The City of The Hague monitors the use of Alcohol and Other Drugs (AOD) in the town‘s nightlife since 2002. Nightlife par ticipants, although not completely underground, are a „hidden“ or „hard to reach“ population for which there is no sampling framework available. Time–Location and Snowball Sampling are often used in studies of hidden populations, but these methods produce biased results and do not provide the basis for valid generalizations towards populations. Respondent Driven Sampling (RDS) was designed to overcome some of these limitations. Combining a modified form of snowball sampling with a mathematical system for weighting the sample, RDS produces unbiased estimators and standard errors or confidence intervals. RDS is successfully applied in various vulnerable (IDUs, non-IDUs, CSW, MSM) and less vulnerable populations (recreational drug users, nightlife participants, Jazz musicians) and has become the „Golden Standard“ for sampling hidden populations. As in the Netherlands internet connectivity is approaching 100% in our target popula- tion, we have developed a novel application to conduct RDS studies on the internet. Combining RDS with internet technology strengthens and automates the entire survey process. All steps in the research process (sampling, interviewing and distri- bution of incentives) are conducted online, producing analyzable net work and survey data instantly, minimizing e.g. interviewer bias, while the application of RDS greatly improves the reliability of internet survey data. In September 2008 the application will be used for the first time to draw a sample of 1500 nightlife participants. This presentation will discuss the internet appli- cation and methodology of Project Residence, the first community based WEB-RDS study. Jean-Paul C. Grund is a drug policy schol- ar, specialized in f ield studies of drug use, and its social, health and policy con- comitants. In the recent past, Dr. Grund conducted a study of drug use and HIV risks among the Roma/Gypsy popula- tion of Central and Eastern Europe and evaluation studies of needle exchange in Russia and Eastern Europe. He was the founding Director of the International Harm Reduction Development program at The Lindesmith Center, which fostered the development of practical harm reduc- tion programs in Central Eastern Europe and Russia. He also was the first Research Fellow in Residence at this New York based drug policy research center, which is part of the Open Society Institute. Dr. Grund holds an advanced degree in Clinical and Developmental Psychology from Utrecht University and received a Ph.D. in Social Science from the Medical and Health Sciences Faculty at Erasmus University in Rotterdam, The Netherlands. Dr. Grund is the author of numerous articles and two books on drug use culture, HIV, and their social-politi- cal determinants.

The Hague Municipal Health Service Dept of Epidemiology Hague

First global conference on methamphetamine science, strategy and response, Prague, 15-16 September 2008