“…The ACSF participation rate was 76.6% (ACSF Investigators, 1992), which is higher than or equivalent to rates obtained in most surveys on adult populations (Breakwell and Fife-Schaw, 1992;Catania et al, 1992aCatania et al, , 1992bCatania et al, , 1990De Vroome et al, 1990;Johnson et al, 1992;Levy et al, 1988;Melbye and Biggar, 1992;Quenel et al, 1991;Sundet et al, 1989). Such a high rate in a telephone survey might be due to the use of an advance letter and to the suitable wording of this letter (ACSF Group, 1992;Groves et al, 1988).…”