Geographical information systems as a tool for monitoring tobacco industry advertising.
Although the use of a geographical information systems (GIS) approach is usually applied to epidemiological disease outbreaks and environmental exposure mapping, it has significant potential as a tobacco control research tool in monitoring point-of-purchase (POP) tobacco advertising. An ecological study design approach was applied so as to primarily evaluate and interpret the spatial density and intensity of POP and tobacco industry advertisements within <300 m to high schools in Greece with the application of GIS methodology combining mapping, photographing and global positioning data. The GIS approach identified 133 POP and 44 billboards within 300 m of the school gates of Heraklion schools. On average 13 POP (range 4-21) and 4.4 billboards (range 1-9) were located per school, and all had at least 1 POP within 20 m of the school gate. On average (SD) 9 (6) tobacco advertisements per POP (range 0-25) were noted, and 80% of them were below child height. The GIS protocol identified that kiosks, that were excepted from the Greek ban on tobacco advertising, in comparison to other POP, were found not only to be closer and visible from the school gates (44.1% vs 10.8%, p<0.001) but were also found to have more external advertisements (8 (5) vs 5 (3), p<0.001). This study demonstrates the effectiveness of a GIS system in monitoring tobacco industry advertising on a large population-based scale and implies its use as a standardised method for monitoring tobacco industry strategies and tobacco control efforts.