Relative Risk Estimates from Spatial and Space-time Scan Statistics: Are They Biased?

Overview

Journal Stat Med

Publisher Wiley

Specialty Public Health

Date 2014 Mar 19

PMID 24639031

Citations 19

Authors

Marcos O Prates

Martin Kulldorff

Renato M Assuncao

Affiliations

Soon will be listed here.

Abstract

The purely spatial and space-time scan statistics have been successfully used by many scientists to detect and evaluate geographical disease clusters. Although the scan statistic has high power in correctly identifying a cluster, no study has considered the estimates of the cluster relative risk in the detected cluster. In this paper, we evaluate whether there is any bias on these estimated relative risks. Intuitively, one may expect that the estimated relative risks has upward bias, because the scan statistic cherry picks high rate areas to include in the cluster. We show that this intuition is correct for clusters with low statistical power, but with medium to high power, the bias becomes negligible. The same behavior is not observed for the prospective space-time scan statistic, where there is an increasing conservative downward bias of the relative risk as the power to detect the cluster increases.

Citing Articles

Geographic inequalities and factors associated with unfavorable outcomes in diabetes-tuberculosis and diabetes-covid comorbidities in Brazil.

Alves L, Berra T, Alves Y, Ferezin L, Vinci A, Tavares R Sci Rep. 2025; 15(1):8353.

PMID: 40069306 PMC: 11897301. DOI: 10.1038/s41598-025-93476-6.

Comparative evaluation of spatiotemporal methods for effective dengue cluster detection with a case study of national surveillance data in Thailand.

Rotejanaprasert C, Chinpong K, Lawson A, Maude R Sci Rep. 2024; 14(1):31064.

PMID: 39730684 PMC: 11680836. DOI: 10.1038/s41598-024-82212-1.

Long-Term Effect of Temperature Increase on Liver Cancer in Australia: A Bayesian Spatial Analysis.

Gan T, Bambrick H, Li Y, Ebi K, Hu W Environ Health Perspect. 2024; 132(9):97007.

PMID: 39269729 PMC: 11398296. DOI: 10.1289/EHP14574.

Spatial patterns and sociodemographic predictors of chronic obstructive pulmonary disease in Florida.

Howard S, Odoi A PeerJ. 2024; 12:e17771.

PMID: 39104363 PMC: 11299531. DOI: 10.7717/peerj.17771.

Geographic disparities in COVID-19 testing and outcomes in Florida.

Khan M, Odoi A, Odoi E BMC Public Health. 2023; 23(1):79.

PMID: 36631768 PMC: 9832260. DOI: 10.1186/s12889-022-14450-9.

References

Assuncao R, Costa M, Tavares A, Ferreira S . Fast detection of arbitrarily shaped disease clusters. Stat Med. 2006; 25(5):723-42. DOI: 10.1002/sim.2411. View

Chaput E, Meek J, Heimer R . Spatial analysis of human granulocytic ehrlichiosis near Lyme, Connecticut. Emerg Infect Dis. 2002; 8(9):943-8. PMC: 2732548. DOI: 10.3201/eid0809.020103. View

Norstrom M, Pfeiffer D, Jarp J . A space-time cluster investigation of an outbreak of acute respiratory disease in Norwegian cattle herds. Prev Vet Med. 2000; 47(1-2):107-19. DOI: 10.1016/s0167-5877(00)00159-8. View

Hjalmars U, Kulldorff M, Gustafsson G, Nagarwalla N . Childhood leukaemia in Sweden: using GIS and a spatial scan statistic for cluster detection. Stat Med. 1996; 15(7-9):707-15. DOI: 10.1002/(sici)1097-0258(19960415)15:7/9<707::aid-sim242>3.0.co;2-4. View

Thomas A, Carlin B . Late detection of breast and colorectal cancer in Minnesota counties: an application of spatial smoothing and clustering. Stat Med. 2002; 22(1):113-27. DOI: 10.1002/sim.1215. View

