Instruments to assess diabetes knowledge, skills and attitudes of people living with diabetes mellitus: A COSMIN-based systematic review

Aims: Since knowledge, skills, and attitudes influence the adherence to self -care behaviours, the purpose of this review was to identify available instruments that measure diabetes knowledge, skills or attitudes of people living with this health condition and to evaluate their measurement properties. Methods: A systematic search was conducted in PubMed, EMBASE, SCOPUS, Web of Science and CINAHL databases. The methodological quality of the included studies was assessed by the Consensus -based Standards for the selection of health Measurement Instruments. Risk of Bias checklist. The results of each study were rated by the updated criteria for good measurement properties and the quality of evidence was graded using a modified Grading of Recommendations Assessment, Development, and Evaluation approach. Results: This review included 38 instruments that assess diabetes knowledge (n = 26) or skills (n = 6) or attitudes (n = 5) or both three constructs (n = 1). About 40% had satisfactory results for relevance, comprehensiveness, and comprehensibility, and about 30% had unsatisfactory results for comprehensiveness, but these results were supported by very low evidence. Most studies showed indeterminate results for structural validity (50%), internal consistency (98%) and reliability (84%). Instruments that had satisfactory results for construct validity and reliability were supported by low to very low evidence. One responsiveness study was identified, and the result was satisfactory, but supported by low evidence. The Diabetes Knowledge Questionnaire is the instrument with best evidence for use. Conclusions: To plan more assertive interventions, researchers need to follow up guidelines to develop instruments with good quality of the measurement proprieties.