From: A randomised controlled trial comparing opt-in and opt-out home visits for tracing lost participants in a prospective birth cohort study
Number of YPs who consented to participate in ALSPAC
Opt-in N = 3
Opt-out N = 24a
Data linkage discussed
3 (100 %)
22 (92 %)
Consent to at least one type of data linkageb
Consent to any data linkage refused
0 (0 %)