Response rates and selection problems, with emphasis on mental health variables and DNA sampling, in large population-based, cross-sectional and longitudinal studies of adolescents in Norway.
Bjertness
Espen
E
Section for Preventive Medicine and Epidemiology, Institute of General Practice and Community Medicine, Faculty of Medicine, University of Oslo, Box 1130 Blindern, 0318 Oslo, Norway. espen.bjertness@medisin.uio.no
Sagatun
Ase
A
Green
Kristian
K
Lien
Lars
L
Søgaard
Anne Johanne
AJ
Selmer
Randi
R