3. Processes and methods
1. Processes and methods
HTA practices vary in scope, methodology, and level of detail. However, the process generally follows three key phases:
- Assessment
- Appraisal
- Decision-making & Implementation
ℹ️ Click on the Information buttons on the figure below to learn more about the three key phases
Processes followed by HTA bodies
HTA bodies determine what information decision-makers need about a technology and how to gather it.
Most assessments involve the following steps, though not all HTA bodies follow every step or in a strict order:
Define which technologies to assess.
Clarify the assessment problems.
Search for existing data.
Gather original data if needed.
Judge the strength of the evidence.
Combine findings from sources.
Draw conclusions and advise.
Disseminate findings widely.
Evaluate the real-world effects.
For example, while clinical effectiveness is crucial, some technologies may also raise ethical concerns. An HTA body must decide whether to apply a standard assessment process to all technologies or adapt it case by case. Should ethical evaluations always be included, or only when relevant?
Methods used in HTA for evidence collection
To be able to retrieve/collect, interpret, and integrate evidence before completing an assessment, HTA bodies use different approaches, primarily:
- Primary data collection – Gathering original data from clinical trials or observational studies.
- Secondary (integrative) methods – Synthesising existing data from systematic reviews, meta-analyses, data reported in journal articles or from epidemiological or administrative data sets, including from primary data studies.
Economic analysis methods can involve one or both. Most HTA bodies rely on integrative methods to analyse and interpret available primary data, distinguishing stronger from weaker evidence. Some assessments involve multiple cycles of retrieving, interpreting, and synthesising evidence.
Challenges in evidence collection
Assessments cannot always rely on the most rigorous studies. Real-world data becomes available only after a medicine is on the market, meaning policies often must be made before definitive studies are completed. Given their varying assessment orientations, resource constraints and other factors, HTA bodies tend to rely on a combination of different methods.
Despite the variety of assessment approaches, evidence addressing the following issues is usually required by the HTA body in order to assess a technology:
- Disease burden and projected epidemiological trends
- Projected epidemiological trends of a disease
- Relative effectiveness of the technology
- Cost-effectiveness (though some HTA bodies focus more on added clinical benefit or budget impact)
- How patients value the outcomes of therapy.
HTA bodies may gather this evidence themselves, commission new research, or request data from the marketing authorisation holder (MAH) of a medicine.