Validation of Vitamin A Supplementation Coverage Using Post-event Coverage Surveys in 11 Sub-Saharan African Countries
Heather Katcher *
Helen Keller International ESCA, Nairobi, Kenya.
Leigh Jaschke
Helen Keller International ESCA, Nairobi, Kenya.
Geoffrey Oruru
Helen Keller International ESCA, Nairobi, Kenya.
Jennifer Nielsen
Helen Keller International HQ, New York, NY, USA.
Jessica Blankenship
Helen Keller International ESCA, Nairobi, Kenya.
*Author to whom correspondence should be addressed.
Abstract
Objectives: Twice-yearly child health days (CHDs) have had remarkable success reaching children twice-yearly with life-saving interventions, including vitamin A supplementation (VAS). In 2012, over 80% of targeted children in Sub-Saharan Africa received VAS according to tally-sheet data. All countries implementing CHDs use tally-sheet data to measure coverage; however, coverage measured from tally-sheets is prone to errors due to inaccurate census data, incorrect tallying and mathematical errors totaling coverage across districts and regions.
Methods: To validate coverage reported by tally-sheets, Helen Keller International implemented Post-Event Coverage Surveys (PECS) using a 30x30 cluster design and standard WHO EPI cluster sampling methodology in 11 countries in sub-Saharan Africa. For each survey, 900 caretakers of children 6-59 months were interviewed within six weeks of CHDs to reduce recall bias.
Results: Thirty-five post event coverage surveys were conducted between January 2010 and July 2013. PECS coverage was lower than administrative coverage in 33/35 (94%) of cases. PECS and administrative coverage data were within a 5% margin of difference in 5 cases (14%), and within >5-10% in 8 cases (23%). However, in 11 cases (31%), results differed by >10-20%, and in 11 cases (31%), results differed by 21-82%.
Conclusions: PEC surveys indicate considerable over-reporting of coverage by tally-sheets and provide critical data that is essential to evaluate and improve VAS distribution during CHDs. The continued use of PEC surveys is recommended in areas where tally-sheet data has not been confirmed or has been shown to be unreliable.