Perceptions of Usability and Design for Prefilled Insulin Delivery Devices for Patients With Type 2 Diabetes

Abstract

Although many patients with type 2 diabetes are initially managed through lifestyle modification, most eventually require insulin therapy. However, insulin initiation is often delayed because of factors such as patients' resistance to insulin therapy and worries about injections. Such delays affect glycemic control, have a direct effect on patient encounters, and may affect medication adherence. Insulin pen delivery systems may address some of these concerns. This study had two phases. First, semi-structured qualitative interviews were conducted to identify the most important features of insulin delivery devices for prandial use from the perspective of patients (n = 8) and health care professionals (HCPs; n = 10). From phase 1, a 26-item questionnaire was developed. In phase 2, patients (n = 33 insulin naive, n = 78 pen users) and HCPs (n = 151) were asked to indicate the most important features to them in insulin delivery devices. Patients then simulated injection using three different pens (SoloSTAR, KwikPen, and FlexPen) and ranked them based on the same features. The most important features were knowing that the entire dose has been injected, ease of reading the dose correctly, and ease of correcting if the dose is over-dialed. In the simulation study, KwikPen and SoloSTAR scored significantly higher (paired t test, P < 0.05) than FlexPen on “knowing if you have injected the entire dose” (mean score out of 10: KwikPen, 8.9; SoloSTAR, 8.6; and FlexPen, 8.4). No other significant differences among the pens were noted in usability or design, and the mean ranking (from 1 to 3) of the pens was similar (KwikPen, 2.0; FlexPen, 2.1; and SoloSTAR, 1.9). By identifying which insulin delivery pens offer these features, HCPs can choose the most appropriate delivery device for patients, which may lead to earlier insulin initiation, greater patient adherence, and better clinical outcomes.

Patient Perceptions of and Preferences Between Characteristics of Injectable Diabetes Treatments

“…A range of studies assessing preference among insulin and GLP-1 receptor agonist injection devices have found that patients preferred devices that were perceived as easier to use [48,67,68]. As in the current study, previous research has also shown that patients value features that instill greater confidence that they are receiving the correct dose [69,70]. The current results add to these previous findings by providing insight into preferences across a wider range of injectable treatment attributes.…”

Factors Affecting Performance of Insulin Pen Injector Technology: A Narrative Review

“…39 Results of a survey of 504 people with type 2 diabetes in the United States or the United Kingdom identified confidence in administering the correct dose (59.5% of participants), ease of selecting the correct dose (53.2% of participants), overall ease of use (47.4% of participants), and frequency of injections (44.2% of participants) as the most important features that would determine their choice of an injection device (selected from 17 attributes). 43 These results confirmed previous reports indicating that receiving the correct insulin dose is the primary concern of individuals using insulin pen injectors 46,47 and that the likelihood of people using a device increases with their perception of its ease of use. 45,48,49…”

Psychometric evaluation of the Diabetes Injection Device Experience Questionnaire (DID-EQ) and Diabetes Injection Device Preference Questionnaire (DID-PQ)

“…The DID-EQ addresses a gap in PRO measures for the assessment of treatment experiences among patients with type 2 diabetes. The previous measures are either general instruments [ 31 ] or questionnaires specifically targeted toward insulin treatment [ 1 , 2 , 4 , 24 , 25 , 32 – 36 ]. The general instruments, such as the DTSQ [ 31 ], may be used with a broad range of treatments, but they do not yield specific information on injection devices.…”