Application of geographical information systems (GIS) in epidemiological studies using the example of the ISAAC study Munich

Geographical Information Systems (GIS) are increasingly applied as modern t ools for analysis and visualization of health-related spatial data, especia lly in epidemiological research. GIS are used by medical researchers and ex ecutives in the public health service. A community-based survey was conduct ed according to the phase II protocol of the International Study of Asthma and Allergies in Childhood (ISAAC) in Munich. The spatial patterns of disea se incidence were analysed and related to exposure data by GIS. The prevale nce study on fourth-grade pupils (n=3354) and school beginners (n = 2890) w as conducted during the school term 1995/96 in Munich. Parental questionnai res and measurements of lung function and immunological parameters were use d. The questionnaire data were integrated in a GIS database. In this paper we discuss methodological aspects of GIS-based spatial analysis related to epidemiological data. In addition, we investigate whether there were spatia l clusters of children with wheeze in the last 12 months of a magnitude unl ikely to occur by chance and which could indicate local health risks. The s tudy was based on permutation tests where global and local methods were app lied. No spatial clusters of children with asthma symptoms were identified in the city of Munich.