Data were drawn from a population - based study that constituted part of a nationwide ongoing longitudinal study in Japan [20, 22]. (journals.plos.org)
Thirty - three people who reported recent recreational use of gabapentin were recruited from two ongoing longitudinal studies of drug users to participate in focus groups. (sciencedaily.com)
NCDS is an ongoing longitudinal study of some 17,000 children who were born in England, Wales and Scotland in one week in 1958. (fatherhoodinstitute.org)