Sheehan T, DeChello L . A space-time analysis of the proportion of late stage breast cancer in Massachusetts, 1988 to 1997. Int J Health Geogr. 2005; 4:15. PMC: 1180846. DOI: 10.1186/1476-072X-4-15. View

Odoi A, Martin S, Michel P, Middleton D, Holt J, Wilson J . Investigation of clusters of giardiasis using GIS and a spatial scan statistic. Int J Health Geogr. 2004; 3(1):11. PMC: 436063. DOI: 10.1186/1476-072X-3-11. View

Jung I, Kulldorff M, Klassen A . A spatial scan statistic for ordinal data. Stat Med. 2006; 26(7):1594-607. DOI: 10.1002/sim.2607. View

Wylie J, Cabral T, Jolly A . Identification of networks of sexually transmitted infection: a molecular, geographic, and social network analysis. J Infect Dis. 2005; 191(6):899-906. DOI: 10.1086/427661. View

10.

Nkhoma E, Hsu C, Hunt V, Harris A . Detecting spatiotemporal clusters of accidental poisoning mortality among Texas counties, U.S., 1980 - 2001. Int J Health Geogr. 2004; 3(1):25. PMC: 529305. DOI: 10.1186/1476-072X-3-25. View

11.

Heres L, Brus D, Hagenaars T . Spatial analysis of BSE cases in the Netherlands. BMC Vet Res. 2008; 4:21. PMC: 2441619. DOI: 10.1186/1746-6148-4-21. View

12.

Kulldorff M, Heffernan R, Hartman J, Assuncao R, Mostashari F . A space-time permutation scan statistic for disease outbreak detection. PLoS Med. 2005; 2(3):e59. PMC: 548793. DOI: 10.1371/journal.pmed.0020059. View

13.

Turnbull B, Iwano E, Burnett W, Howe H, Clark L . Monitoring for clusters of disease: application to leukemia incidence in upstate New York. Am J Epidemiol. 1990; 132(1 Suppl):S136-43. DOI: 10.1093/oxfordjournals.aje.a115775. View

14.

Minamisava R, Nouer S, Neto O, Melo L, Andrade A . Spatial clusters of violent deaths in a newly urbanized region of Brazil: highlighting the social disparities. Int J Health Geogr. 2009; 8:66. PMC: 2790449. DOI: 10.1186/1476-072X-8-66. View

15.

Reperant L, Deplazes P . Cluster of Capillaria hepatica infections in non-commensal rodents from the canton of Geneva, Switzerland. Parasitol Res. 2005; 96(5):340-2. DOI: 10.1007/s00436-005-1358-y. View

16.

Jung I, Kulldorff M, Richard O . A spatial scan statistic for multinomial data. Stat Med. 2010; 29(18):1910-8. PMC: 4147837. DOI: 10.1002/sim.3951. View

17.

Kulldorff M, Athas W, Feurer E, Miller B, Key C . Evaluating cluster alarms: a space-time scan statistic and brain cancer in Los Alamos, New Mexico. Am J Public Health. 1998; 88(9):1377-80. PMC: 1509064. DOI: 10.2105/ajph.88.9.1377. View

18.

Kulldorff M, Zhang Z, Hartman J, Heffernan R, Huang L, Mostashari F . Benchmark data and power calculations for evaluating disease outbreak detection methods. MMWR Suppl. 2005; 53:144-51. View

19.

Tango T, Takahashi K . A flexibly shaped spatial scan statistic for detecting clusters. Int J Health Geogr. 2005; 4:11. PMC: 1173134. DOI: 10.1186/1476-072X-4-11. View

20.

Huang L, Kulldorff M, Gregorio D . A spatial scan statistic for survival data. Biometrics. 2007; 63(1):109-18. DOI: 10.1111/j.1541-0420.2006.00661.x. View