title: Model-based testing for space-time interaction using point processes: An application to psychiatric hospital admissions in an urban area.
abstract: Spatio-temporal interaction is inherent to cases of infectious diseases and occurrences of earthquakes, whereas the spread of other events, such as cancer or crime, is less evident. Statistical significance tests of space-time clustering usually assess the correlation between the spatial and temporal (transformed) distances of the events. Although appealing through simplicity, these classical tests do not adjust for the underlying population nor can they account for a distance decay of interaction. We propose to use the framework of an endemic-epidemic point process model to jointly estimate a background event rate explained by seasonal and areal characteristics, as well as a superposed epidemic component representing the hypothesis of interest. We illustrate this new model-based test for space-time interaction by analysing psychiatric inpatient admissions in Zurich, Switzerland (2007-2012). Several socio-economic factors were found to be associated with the admission rate, but there was no evidence of general clustering of the cases.
authors.affiliation: Epidemiology, Biostatistics and Prevention Institute (EBPI), University of Zurich, Hirschengraben 84, 8001 Zürich, Switzerland. Electronic address: sebastian.meyer@uzh.ch.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Meyer
authors.affiliation: Department of Psychiatry, Psychotherapy and Psychosomatics (DPPP), University Hospital of Psychiatry, Lenggstrasse 31,8032 Zürich, Switzerland.
authors.forename: Ingeborg
authors.initials: I
authors.lastname: Warnke
authors.affiliation: University Hospital of Psychiatry, Militärstrasse 8, 8021 Zurich, Switzerland.
authors.forename: Wulf
authors.initials: W
authors.lastname: Rössler
authors.affiliation: Epidemiology, Biostatistics and Prevention Institute (EBPI), University of Zurich, Hirschengraben 84, 8001 Zürich, Switzerland. Electronic address: leonhard.held@uzh.ch.
authors.forename: Leonhard
authors.initials: L
authors.lastname: Held
mesh_terms: D000328:Adult; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006778:Hospitals, Psychiatric; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D013029:Space-Time Clustering; D062211:Spatio-Temporal Analysis; D013557:Switzerland; D014505:Urban Population / Q000706:statistics & numerical data*
keywords: Global test of clustering; Knox test; Mantel test; Psychiatric inpatient admissions; Space–time K-function; Spatio-temporal point process