(Un)standardized testing: the diagnostic odyssey of children with rare genetic disorders in Alberta, Canada



We provide a description of the diagnostic odyssey for a cohort of children seeking diagnosis of a rare genetic disorder in terms of the time from initial consultation to most recent visit or receipt of diagnosis, the number of tests per patient, and the types of tests received.


Retrospective chart review of 299 children seen at the Alberta Children’s Hospital (ACH) Genetics Clinic (GC) for whom the result of at least one single-gene test, gene panel, or chromosome microarray analysis (CMA) was recorded.


Of 299 patients, 90 (30%) received a diagnosis in the period of the review. Patients had an average of 5.4 tests each; 236 (79%) patients received CMA; 172 (58%) patients received single-gene tests and 34 (11%) received gene panels; 167 (56%) underwent imaging/electrical activity studies. The mean observation period was 898 days (95% confidence interval [CI] 791, 1004). Among patients with visits recorded prior to visiting ACH GC, 43% of the total observation time occurred prior to the GC.


As genomic technologies expand, the nature of the diagnostic odyssey will change. This study has outlined the current standard of care in the ACH GC, providing a baseline against which future changes can be assessed.

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This research was funded by a Seed Grant from the Cumming School of Medicine (CSM) and Alberta Health Services (AHS) Clinical Research Fund at the University of Calgary. C.M-I. is funded by an Alberta Innovates Postgraduate Scholarship and a Network of Alberta Health Economists (NOAHE) Fellowship award. D.A.M. is funded by the Arthur J.E. Child Chair in Rheumatology Outcomes Research and a Canada Research Chair in Health Services and Systems Research.

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Correspondence to Christine Michaels-Igbokwe PhD.

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Michaels-Igbokwe, C., McInnes, B., MacDonald, K.V. et al. (Un)standardized testing: the diagnostic odyssey of children with rare genetic disorders in Alberta, Canada. Genet Med (2020). https://doi.org/10.1038/s41436-020-00975-0

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  • genetic disorders
  • pediatric
  • children
  • diagnostic odyssey