Development of the Geographical Proportional-to-size Street-Intercept Sampling (GPSIS) method for recruiting urban nightlife-goers in an entire city

Abstract

We developed the Geographical Proportional-to-size Street-Intercept Sampling (GPSIS) method in order to obtain a sample of nightlife-goers which accounted for the diversity of spaces, patrons and locations within two Swiss cities. Popular nightlife zones were identified and quantified using social media data and local experts’ knowledge. Young people were recruited in the streets on Friday and Saturday nights on three consecutive weekends using the ‘fixed-line method, pro-rated for the zone’s estimated popularity. Of the 3092 young adults approached, 896 agreed to pre-register. The importance of recruitment in multiple zones and over multiple weekend-days was evidenced by significant variations in participant demographics and registration rates between recruitment zones, times and weather conditions. To conclude, by combining a geographical approach with in situ recruitment, GPSIS has considerable potential as a tool for recruiting samples that represent the diversity of the nightlife population and spaces.

Keywords:

• Recruitment method
• nightlife
• young adults
• social media

Acknowledgements

We are extremely grateful to Vera Bäriswyl, Lucie Chambeyron, Anna Katz and Pauline Ndondo for their assistance with the street recruitment process and for supporting the participants in the following months. We would also like to thank Christian Ball, Laura Bazzi, Lilian Becker, Cornelia Bieri, Stefanie Bovet, Elodie Cachelin, Silvan Christen, Stefanie Eberle, Peter Hotzendorfer, Florence Lepdor, Josephine Marfurt, Petra Meier, Mehdi Mhidi, Fanya Nicoli, Bansoa Sigam, Tamara Stojanovic, Hannes Tobler, Larissa Zollinger and Lea Zust for their contribution to the recruitment in the streets of Lausanne and Zurich. Last but not least, we would like to express our gratitude to all the participants in the Youth@Night study.