Injection Technique: Development of a Novel Questionnaire and User Guide

Approximately 200 million people worldwide use injectable therapies as part of diabetes management. There appears to be a significant gap between insulin injection technique recommendations and injection practice for many. We aimed to develop and validate a novel, brief, self-administered injection technique assessment questionnaire.

An iterative codesign process was conducted. Focus groups and interviews with adults (or parents of children) with type 1 or type 2 diabetes and health care providers (HCPs) elicited views and refined the tool for broader distribution to the target audience. Questions addressed ease of understanding; relevance; included items and potential missing questions; feelings about diabetes; and any discomfort or judgment felt when completing the tool. A user guide was developed with cognitive interviewing performed to ensure relevance, acceptability, readability, and understanding. Statistical analyses included propensity score matching to identify a subset of the Worldwide Injection Technique Questionnaire with similar characteristics. Boruta feature selection, Cramér's V, and multiple correspondence analysis were conducted.

HCPs and 16 people with diabetes participated in the initial focus groups and interviews. Questions were reported as clinically relevant, simple to complete, "about the right length," relevant, and easy to understand. A total of 267 participants completed the survey reviewing the questionnaire. A further 16 participants underwent cognitive interviews. The complete resource was then reviewed by another 23 people with diabetes as a final check for completeness and usability. Statistical analyses demonstrated high validity and reliability.

This novel resource is clinically relevant, acceptable, and easy to use as both a clinical tool and a self-assessment tool for people using injectable therapies for diabetes.