Anne Pariser, MD, Director of the NCATS’ Office of Rare Diseases Research, explains why the lack of ICD codes for most rare conditions impedes diagnosis, treatment, and research.

In a recent NCATS study published in the Orphanet Journal of Rare Diseases, it was noted only about half of the 7,000 – 10,000 rare diseases can be mapped to a specific ICD code or cluster. That, along with the highly variable timelines between symptoms onset and an accurate diagnosis, can make it very difficult accurately portray the natural history or cost of care for a particular rare disease. 

Dr. Pariser is hopeful that machine learning and better diagnostic tools will improve how we more quickly identify and code for rare disease patients in the future. 

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Tisdale A, Cutillo CM, Nathan R et al. The IDeaS initiative: pilot study to assess the impact of rare diseases on patients and healthcare systems. Orphanet J Rare Dis 2021; 16: 429.