TY - JOUR T1 - Playing hard to get: field substitutions in health surveys. JF - Int J Public Health Y1 - 2007 A1 - Stefaan Demarest A1 - Lydia Gisle A1 - Johan Van der Heyden KW - Belgium KW - health surveys KW - Humans KW - Interviews as Topic KW - Logistic Models VL - 52 CP - 3 U1 - http://www.ncbi.nlm.nih.gov/pubmed/17958286?dopt=Abstract ER -