1. Department of Pediatrics; University of British Columbia; Vancouver BC Canada
2. Department of Pediatrics; McMaster University; Hamilton ON Canada
3. International Classification of Functioning, Disability and Health Research Branch in Co-Operation with the World Health Organization Collaborating Centre for the Family of International Classifications in Germany; German Institute of Medical Documentation and Information; Nottwil Switzerland
4. School of Population and Public Health; University of British Columbia; Vancouver BC Canada