Re-analysis of health and educational impacts of a school-based deworming programme in western Kenya: a pure replication

Published on Oct 1, 2015in International Journal of Epidemiology7.34
· DOI :10.1093/ije/dyv127
Alexander M Aiken14
Estimated H-index: 14
Calum Davey11
Estimated H-index: 11
+ 1 AuthorsRichard J. Hayes86
Estimated H-index: 86
(Lond: University of London)
Background: Helminth (worm) infections cause morbidity among poor communities worldwide. An influential study conducted in Kenya in 1998‐99 reported that a schoolbased drug-and-educational intervention had benefits regarding worm infections and school attendance. Effects were seen among children treated with deworming drugs, untreated children in intervention schools and children in nearby non-intervention schools. Combining these effects, the intervention was reported to increase school attendance by 7.5% in treated children. Effects on other outcomes (worm infections, anaemia, nutritional status and examination performance) were also investigated. Methods: In this pure replication, we used data provided by the original authors to reanalyse the study according to their methods. We compared these results against those presented in the original paper. Results: Although most results were reproduced as originally reported, we identified discrepancies of several types between the original findings and re-analysis. For worm infections, re-analysis showed reductions similar to those originally reported. For anaemia prevalence, in contrast to the original findings, re-analysis found no evidence of benefit. For nutritional status, both original findings and re-analysis described modest evidence for a small improvement. For school attendance, re-analysis showed benefits similar to those originally found in intervention schools for both children who did and those who did not receive deworming drugs. However, after correction of coding errors, there was little evidence of an indirect effect on school attendance among children in schools close to intervention schools. Combining these effects gave a total increase in attendance of 3.9% among treated children, which was no longer statistically significant. As in the original results, re-analysis found no effect of the intervention on examination performance.
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#1Jeffrey M. Bethony (FIOCRUZ: Oswaldo Cruz Foundation)H-Index: 50
#2Simon Brooker (Lond: University of London)H-Index: 70
Last.Peter J. Hotez (GW: George Washington University)H-Index: 83
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Cited By55
#1David Taylor-Robinson (University of Liverpool)H-Index: 57
#2Nicola Maayan (Cochrane Collaboration)H-Index: 11
Last.Paul Garner (LSTM: Liverpool School of Tropical Medicine)H-Index: 51
view all 5 authors...
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