributes was very high. Construct validity was shown by significant correlations between PDDT attributes and diabetes-specific quality of life (r = 0.31-0.46) and self-report adherence to recommended treatment (r = 0.14-0.28), as well as between overall perceived difficulty and diabetes-specific quality of life (r = 0.60). Furthermore, the PDDT items showed discriminant capabilities with respect to known groups of patients.

The PDDT scale is a simple and valid instrument that may assist in identifying potential barriers in adherence to recommended treatments and to new treatment options.