Efforts to improve tuberculosis diagnosis could receive a boost following new World Health Organization guidance aimed at addressing weaknesses in research used to evaluate emerging diagnostic technologies.
The guidance, published on October 21, seeks to improve how researchers generate and report evidence on new tuberculosis (TB) diagnostic tests, including their accuracy, affordability, accessibility and suitability for different patient populations.
The move follows concerns that studies evaluating new TB diagnostics have often provided incomplete evidence, overlooked vulnerable populations and focused heavily on test accuracy without adequately examining whether the technologies are practical, affordable or acceptable to the people who need them.
These shortcomings can make it difficult for health authorities to determine which diagnostic technologies should be recommended for wider use.
WHO’s new document, Guidance on Evidence Generation for New Tuberculosis Diagnostics, provides researchers, developers, funders and other stakeholders with a framework for producing stronger evidence to inform the organisation’s future recommendations.
“Robust evidence is the foundation of strong WHO recommendations,” said Tereza Kasaeva, Director of WHO’s Department for HIV, Tuberculosis, Hepatitis and Sexually Transmitted Infections.
She said the guidance provides a roadmap for generating the evidence needed to help better diagnostic technologies reach more people.
Beyond whether a test works
One of the central issues addressed by the guidance is the difference between establishing whether a diagnostic test can accurately detect a disease and determining whether it can improve healthcare in practice.
Diagnostic accuracy remains essential, but WHO says studies also need to examine factors such as cost-effectiveness, equity, acceptability and feasibility.
A test may perform well under controlled research conditions but face challenges when introduced into health facilities with limited resources, staffing or diagnostic infrastructure.
Similarly, research that excludes vulnerable populations may fail to establish whether a new technology performs adequately among the people who could benefit most from improved diagnosis.
WHO’s guidance therefore outlines methodological approaches for designing diagnostic accuracy studies, selecting participants, determining sample sizes and reporting results.
It also emphasises the need to generate evidence on outcomes that matter to patients, alongside considerations affecting the practical delivery of testing services.
By addressing these gaps, the organisation aims to make research findings more useful when assessing new technologies and developing recommendations for countries.
A new framework for diagnostic research
The guidance introduces an analytical framework that maps the role of a diagnostic test across the clinical pathway.
This approach links the purpose of a test to decisions about study design, the populations involved, research methods and the reporting of results.
The objective is to help researchers design studies that provide evidence relevant to clinical decisions and public health policy, rather than producing findings that are difficult to apply beyond the research setting.
WHO said study results have often been reported inconsistently, making it difficult to combine findings from different investigations and assess the overall strength of the evidence.
The organisation argues that these challenges can be addressed through better research methods and clearer reporting standards.
The new guidance is the third in WHO’s series on evidence generation, following earlier documents addressing new TB treatment regimens and preventive treatment.
Together, the publications seek to strengthen the evidence used to guide decisions across different aspects of tuberculosis prevention, diagnosis and treatment.
Turning research into accessible healthcare
The publication also highlights the wider challenge of translating scientific advances into healthcare policies and practices that benefit patients.
Developing a promising diagnostic technology does not automatically mean it will be recommended for use or adopted by health systems.
Decision-makers need evidence that helps them assess its performance, potential benefits, costs and suitability for the settings where it would be used.
WHO’s new guidance is intended to strengthen this process by helping researchers generate evidence that can support robust recommendations and faster adoption of suitable diagnostic technologies.
It complements WHO’s existing target product profiles for tuberculosis diagnosis and detection of drug resistance, which outline desired characteristics for diagnostic products.
However, the guidance itself does not introduce a new diagnostic test or establish that any particular technology is ready for wider use.
Instead, it seeks to improve the quality and relevance of the research that informs such decisions.
For countries dealing with the burden of tuberculosis, the long-term significance will depend on whether stronger evidence helps health authorities identify appropriate diagnostic tools and translate recommendations into accessible testing services.
The initiative ultimately addresses a fundamental question in medical innovation: how can promising technologies move from research into routine healthcare without compromising scientific standards or overlooking the needs of vulnerable patients?
