Injection Naïve: The New Unicorn?

If you are a human factors engineer, medical device UX researcher or a healthcare market research firm, you have surely experienced a growing difficulty fulfilling injection naive quotas for your injection device usability studies. There has been a dramatic shift over the past decade in recruitment incidence within the injection naive vs injection experienced patient and caregiver segments.

Historically, when designing research outside of diabetes, injection experience was the low incidence cohort. However, over the past decade the pendulum has swung significantly in the other direction making inclusion of true lifetime injection naive patients and caregivers the needles in a haystack. In order to successfully execute injection device usability studies, it is important to understand the current climate as related to injection experience within the US population.

Why The Shift?

There are numerous factors leading to the injection experience incidence shift over the past ten years.

• Diabetes continues to increase in diagnosis rate annually and is estimated to now affect 12% of the US population rising to 29% in the elderly. While there is an abundance of treatment modalities available, insulin is the #1 prescribed injectable in the US. 23% of diabetic patients self administer insulin.
• The rise in autoimmune conditions accompanied by the emergence of self-administered biologics. 10% of the US population is affected by an autoimmune condition. Of those diagnosed, 6% are prescribed an injectable biologic.
• Approximately 10 million patients in the US are diagnosed with osteoporosis. Forteo and Prolia, both injectable treatments and prophylactic approaches to treating osteoporosis are delivered via at-home injection.
• Hormone replacement therapy diagnostics, education, accessibility and affordability has led to 20 million Americans being placed on an HRT protocol with 1.2 million inclusive of an injectable therapeutic.
• Allergies and anaphylaxis, especially in children, have risen significantly over the past decade. The CDC now estimates 1 in 4 children have a diagnosed allergy. With that, there is an elevated population of children, and subsequently adults, trained to administer an EpiPen.
• The growing popularity and now widespread access of injectable GLP-1 agonists will likely be the anchor forever sinking injection naive recruitment feasibility. Millions of Americans have now at least tried an injectable GLP-1 for diabetic management and/or weight loss. These statistics are expected to continue to climb due to the abundance of recently confirmed positive clinical outcomes and widening of regulatory approvals.

Tightened Definition of “Injection Naive”

Despite the growing adoption and prescribing of patient delivered injectable therapies, in recent years we have seen research designers, largely influenced by FDA guidelines, further narrow the definition of the “injection naive” individual. Most impactful is “injection naive” defined as lifetime injection experience with any device for any duration of time.

This is routinely confirmed to include the injection of self, the injection of others, the injection of a pet, being trained to perform an injection including simulation into an injection pad. By default, anyone who participates in an injection device usability study would then be considered “injection experienced”.

Challenges in Recruitment

Given the aforementioned rise in injectable therapies coupled with the tightening of naive definitions, recruitment of injection naive participants is becoming increasingly difficult, if not impossible in the setting of certain conditions.

The US general population is an injection experienced population. While this is great news for the injection experienced quota buckets, seeking patients and caregivers who are truly injection naive is rarely a feasible avenue in the US, especially in the setting of a chronic condition.   

The Recommendations 

The most important factor is education and intervention at the design level should a device usability project include a naive segment. As, once the device research methodology is approved, it is incredibly difficult to walk it back and request flexibility and exceptions.

Below are recommendations for ensuring your research is well represented by an injection naive cohort while presenting a segment that is recruitable to your recruiting firm. Including even one of these options in the design of your naive quota qualifiers significantly increases the incidence of recruitment.

• Be Specific. Tailor your device experience to the device being tested. Autoinjectors, pre-filled syringes, injection pens, infusion and patch pumps, vial/ syringe and wearable injectors all require different techniques of administration. Experience with one does not equate to experience for all. 
• Consider the Time Lapse. A good rule of thumb is 10 years. It is reasonable to assume, especially with the forever changing injection device design, that if an individual has not administered an injection within the past 10 years, they can be considered naive.
• Be Open to Surrogates. If true, lifetime injection naivety must be a requirement, it will be imperative to open the pool. Especially in the context of a chronic condition, whether patient or caregiver, the recruit criteria will need to allow for the inclusion of proxy participants from the general population to represent the naive cohort.
• The Screener. It is important that the developed screener clearly distinguishes between injection-naive and injection-experienced individuals. One must take care to ensure the final screener is fully inclusive of all devices, injection methods and time periods as is required to qualify for the research.

We are privileged to conduct medical device usability research in the US. To maintain our progress and prevent recruitment challenges, it is essential for everyone involved in device UX to stay informed about the evolving trends in the adoption and prescription of at-home administered injectables nationwide.

This awareness should be integrated into the development of participant inclusion criteria. By doing so, we can ensure a seamless recruitment process for all parties involved: the client, the recruiting firm, and the participants.