Skip to main content

Research Repository

Advanced Search

Optimising cluster survey design for planning schistosomiasis preventive chemotherapy

Knowles, S C L; Sturrock, H J W; Turner, H; Whitton, J M; Gower, C M; Jemu, S; Phillips, A E; Meite, A; Thomas, B; Kollie, K; Thomas, C; Rebollo, M P; Styles, B; Clements, M; Fenwick, A; Harrison, W E; Fleming, F M


S C L Knowles

H J W Sturrock

H Turner

J M Whitton

C M Gower

S Jemu

A E Phillips

A Meite

B Thomas

K Kollie

C Thomas

M P Rebollo

B Styles

M Clements

A Fenwick

W E Harrison

F M Fleming


We used baseline schistosomiasis mapping surveys from three countries (Malawi, Côte d’Ivoire and Liberia) to generate spatially realistic gold standard datasets, against which we tested alternative two-stage cluster survey designs. We assessed how sampling different numbers of schools per district (2–20) and children per school (10–50) influences the accuracy of prevalence estimates and treatment class assignment, and we compared survey cost-efficiency using data from Malawi. Due to the focal nature of schistosomiasis, up to 53% simulated surveys involving 2–5 schools per district failed to detect schistosomiasis in low endemicity areas (1–10% prevalence). Increasing the number of schools surveyed per district improved treatment class assignment far more than increasing the number of children sampled per school. For Malawi, surveys of 15 schools per district and 20–30 children per school reliably detected endemic schistosomiasis and maximised cost-efficiency. In sensitivity analyses where treatment costs and the country considered were varied, optimal survey size was remarkably consistent, with cost-efficiency maximised at 15–20 schools per district.


Knowles, S. C. L., Sturrock, H. J. W., Turner, H., Whitton, J. M., Gower, C. M., Jemu, S., …Fleming, F. M. (2017). Optimising cluster survey design for planning schistosomiasis preventive chemotherapy. PLoS Neglected Tropical Diseases, 11(5),

Journal Article Type Article
Acceptance Date Apr 26, 2017
Publication Date May 26, 2017
Deposit Date Jul 19, 2017
Publicly Available Date Jul 19, 2017
Print ISSN 1935-2727
Publisher Public Library of Science
Peer Reviewed Peer Reviewed
Volume 11
Issue 5
Public URL


Downloadable Citations