The e-prevalence survey platform responds to the growing need for monitoring of national TB program effectiveness. TB prevalence is a MDG 6 indicator that can be directly measured to review progress of implementers. Funding is available for surveys, and governments and international institutions like WHO recognize the importance of measuring impact. The e-prevalence survey platform allows all participant data to be merged in one electronic file which can be sent over any mobile phone network to a central database.

A typical survey in a TB high burden setting reaches a sample size of 50,000- 80,000 and a cluster size of 500-800. Typically 12-15 staff members are needed per field team for 6–10 months with 3-4 teams in operation. Average costs of traditional surveys are estimated at US$ 2-3 million including Capital Investment (CXR, Lab, Cars), Human Resource (salaries), Survey Operation (Field and Central), Pre & Post survey events, technical assistance. Innovations in e-prevalence to support data collection and Chest Imaging allow for significant reductions in operational cost and lead time.

Pre-conditions for e-prevalence survey

• Use proven IT technology, mobile phone network and stable PACS software
• Full electronic (from questionnaire to final report)
• Use PDA's to capture patient details, perform questionnaires and print barcode labels
• Full patient data must be retained for patient follow-up should TB be detected
• Only specific details in prevalence survey data - Age, Sex, Region, etc
• Digital Chest X-ray (DR) & PACS with quality image compression
• Participant data and digital Chest X-ray to be sent automatically via mobile phone or satellite network
• Computer Aided Detection - to be used as a second opinion on site or 3rd reading of the X-ray

e-prevalence survey process

Commonly used in high burden countries WHO/STOP TB: Strategy 3

Start

1. Participant data collected on site electronically with PDA entering automatically into the central database and printing a unique barcode
2. Questionnaire (downloading from 1) all applicable c.q. permitted personal data); selection menu for scoring and automated counting of result
3. On site make digital Chest X-ray (downloading from 1) all applicable c.q. permitted personal data, including the CRRS and related reading results on site)
4. Automatic back-up on local computer workstation and forwarding of the participant file including questionnaire and compressed CXR over 3G network to central database for data consolidation and centralised 2nd reading of the CXR
5. Fill out fields for smear microscopy and culture results if applicable End

e-prevalence survey platform

In below graph the all electronic platform for TB prevalence surveys is illustrated. This set-up has already been successfully in operation in TB screening programs of European TB programs.