Lot Quality Assurance Sampling to Monitor Supplemental Immunization Activity Quality: An Essential Tool for Improving Performance in Polio Endemic Countries

Monitoring the quality of supplementary immunization activities (SIAs) is a key tool for polio eradication.

Regular monitoring data, however, are often unreliable, showing high coverage levels in virtually all areas, including

those with ongoing virus circulation. To address this challenge, lot quality assurance sampling (LQAS)

was introduced in 2009 as an additional tool to monitor SIA quality. Now used in 8 countries, LQAS provides a

number of programmatic benefits: identifying areas of weak coverage quality with statistical reliability, differentiating

areas of varying coverage with greater precision, and allowing for trend analysis of campaign quality.

LQAS also accommodates changes to survey format, interpretation thresholds, evaluations of sample size, and

data collection through mobile phones to improve timeliness of reporting and allow for visualization of campaign

quality. LQAS becomes increasingly important to address remaining gaps in SIA quality