GENERAL POPULATION SURVEY METHODOLOGY Janusz Sieroslawski Institute of Psychiatry and Neurology Warsaw GENERAL POPULATION SURVEY METHODOLOGY General population survey (GPS) on prevalence and consumption of drugs, opinion, knowledge about drugs and risk Belgrad, 25th of February – 1st of March 2013

Population surveys in Poland Quite long tradition of the countrywide general population surveys focused on alcohol consumption (1962, 1968, 1976, 1984, 1989, 1993, 1995, 1998, 2002, 2006, 2010) Questions on drug use in 1984 and 1989 included – only a few cases of illicit drug use found In 1997 first general population survey on drug use covering Warsaw only Since 2002 country wide population surveys each 4 years (2006, 2010)

Aims and objectives of the studies Monitoring of drug use and alcohol consumption and exploring of attitudes toward drug and alcohol problem as a aim of the study Objectives of the study related to the drugs to assess prevalence of occasional drug use in general population to identify factors of occasional drug use to explore attitudes toward drug addiction and various approaches to drug policy

Study design Studies commissioned by National Bureau for Drug Prevention Field work conducted by contracted agency Target population – Poland’s inhabitants age 15-64 Respondents selection: random sample Data collection technique – face-to-face interview (pen and paper) Data processing using SPSS PC

Questionnaire -1 Questionaire developed on the basis of EMQ Questions with predefined answers Drugs, alcohol, tobacco, prescribed drugs under study Particular drugs use explored in life-time, last 12 months and last 30 days time frame (number of times, age of onset)

Questionnaire -2 Indicators of drugs availability (perceived availability, exposer to drug offers) Alcohol consumption measurement in 12 months time frame Beverage Specific Quantity Frequency method Screening instruments (AUDIT) Nominations for „benchmark” estimation Opinions on drug problem and different approaches to the problem

Population Territorial (geographical) coverage Age coverage Countrywide Overrepresentations of some regions Age coverage 15-64 Overrepresentations of 15-34 Inhabitants of Poland regardless nationality Stay as a criterion instead of registration People living in institutions (prison, shelter, military barracks) excluded

Sampling Sampling method – multistage stratified random sample with overrepresentations of some subpopulations First stage – small geographical areas Second stage – households Third stage - respondents Sampling frame – electronic data base of haushold addresses Sampling output – houshold addresses Weighting procedure to reduce bias (gender, age and education level)

Weighting Weighting procedure to reduce bias related to: overrepresentations nonresponses gender age groups rural – urban areas Weighting lead to sample size reduction

Data collection – field work procedure Pilot study – to test questionnaire and fieldwork procedures Special training procedure for interviewers: practical exercise interviewing instruction for interviewers in the written form probation interview to test interviewers’ skills Field control of the interviewers’ job The letter explaining study and announcing interviewers’ visit sent before field work phase Interview duration: 45-60 minutes

Interviewer bias Substance use very sensitive issue Interviewer could influence respondents answers by manifesting own attitudes Interviewer have to establish confidence and provide a sense of security Selection of interviewers Interviewers training focus on: how to establish confidence and provide a sense of security how to avoid manifestation of own attitudes

Ethical issues Anonymity of respondents as the crucial factor of the data reliability Data protection mechanisms applied: interviewers obliged to keep secret of information collected and to protect data respondents’ names always separated from the fulfilled questionnaires face-to-face interview always without presence of other persons data base without names Agreement of respondent for giving interview requested