Sampling bias in an international internet survey of diversion programs in the criminal justice system.
Despite advances in the storage and retrieval of information within health care systems, health researchers conducting surveys for evaluations still face technical barriers that may lead to sampling bias. The authors describe their experience in administering a Web-based, international survey to English-speaking countries. Identifying the sample was a multistage effort involving (a) searching for published e-mail addresses, (b) conducting Web searches for publicly funded agencies, and (c) performing literature searches, personal contacts, and extensive Internet searches for individuals. After pretesting, the survey was converted into an electronic format accessible by multiple Web browsers. Sampling bias arose from (a) system incompatibility, which did not allow potential respondents to open the survey, (b) varying institutional gate-keeping policies that "recognized" the unsolicited survey as spam, (c) culturally unique program terminology, which confused some respondents, and (d) incomplete sampling frames. Solutions are offered to the first three problems, and the authors note that sampling bias remains a crucial problem.
Hartford
Kathleen
K
Lawson Health Research Institute, London, Ontario, Canada N6A 4G5. kathleen.hartford043@sympatico.ca
Carey
Robert
R
Mendonca
James
J
D003219:Confidentiality; D003416:Criminal Law; D003625:Data Collection / Q000379:methods*; D006297:Health Services Accessibility; D006801:Humans; D020407:Internet; D007802:Language; D001523:Mental Disorders / Q000628:therapy*; D008605:Mental Health Services; D012107:Research Design; D015983:Selection Bias