Thai version of the Questionnaire for Diabetes-Related Foot Disease (Thai Q-DFD): validity and reliability

To reduce diabetic foot complications, an annual screening of diabetes-related foot disease (DRFD) should be promoted. The screening tool as the Thai translated Questionnaire for Diabetes-related Foot Disease, Thai Q-DFD, has been established. The study was designed to assess the validity and reliability of the Thai Q-DFD before practical use in the community.

One hundred and thirty-nine persons with diabetes volunteered in a concurrent validity testing for agreement in diagnosis between the Thai Q-DFD and the standard clinical examinations. The test-retest reliability (a stability of a tool over time between three days apart) was assessed in 50 volunteers. The agreement in either validity or reliability test was evaluated using kappa coefficient.

The screening diagnosis as DRFD by the Thai Q-DFD substantially agreed with that by the standard clinical examinations (kappa = 0.71). The Thai Q-DFD also showed high sensitivity (0.92) and specificity (0.78). Additionally, the Thai Q-DFD presented good test-retest reliability for DRFD diagnosis (kappa = 0.74).

The Thai Q-DFD is comparable to the original English version in terms of concurrent validity and test-retest reliability. Therefore, it can be used for a screening of DRFD in Thai people.