An Insight into Patient Usability Preferences for Injection Devices
A synopsis of a recent MDU research paper,
Natalie Shortt, Medical Device Usability Ltd.
Mainstream administration of injected medication has been practiced near a century, as the anniversary of the invention of insulin as medicine draws near (discovered 1921). The design of the syringe and the injection devices that have since followed have had few usability-orientated enhancements, however modern technology has lent its hand to the improvement of safety of medical devices. In turn patients are allowed more independence. This advance in technology has meant a shift in the primary user from a trained professional to… anyone at all. Usability testing provides evidence that the risk associated with use is reduced to a residual level.
We at Medical Device Usability conducted research with the aim of providing new insights into what usability features patients prefer, and what drives these preferences. Ultimately, this study sought to advance the theoretical knowledge of usability of injection devices when the intended user is the patient.
Methods applied prior to data collection
The inclusion criteria for participation was to have a condition where it was possible to be prescribed or were already prescribed self-injected medication. If a participant did not have a qualifying medical condition, then they were excluded. Participants were approached after participating in other usability studies. They were asked if they would be happy to complete an optional questionnaire as a separate piece of research.
The questionnaire was designed to capture participant preferences for a series of design and aesthetic features that contribute to an injection device’s user interface. Dichotomous questions were used, e.g. ‘Would you prefer an injection device to be silent or to make a sound?’ Profiling data was also captured for each participant. The design features chosen were done so based on their relevance to the usability of the user interface. These features cover usability (size of device, audible feedback and speed of injection) and features that could influence psychological reception of an injection device (needle visibility and aesthetics). Participants were also given the opportunity to write a brief explanation for each preference chosen. This was to gather insight into what drove the patient’s preferences.
Methods applied to data analysis
A mixed methodology was applied. Trends were first identified in quantitative data and then qualitative data was analysed to identify underlying drivers.
Each dichotomous question was analysed using an inductive approach (Thomas, 2006); the research objectives were defined as; ‘to understand why patients prefer the design features that they do’, and ‘to determine if participant’s preferences were driven by the same motivations’. Research findings emerged from the most frequent trends that addressed the research objectives. As usability testing seeks to understand the user’s perspective, using the most frequent trends as opposed to the analyst’s interpretation meant that the participants’ views led the findings. These frequent trends were grouped together as general (upper-level) categories. The categories were refined into specific (lower-level) categories.
A focus was taken on the qualitative data, and the outcomes showed that patient users share drivers of preference. A concept emerged from the data of positive and negative perceptions of the injection system and the design features. In brief these concepts are:
‘Positive’ categories are considered as conveying a want to self inject – for example, seeing the needle prior to injecting to ensure a ‘safe injection technique’.
‘Negative’ categories tend to refer to a person’s avoidance of injecting, such as not seeing the needle prior to injecting due to a fears of needles and lack of self-confidence.
The findings of the study were written up and then submitted to the Ergonomics and Human Factors conference 2017 hosted by the CIEHF. The paper is included in the proceedings and the proceedings can be purchased here;
Thomas, D. R., (2006). A General Inductive Approach for Analyzing Qualitative Evaluation Data. American Journal of Evaluation, 27(2), 237-246. doi: 10.1177/1098214005283748.