Abstract
Background To benefit from real-time continuous glucose monitoring (rtCGM), users need practical
skills and in-depth knowledge to analyze the glucose data appropriately and adapt
insulin therapy accordingly. To assess the user’s knowledge about rtCGM, a psychometric
knowledge test was developed and evaluated.
Method Experts on the use of rtCGM systems defined central knowledge contents in a Delphi
process and developed a knowledge test comprising 40 multiple-choice items. For test-statistical
review, people with insulin-treated diabetes and members of diabetes teams answered
the knowledge test.
Results The 122 diabetes team members (age 46 (11) years; mean (SD)) and the 111 people with
insulin-treated diabetes (age 42 (14) years, diabetes duration 20 (14) years, users
of insulin pumps 64 %, previous usage of rtCGM 38 %, HbA1c 8.0 % [95 % CI 7.7–8.3]
(64 mmol/mol [60–67]) had different levels of experiences using rtCGM systems. The
internal consistency (Cronbach’s alpha) of the knowledge test was 0.92 for the whole
sample, for people with diabetes 0.94, and for diabetes team members 0.84. Item difficulty
ranged between 0.12 and 0.88 in people with diabetes and between 0.27 and 0.97 among
diabetes team members. On average, people with diabetes answered 24.1 (9.9) items
correctly, diabetes team members 29.2 (5.2) (p < 0.001); people with diabetes and
previous rtCGM-experience had a higher knowledge compared to people without previous
experience (29.2 (6.2) vs. 21.0 (10.4) (p = 0.001)). The quality of glucose control
(measured by HbA1c) of the people with diabetes was significantly associated with
the sum-score of the questionnaire (rho = –0.48, p < 0.001).
Conclusion The “rtCGM-Profi-Check” knowledge test provides high internal consistency, high selectivity,
and content validity. It is suitable for objective, reliable, and valid assessment
of the indispensable knowledge of people with diabetes to use different rtCGM systems
successfully. The questionnaire is manufacturer-independent and is suitable to evaluate
the needs and success of rtCGM education among persons with diabetes.
Key words real-time CGM - diabetes - education - knowledge test - questionnaire
Schlüsselwörter real-time-CGM - Wissenstest - Diabetes - Schulung - Fragebogen
