Imperial College London
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DrKeithFraser

Faculty of Medicine, School of Public Health

Research Associate
 
 
 
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Contact

 

keith.fraser Website

 
 
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Location

 

School of Public HealthWhite City Campus

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Summary

 

Publications

Citation

BibTex format

@article{Mwandigha:2022:ije/dyz277,
author = {Mwandigha, LM and Fraser, KJ and Racine, A and Mouksassi, S and Ghani, AC},
doi = {ije/dyz277},
journal = {International Journal of Epidemiology},
pages = {954--962},
title = {Power calculations for cluster randomised trials (CRTs) with truncated Poisson-distributed outcomes: a motivating example from a malaria vector control trial},
url = {http://dx.doi.org/10.1093/ije/dyz277},
volume = {49},
year = {2022}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Background:Cluster randomized trials (CRTs) are increasingly used to study the efficacy of interventions targeted at the population level. Formulae exist to calculate sample sizes for CRTs, but they assume that the domain of the outcomes being considered covers the full range of values of the considered distribution. This assumption is frequently incorrect in epidemiological trials in which counts of infection episodes are right-truncated due to practical constraints on the number of times a person can be tested.Methods:Motivated by a malaria vector control trial with right-truncated Poisson-distributed outcomes, we investigated the effect of right-truncation on power using Monte Carlo simulations.Results:The results demonstrate that the adverse impact of right-truncation is directly proportional to the magnitude of the event rate, λ, with calculations of power being overestimated in instances where right-truncation was not accounted for. The severity of the adverse impact of right-truncation on power was more pronounced when the number of clusters was ≤30 but decreased the further the right-truncation point was from zero.Conclusions:Potential right-truncation should always be accounted for in the calculation of sample size requirements at the study design stage.
AU  - Mwandigha,LM
AU  - Fraser,KJ
AU  - Racine,A
AU  - Mouksassi,S
AU  - Ghani,AC
DO  - ije/dyz277
EP  - 962
PY  - 2022///
SN  - 0300-5771
SP  - 954
TI  - Power calculations for cluster randomised trials (CRTs) with truncated Poisson-distributed outcomes: a motivating example from a malaria vector control trial
T2  - International Journal of Epidemiology
UR  - http://dx.doi.org/10.1093/ije/dyz277
UR  - http://hdl.handle.net/10044/1/100446
VL  - 49
ER  -
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