Study Reveals Over-Reporting of Vaccine Coverage Data in the Democratic Republic of Congo

A mixed-method study conducted at the University of Kinshasa has found significant discrepancies between routine vaccine coverage data and surveys, with over-reporting rates exceeding 30%. The research, which investigated explanatory factors for this phenomenon, identified six key variables at the health zone level and seven at the health center level that contribute to over-reporting. These factors include pressure on managers to meet annual targets, availability of data collection tools, and the existence of designated health data collectors.

Key Takeaways:

• The study found that over-reporting of routine immunization data was a widespread issue in the Democratic Republic of Congo, with 90% of health zones and 43% of health centers surveyed experiencing discrepancies.
• Pressure on managers to achieve pre-established annual targets was the most significant factor influencing over-reporting at the health zone level (p = 0.016).
• The availability of a cell phone, existence of a table or graph for coverage monitoring, and designated health data collector were the most significant factors contributing to over-reporting at the health center level.
• The study identified three over-reporting practices: deliberate inflation of vaccine delivery figures, readjustment of expected target population figures, and occasional errors in data transcription.
• The research concluded that over-reporting is essentially generated by providers and can be addressed by lifting pressure on managers, improving data management, and qualifying staff responsible for immunization data.

Statistics:

• 30% or more difference between routine vaccine coverage surveys and routine vaccine coverage data.
• 90% of health zones (77 out of 86) and 43% of health centers surveyed experienced over-reporting.
• 6 key variables at the health zone level: pressure on managers to meet annual targets (p = 0.016), availability of data collection tools (p = 0.010), bearer message for manual transport of reports (p = 0.031), etc.
• 7 key variables at the health center level: availability of a cell phone (p = 0.002), existence of table or graph for coverage monitoring (p = 0.003), etc.
• 117 health centers, 30 health zone offices, and 13 provincial health offices participated in the study.

Sources:

• Reasons for over-reporting of routine immunization administrative data in the Democratic Republic of Congo: a mixed cross-sectional study to determine explanatory factors for poor data quality. BMC Public Health, 2025,25(1):1-15. (BMC Public Health - http://bmcpublichealth.biomedcentral.com).
• University of Kinshasa Researchers Have Published New Study Findings on Vaccines (Reasons for over-reporting of routine immunization administrative data in the Democratic Republic of Congo: a mixed cross-sectional study to determine explanatory ...). Health Insurance Law Weekly. October 26, 2025; p 473.