Grant: Institute of Genetics Clinical Investigatorship Award

Developmental delay affects 1% of all children aged 0-4 years in Canada. Common genetic causes include chromosomal rearrangements and monogenic diseases. It is thought that identifying the underlying genetic cause of disease will improve clinical management through anticipatory guidance and better access to appropriate supportive services, and enable parents to make informed reproductive decisions. The evaluation of children with developmental delay is the topic of clinical practice guidelines from the American Academy of Pediatrics, the American Academy of Neurology, and the American College of Medical Genetics, but not from relevant Canadian professional associations.Genetic tests commonly used to evaluate children with developmental delay include karyotype, fragile X testing, and more recently comparative genomic hybridization (CGH). That their use is appropriate in practice remains to be determined. The research program that we propose will: 1) summarize the suggested practice pattern found in guidelines and evaluate the quality of the guidelines using existing guideline evaluation tools (GRADE, AGREE, etc.); 2) study how genetic tests are used in practice (observed use) and how physicians perceive their use (reported use); 3) compare observed, reported, and suggested practice patterns obtained in 1) and 2); 4) determine which factors influence test use patterns (and where practice guidelines play a role); 5) characterize the clinical utility of these genetic tests from the medical (impact on patient management) and parental (impact on access to services and reproductive decisions) perspectives. This will be achieved using multiple sources and methods: a systematic medical chart review of children evaluated for global developmental delay in our center, surveys and qualitative interviews of relevant Quebec physicians, and surveys and qualitative interviews of parents of children who have been evaluated for global developmental delay.