CAD4TB triage of 94,694 people in Nigeria yields 2,337 TB cases

KNCV/USAID deployment Jan–Sep 2022: CAD4TB v7 screened 94,694 people in eight Nigerian states; 2,337 TB cases diagnosed, 97% treated

AI system

System

CAD4TB computer-aided detection on ultra-portable digital chest X-ray

Model

Not assessed

Release

CAD4TB version 7.

Application developer

Delft Imaging

Role

CAD4TB scored chest X-rays for signs of tuberculosis.

Configuration

The deployment used CAD4TB version 7 with a threshold score of 50.

Inputs and outputs

Not assessed

Autonomy

Not assessed

Workflow

Ultra-portable X-ray units with CAD4TB v7 at threshold 50. Community mobilization and same-day Xpert testing. USAID funding through the iNTP project.

Human oversight

Not assessed

Relation to AI

A parallel algorithm classified anyone positive on symptom screening or with a CAD4TB score of 50 or above as presumptive TB. They went for Xpert testing and/or clinical assessment, so the AI score was one of two gates to testing, not the sole gate. Of the 2,337 diagnosed, 1,614 (69.1%) scored 50 or above and 723 (30.9%) scored below 50. The TB yield also depends on X-ray reach, Xpert availability and treatment linkage. Both papers are authored by implementing organizations (KNCV Nigeria, IHVN, USAID, NTBLCP), not the vendor.

AI contribution

A parallel algorithm classified anyone positive on symptom screening or with a CAD4TB score of 50 or above as presumptive TB. They went for Xpert testing and/or clinical assessment, so the AI score was one of two gates to testing, not the sole gate. Of the 2,337 diagnosed, 1,614 (69.1%) scored 50 or above and 723 (30.9%) scored below 50. The TB yield also depends on X-ray reach, Xpert availability and treatment linkage. Both papers are authored by implementing organizations (KNCV Nigeria, IHVN, USAID, NTBLCP), not the vendor.

Benefits

Outcome identifiers

Not assessed

Benefit

2,337 TB cases diagnosed, 97% treated

Category

Improved Physical Health

Status

Not assessed

Beneficiary groups

People. Organizations. Society.

Beneficiaries

Not assessed

Reach

Not assessed

Distribution and access

Not assessed

Duration

Not assessed

Expected?

Yes

Costs and harms

Not assessed

Measurement

Studies

Not assessed

Study design

Not assessed

Measurement

Not assessed

Setting and sample

Not assessed

Measures

2,337 TB cases diagnosed, 97% treated

Comparison

KNCV Nigeria's other 2022 case-finding strategies in the same states without portable X-ray (intensified case finding in public and private facilities, medicine vendors and community pharmacists, contact investigation, community active case finding)

Results

Reference: NNS 205.6 (public facilities), 179.0 (private facilities), 127.8 (medicine vendors and community pharmacists), 49.0 (contact investigation), 388.5 (community active case-finding). Result: NNS 44.9 with PDX-CAD.

Additional value from AI

Not assessed

Limitations

Not assessed

Denominators

Not assessed

Materials for replication

Not assessed

Money

Kind of value

Not assessed

Amount

Not assessed

Currency and prices

Not assessed

Period and unit

Not assessed

Realization

Not assessed

Recipients and payers

Not assessed

Gross or net

Not assessed

Included costs

Not assessed

Comparison

Not assessed

Method

Not assessed

Return and payback

Not assessed

People and places

Participants

Developer: Delft Imaging. Operator: KNCV Tuberculosis Foundation Nigeria and Institute of Human Virology Nigeria with the National TB and Leprosy Control Program, funded by USAID.

Jurisdictions

Benefit: Eight states, Nigeria. Developer: Netherlands. Operator: Nigeria.

Ownership and control

Not assessed

Dependencies

Not assessed

Cross-border connections

Not assessed

Geopolitical implications

Not assessed

Follow-up

Conditions for replication

Threshold calibrated to local prevalence. Xpert cartridge supply and sample transport. Treatment linkage within days.

Replication attempts

2 follow-up entries. Benefit recurred: 1. Outcome unresolved: 1.

Later findings

30 September 2025. KNCV Nigeria's 2025 annual report says the IMPACT project completed deployment of 390 portable digital X-ray units with AI across all 36 states and the FCT, adding 266 units in 2025, and screened over 780,000 people with over 23,000 TB cases diagnosed in January to September 2025.

Availability

Not assessed

Institutional decision

Not assessed

Grounds

Not assessed

Action and result

Not assessed

Success criterion

Not assessed

Evidence

Source numbers

AIBD-0096-source-0001–0003

Citations

Numbered references below.

Language

Not assessed

Source relationships

Operator

Original evidence

Not assessed

Access and versions

Not assessed

Supported findings

Not assessed

Evidence strength

Not assessed

Missing evidence

Not assessed

Grades

Assessed benefits

People. Organizations. Society.

Depth

Not assessed

Reasons

People: Aggregate screening yield; the sources do not document any individual's outcome attributable to the software. Organizations: Efficiency figures (NNS 38, NNT 4) are program aggregates without a discrete attributable event. Society: 2,337 diagnoses are an aggregate program result.

Observed or intended

Not assessed

Rubric

Not assessed

Assessor and date

Not assessed

Alternative assessments

Not assessed

Fill

The deployer's account

Entry details

Kind

Not assessed

Field

Global health: tuberculosis case finding. Public health program.

Purpose

Triage chest X-rays to select presumptive TB cases for molecular testing during community active case finding.

Dates

Date basis unassessed: 2022 (precision unassessed). Updated: 21 October 2026.

Stage

Not assessed

Version

SHA-256: ceffb7ad68c5…

References

Other identifiers

AI Incident Database: 81.

Category mappings

Not assessed

Brief

Not assessed

Revisions

7 revisions. Latest: 21 October 2026.

Sources

  1. Peer-reviewed study Deployer

    Alege, A., Useni, S., Ihesie, A., Eneogu, R., Agbaje, A., et al. (2025). Impact of the use of the ultra-portable digital x-ray with CAD4TB for active case finding for tuberculosis in Nigeria. Frontiers in Digital Health.

  2. Peer-reviewed study Deployer

    Useni, S., Odume, B., Tukur, M., et al. (2025). Comparative analysis of the impact of portable digital X-ray on TB screening in hard-to-reach areas in Nigeria. Public Health Action 15(1), 17–20.

  3. Report Deployer

    KNCV Nigeria (2026). 2025 Annual Report. Knowledge Network for disease Control and Vigilance, Abuja (PDF posted March 2026; day not given, first day of month used).