Assessing the variability in experimental hut trials evaluating insecticide-treated nets against malaria vectors
Experimental hut trials (EHTs) are used to evaluate indoor vector control interventions against malaria vectors in a controlled setting. The level of variability present in the assay will influence whether a given study is well powered to answer the research question being considered. We utilised di...
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| Format: | Article |
| Language: | English |
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Elsevier
2023-01-01
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| Series: | Current Research in Parasitology and Vector-Borne Diseases |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2667114X23000031 |
| _version_ | 1797796338919800832 |
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| author | Joseph D. Challenger Rebecca K. Nash Corine Ngufor Antoine Sanou K. Hyacinthe Toé Sarah Moore Patrick K. Tungu Mark Rowland Geraldine M. Foster Raphael N’Guessan Ellie Sherrard-Smith Thomas S. Churcher |
| author_facet | Joseph D. Challenger Rebecca K. Nash Corine Ngufor Antoine Sanou K. Hyacinthe Toé Sarah Moore Patrick K. Tungu Mark Rowland Geraldine M. Foster Raphael N’Guessan Ellie Sherrard-Smith Thomas S. Churcher |
| author_sort | Joseph D. Challenger |
| collection | DOAJ |
| description | Experimental hut trials (EHTs) are used to evaluate indoor vector control interventions against malaria vectors in a controlled setting. The level of variability present in the assay will influence whether a given study is well powered to answer the research question being considered. We utilised disaggregated data from 15 previous EHTs to gain insight into the behaviour typically observed. Using simulations from generalised linear mixed models to obtain power estimates for EHTs, we show how factors such as the number of mosquitoes entering the huts each night and the magnitude of included random effects can influence study power. A wide variation in behaviour is observed in both the mean number of mosquitoes collected per hut per night (ranging from 1.6 to 32.5) and overdispersion in mosquito mortality. This variability in mortality is substantially greater than would be expected by chance and should be included in all statistical analyses to prevent false precision of results. We utilise both superiority and non-inferiority trials to illustrate our methodology, using mosquito mortality as the outcome of interest. The framework allows the measurement error of the assay to be reliably assessed and enables the identification of outlier results which could warrant further investigation. EHTs are increasingly playing an important role in the evaluation and regulation of indoor vector control interventions so it is important to ensure that these studies are adequately powered. |
| first_indexed | 2024-03-13T03:31:34Z |
| format | Article |
| id | doaj.art-9ff18521794b45e782e4ccf242ae4810 |
| institution | Directory Open Access Journal |
| issn | 2667-114X |
| language | English |
| last_indexed | 2024-03-13T03:31:34Z |
| publishDate | 2023-01-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Current Research in Parasitology and Vector-Borne Diseases |
| spelling | doaj.art-9ff18521794b45e782e4ccf242ae48102023-06-24T05:19:55ZengElsevierCurrent Research in Parasitology and Vector-Borne Diseases2667-114X2023-01-013100115Assessing the variability in experimental hut trials evaluating insecticide-treated nets against malaria vectorsJoseph D. Challenger0Rebecca K. Nash1Corine Ngufor2Antoine Sanou3K. Hyacinthe Toé4Sarah Moore5Patrick K. Tungu6Mark Rowland7Geraldine M. Foster8Raphael N’Guessan9Ellie Sherrard-Smith10Thomas S. Churcher11Medical Research Council Centre for Global Infections Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, UK; Corresponding author.Medical Research Council Centre for Global Infections Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, UKCentre de Recherches Entomologiques de Cotonou, Cotonou, Benin; London School of Hygiene and Tropical Medicine, London, UKCentre National de Recherche et de Formation sur le Paludisme, Burkina FasoCentre National de Recherche et de Formation sur le Paludisme, Burkina FasoVector Control Product Testing Unit (VCPTU) Ifakara Health Institute, Environmental Health, and Ecological Sciences, Bagamoyo, Tanzania; Vector Biology Unit, Department of Epidemiology and Public Health, Swiss Tropical & Public Health Institute, Basel, Switzerland; Faculty of Science, University of Basel, Basel, Switzerland; The Nelson Mandela African Institution of Science and Technology (NM-AIST), Tengeru, Arusha, TanzaniaNational Institute for Medical Research, Amani Medical Research Centre, Muheza, TanzaniaLondon School of Hygiene and Tropical Medicine, London, UKVector Biology Department, Liverpool School of Tropical Medicine, Liverpool, UKLondon School of Hygiene and Tropical Medicine, London, UK; Institut Pierre Richet, Bouaké, Republic of Côte d’IvoireMedical Research Council Centre for Global Infections Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, UKMedical Research Council Centre for Global Infections Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, UKExperimental hut trials (EHTs) are used to evaluate indoor vector control interventions against malaria vectors in a controlled setting. The level of variability present in the assay will influence whether a given study is well powered to answer the research question being considered. We utilised disaggregated data from 15 previous EHTs to gain insight into the behaviour typically observed. Using simulations from generalised linear mixed models to obtain power estimates for EHTs, we show how factors such as the number of mosquitoes entering the huts each night and the magnitude of included random effects can influence study power. A wide variation in behaviour is observed in both the mean number of mosquitoes collected per hut per night (ranging from 1.6 to 32.5) and overdispersion in mosquito mortality. This variability in mortality is substantially greater than would be expected by chance and should be included in all statistical analyses to prevent false precision of results. We utilise both superiority and non-inferiority trials to illustrate our methodology, using mosquito mortality as the outcome of interest. The framework allows the measurement error of the assay to be reliably assessed and enables the identification of outlier results which could warrant further investigation. EHTs are increasingly playing an important role in the evaluation and regulation of indoor vector control interventions so it is important to ensure that these studies are adequately powered.http://www.sciencedirect.com/science/article/pii/S2667114X23000031Experimental hut trialsInsecticide-treated netsLong-lasting insecticidal netsVector controlAnophelesPower analysis |
| spellingShingle | Joseph D. Challenger Rebecca K. Nash Corine Ngufor Antoine Sanou K. Hyacinthe Toé Sarah Moore Patrick K. Tungu Mark Rowland Geraldine M. Foster Raphael N’Guessan Ellie Sherrard-Smith Thomas S. Churcher Assessing the variability in experimental hut trials evaluating insecticide-treated nets against malaria vectors Current Research in Parasitology and Vector-Borne Diseases Experimental hut trials Insecticide-treated nets Long-lasting insecticidal nets Vector control Anopheles Power analysis |
| title | Assessing the variability in experimental hut trials evaluating insecticide-treated nets against malaria vectors |
| title_full | Assessing the variability in experimental hut trials evaluating insecticide-treated nets against malaria vectors |
| title_fullStr | Assessing the variability in experimental hut trials evaluating insecticide-treated nets against malaria vectors |
| title_full_unstemmed | Assessing the variability in experimental hut trials evaluating insecticide-treated nets against malaria vectors |
| title_short | Assessing the variability in experimental hut trials evaluating insecticide-treated nets against malaria vectors |
| title_sort | assessing the variability in experimental hut trials evaluating insecticide treated nets against malaria vectors |
| topic | Experimental hut trials Insecticide-treated nets Long-lasting insecticidal nets Vector control Anopheles Power analysis |
| url | http://www.sciencedirect.com/science/article/pii/S2667114X23000031 |
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