Jean?François Etter|Thomas Perneger
A comparison of cigarette smokers recruited through the Internet or by mail
Institute of Social and Preventive Medicine|University of Geneva
compare smokers recruited mail interneta questionnaire mailed 19352 inhabitants switzerland 1998 effort enroll smoking cessation trial questionnaire also available internet furthermore mailed survey representative sample n 1000 population geneva switzerland 1996 study compare three groups 1027 smokers recruited internet 2961 volunteer trial participants recruited mail response rate 16 211 smokers representative sample also recruited mail response rate 75smokers selfrecruited internet younger educated motivated quit smoking smoked cigarettes per day smokers samples compared trial participants internet participants negative attitudes towards smoking higher selfefficacy scores addicted tobacco strength associations smokingrelated variables similar internet trial participantsas expected three groups smokers differed several characteristics however bias distributions variables imply bias associations variables thus internet recruitment potentially useful method analytical studies focus associations variables