Inclusivity intervention enters a primary care heart failure trial with cost under review
Heart failure trials have long struggled with a basic validity problem: the people enrolled often do not resemble the people seen every day in routine care. Participants tend to be younger, male, and of White ethnicity, while real-world heart failure populations include a broader mix of women and people from under-represented ethnic groups. This protocol in BMJ Open sets out a practical attempt to narrow that gap inside a pragmatic primary care randomised controlled trial, using an inclusivity intervention designed to improve participation from groups that are routinely left behind in research recruitment.
The study is not testing a drug or comparing competing cardiac devices. It is testing the machinery of trial access itself.
Recruitment bias has become a validity problem, not just a fairness problem
In heart failure research, under-representation does more than weaken diversity metrics. It can distort external validity, making trial results harder to apply to the wider population that clinicians actually treat. A study population skewed toward younger men may not fully capture how symptom burden, comorbidity, adherence, caregiving constraints, or communication barriers shape participation in older adults, women, and minority ethnic groups. The protocol addresses that problem by embedding an inclusivity intervention within an existing primary care heart failure trial rather than treating recruitment equity as an afterthought.
The intervention was designed using existing guidance on how to increase participation of under-represented groups in research. That matters because the protocol is not improvising a local solution from scratch; it is building from established recommendations and then examining whether those components work in the real constraints of a live trial. By doing so, the investigators can assess whether the intervention improves participation and whether the added effort is worth the cost.
Budget constraints shape the evaluation as much as the intervention itself
The evaluation will happen within the existing trial budget, which limits how deep and how broad the assessment can be. That constraint is central to the protocol. A lower-cost intervention may be easier to scale across future studies, but limited resources also restrict how much detail can be gathered about which individual components drive change. In practice, that means the evaluation must balance methodological rigor with feasibility, a recurring tension in implementation research.
A single sentence captures the core trade-off: this project may identify an approach that is workable, but not every moving part will be measurable in full resolution.
The team plans to evaluate both the intervention and its cost. That dual focus is important because research groups often discuss inclusivity as an ethical and scientific obligation while leaving the economic burden unmeasured. Trial teams that want to improve representativeness need to know what those gains cost in staff time, trial operations, and recruitment workflows. Without that information, promising strategies can remain too labor-intensive to adopt widely.
Women remain a persistent gap, but this intervention is not built solely around sex
The protocol is explicit about one limitation up front: the intervention is not specifically designed to improve recruitment of women. In other words, it aims to broaden participation across under-represented groups, but it does not guarantee that every subgroup will be adequately represented. Some groups may remain under-represented even if the intervention performs as intended.
That limitation is not trivial. Heart failure research has repeatedly shown that representativeness is difficult to fix with a single intervention, especially when under-representation arises from multiple causes at once: referral patterns, trial eligibility criteria, patient preferences, language barriers, transport limitations, caregiving demands, and the way research is presented in clinical settings. An inclusivity strategy can improve access, but it cannot erase structural barriers by itself.
Why pragmatic primary care is the right testing ground
Embedding the intervention in a primary care heart failure trial gives the evaluation a meaningful setting. Primary care is where many patients with heart failure are managed, and pragmatic trial designs are intended to track real-world practice rather than idealized research conditions. If an inclusivity intervention cannot function in that environment, its usefulness elsewhere becomes harder to defend. If it can, the findings may inform future studies that want to recruit more fairly without adding unsustainable complexity.
The protocol therefore serves two scientific purposes at once. First, it tests whether the intervention changes who enters the trial. Second, it examines whether the strategy is affordable enough to carry forward. Those are different questions, and both matter for trial design.
Generalizability depends on more than sample size
Clinical research often treats representativeness as a secondary concern, but in heart failure it directly affects how confidently clinicians can use trial results. Treatment effects, tolerability, adherence, and follow-up burden may all vary across patient groups that differ in age, sex, ethnicity, and social context. A trial that recruits a narrower slice of the population may still be internally valid, yet its real-world value drops if the enrolled sample fails to reflect those who will later receive care.
This protocol tackles that issue at the point where it often begins: the recruitment process. By studying inclusivity as an intervention rather than a slogan, the investigators are asking whether trial design itself can be adjusted to better reflect the populations most affected by heart failure. The answer will depend not only on participation outcomes, but on whether the intervention can be delivered inside routine trial budgets and operations.
The most immediate unresolved issue is whether the gains in participation will be large enough to justify routine use, especially when budget limits prevent a fuller analysis of which elements do the most work. A protocol can define the question well. It cannot yet tell us whether the intervention will change the composition of future heart failure trials in a durable way.