Psychosocial Determinants of Attrition in a Longitudinal Study of Tobacco Use in Youth

Table 1

Responders, nonresponders, and dropouts at each followup survey, The BROMS Cohort Study, 1998–2005.

	Followup survey
	1	2	3	4	5	6
Available cohort* members	3020	3011	2976	2952	2910	2852
Responders	2904	2882	2809	2689	2621	2489
(%)	(96.2)	(95.7)	(94.4)	(91.1)	(90.1)	(87.3)
Non responders	107	94	143	221	231	350
(%)	(3.5)	(3.1)	(4.8)	(7.5)	(7.9)	(12.2)
Drop-outs	9	35	24	42	58	13
(%)	(0.3)	(1.2)	(0.8)	(1.4)	(2.0)	(0.5)

*Available cohort members are students who had not left permanently the cohort at the time of the survey.