About ORMEL J
About Univ. Groningen, NLD
About VONKORFF M
About Group Health Cooperative of Puget Sound, Wash
About USTUN T B
About WHO Collaborative Study, World Health Organization, Geneva, CHE
About PINI S
About Univ. Verona, ITA
About KORTEN A
About Australian National Univ. Canberra
About OLDEHINKEL T
About Univ. Groningen, NLD
About Journal of the American Medical Association
About WHO