WHO has developed guidelines on systematic screening for active tuberculosis (TB) based on a thorough review of available evidence. Early detection of TB is essential to further improve health outcomes for people with TB, and to reduce TB transmission more effectively. Systematic screening in high risk groups is a possible complement to efforts to improve the patient-initiated pathway to TB diagnosis (that is, diagnosing TB among people who actively seek care with TB symptoms, also called “passive case-finding”).

The available evidence suggest that screening, if done in the right way and targeting the right people, may reduce suffering and death. However the review also highlights several reasons to be cautious. As discussed in detail in this document, there is a need to balance potential benefits against the risks and costs of screening. Some risk groups should always be screened, whereas the prioritization of other risk groups as well as the choice of screening approach depend on the epidemiology, the health-system context, and the resources available.

This document sets out basic principles for prioritizing risk groups and choosing a screening approach. It emphasizes the importance of assessing the epidemiological situation, adapting approaches to local situations, integrating TB screening into other health-promotion activities, minimizing the risk of harm to individuals, and engaging in continual monitoring and evaluation.

Contents

• Foreword
• Acknowledgements
• Executive summary
• Abbreviations
• Definitions
• 1. Purpose of guideline and target audience
  • 1.1 Purpose
  • 1.2 Target audience
• 2. Definition of screening for active TB in risk groups
  • 2.1 Systematic screening for active TB
  • 2.2 Risk groups
• 3. Rationale and objectives of screening for active TB
  • 3.1 Challenges to TB care and control
  • 3.2 Objectives and goals of screening for active TB
• 4. Guideline development process
  • 4.1 Scoping, Guideline Development Group and peer review
  • 4.2 GRADE tables and Decision tables
  • 4.3 Grading the recommendations
  • 4.4 Proposed subsidiary guideline products and implementation plan
• 5. Summaries of the systematic reviews
  • 5.1 Review 1: systematic review of the benefits of systematic screening for active TB to communities and individuals
  • 5.2 Review 2: systematic review of the sensitivity and specificity of different screening tools and algorithms
  • 5.3 Review 3: systematic review of the number needed to screen in different risk groups
  • 5.4 Review 4: systematic review of the acceptability of screening
• 6. Assessing TB screening against generic criteria for screening
• 7. Key principles for screening for active TB
• 8. Recommendations on risk groups to be screened for active TB
  • 8.1 Strong recommendations
  • 8.2 Conditional recommendations
• 9. Algorithms for screening and diagnosis
  • 9.1 Screening adults and children aged 10 years or older
  • 9.2 Screening children younger than 10 years
• 10. Monitoring and evaluation
  • 10.1 Proposed indicators
  • 10.2 Routines for recording and reporting
  • 10.3 Programmatic evaluations
  • 10.4 Monitoring time trends for reprioritization
  • 10.5 Research
• Annex I GRADE summary table: benefits of screening for tuberculosis (TB), all risk groups combined
• Annex II GRADE summary tables: sensitivity and specificity of screening tools for tuberculosis (TB)
• Annex III Flow charts of algorithms for screening and diagnosing tuberculosis (TB) in adults, with modelled yields and predictive values
• Annex IV Guideline Development Group, WHO secretariat and peer reviewers
• References
• Supporting material

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