Author contributions
IKH and UR designed the study, IKH obtained funding,
UR conducted the intervention, MR conducted the analysis
and drafted the manuscript, IKH and UR acted as coreaders
in the analysis and commented on the drafts.
Ethical approval
Ethical approval was granted by the Regional Ethics
Committee at the Faculty of Medicine, Uppsala University,
Dnr 02-366.
Funding
Grants were received from the Swedish Research Council
(Vetenskapsradet) Dnr 522-2005-7461 and the Faculty of
Medicine, Uppsala University, Sweden.