Evidence gap analysis is a structured process used to identify missing or incomplete evidence before a health technology assessment, reimbursement submission or market access strategy.
In the context of HTA, evidence gap analysis helps determine whether the available data are strong enough to support the value of a medicine, medical device, diagnostic test, digital health solution or healthcare intervention.
The process compares the existing evidence package with the expectations of decision-makers, payers, reimbursement bodies and HTA agencies.
It does not only ask whether evidence exists. It asks whether the evidence is relevant, complete, robust and aligned with the local decision context.
In simple terms, evidence gap analysis helps answer an important question:
What evidence is missing to support a strong HTA and market access strategy?
Why is evidence gap analysis important?
Evidence gaps can create uncertainty during HTA and reimbursement decisions. A technology may have promising clinical data, but still face challenges if important evidence is missing.
For example, there may be limited comparative evidence against the current standard of care. There may be uncertainty around long-term outcomes, local epidemiology, treatment pathways, quality of life, costs or budget impact.
These gaps can affect how decision-makers interpret the value of a technology.
Evidence gap analysis helps identify these issues early, before they become barriers during submission or reimbursement discussions. It allows organisations to understand where the evidence package is strong, where it is limited and what additional work may be needed.
For healthcare companies, this process can reduce risk and improve strategic planning before engaging with HTA agencies or payers.
How does evidence gap analysis support market access?
Market access depends on the ability to demonstrate value clearly and convincingly. This requires more than clinical trial results.
Decision-makers often need evidence on comparative effectiveness, safety, cost-effectiveness, budget impact, patient outcomes and real-world use. If these areas are not sufficiently addressed, access may be delayed, restricted or challenged.
Evidence gap analysis supports market access by identifying what information is needed to build a stronger value story.
For example, it can help determine whether additional evidence synthesis is required, whether an indirect treatment comparison is needed, whether real-world evidence should be generated or whether an economic model needs to be adapted to a local context.
It also helps prioritise actions. Not every evidence gap has the same impact. Some gaps may be critical for reimbursement, while others may be less important. A structured analysis helps focus resources on the areas that matter most.
What types of evidence gaps can exist?
Evidence gaps can appear across different areas of an HTA or reimbursement strategy.
Clinical evidence gaps may include limited head-to-head data, uncertainty around comparative effectiveness, lack of subgroup analysis or insufficient long-term safety data.
Economic evidence gaps may relate to cost-effectiveness, budget impact, utility values, resource use or model assumptions.
Local evidence gaps may include limited data on epidemiology, treatment pathways, current standard of care or healthcare costs in a specific country.
Real-world evidence gaps may involve uncertainty about how a technology performs outside controlled clinical trials, including adherence, persistence, patient characteristics and healthcare resource utilisation.
Patient evidence gaps may include limited information on quality of life, patient preferences, symptoms, functioning or treatment experience.
The goal is not only to list these gaps, but to understand how each one may influence decision-making.
When should evidence gap analysis be performed?
Evidence gap analysis should ideally be performed early in the market access and HTA planning process.
It can be useful during early product development, pre-launch planning, clinical development strategy, reimbursement preparation and local adaptation of global value materials.
When performed early, it gives organisations time to generate additional evidence, adapt economic models, refine value messages and prepare stronger submissions.
If evidence gap analysis is performed too late, there may be limited time to address important weaknesses before submission.
For this reason, it should be seen as a strategic planning tool, not only as a technical checklist.
Final thoughts
Evidence gap analysis plays an important role in HTA, reimbursement and market access. It helps organisations understand whether the available evidence is sufficient, where uncertainty remains and what actions are needed to strengthen the value story.
By identifying evidence gaps early, companies can prepare more robust submissions, anticipate payer questions and improve the alignment between evidence generation and decision-maker expectations.
At Clevidence, we support organisations with evidence gap analysis, HTA strategy, value dossiers, reimbursement submissions, evidence synthesis, real-world evidence planning and local adaptation.