Reliability of information recorded on the National Immunization Program Information System

Area of Science:

• Public Health
• Epidemiology
• Health Information Systems

Background:

• The National Immunization Program Information System (SI-PNI) is vital for monitoring vaccination coverage in Brazil.
• Assessing the accuracy of SI-PNI data against vaccination cards is essential for reliable public health surveillance.
• Previous studies have indicated potential data quality issues in immunization registries.

Purpose of the Study:

• To evaluate the reliability of vaccination records in the SI-PNI by comparing them with vaccination cards.
• To analyze the agreement and discrepancies in recorded doses and dates between the SI-PNI and vaccination cards.
• To identify the extent of underrecording of children and vaccination events within the SI-PNI.

Main Methods:

• A subsample of 4,050 children with complete vaccination schedules at 24 months was selected from a national survey.
• Data on vaccination doses and dates were compared between the SI-PNI and individual vaccination cards.
• Statistical analysis was performed to determine the agreement rate and identify discrepancies between the two data sources.

Main Results:

• Of the 4,050 children studied, 11% were not recorded in the SI-PNI.
• 32% of children had unrecorded vaccination doses or dates in the SI-PNI.
• Overall agreement between vaccination cards and SI-PNI records was 86%, with significant variation when individual doses were analyzed.

Conclusions:

• While overall agreement is high, underrecording of children and vaccination events in the SI-PNI is a concern.
• Discrepancies in data can lead to inaccurate estimates of childhood vaccination coverage.
• Improving data quality and addressing underrecording in the SI-PNI is critical for effective immunization program monitoring.