Check Your Health was constructed as four-two-sided vertical thermometers (0–100) measuring physical and emotional health, social well-being and quality of life today and before onset of diabetes. Burden of diabetes was calculated as the difference between the two scores (today and before onset of diabetes). The aim was to examine concurrent and discriminant validity and reliability of Check Your Health in a convenience sample of 180 people with diabetes, who visited the diabetes clinic during a 3-month period. A randomly selected subsample of 43 of the 180 patients responded to the questionnaire twice (test–retest). Besides Check Your Health, three additional questionnaires were mailed to the patients, the EVGFP scale (EVGFP stands for Excellent–Very good–Good–Fair–Poor health) for measuring concurrent validity, the Diabetes Empowerment Scale (Swe-DES-23) and an attitude measure, Semantic Differential in Diabetes (SDD) for calculation of discriminant validity. There was significant agreement between Check Your Health and the five EVGFP health groups. The instrument discriminated well between patients with and without late diabetic complications. The measure on burden of diabetes showed that the higher the burden of diabetes, the lower the quality of life. The same pattern was found for both Swe-DES 23 and SDD; the higher the burden, the lower the sense of empowerment and the lower the burden, the more positive the attitudes towards diabetes. Check Your Health showed good stability (0.88–0.68). The results indicate that Check Your Health can be used as an acceptable and sufficiently accurate method for detecting health distress in people with diabetes.