Table 1.

Coverage of congenital myasthenic syndromes by the major medical coding systems

Coding system	Terminology browser used	Coding for congenital myasthenic syndromes class/category	Coding for individual CMS types
International Classification of Disease (ICD) Revision 11	https://icd.who.int/browse11/l-m/en	8C61: Congenital myasthenic syndromes	No coding but textual description of four categories: Congenital myasthenic syndrome with presynaptic defect, Synaptic basal lamina-associated CMS, Congenital myasthenia with postsynaptic defect, CMS with glycosylation deficiency, Unidentified CMS.
International Classification of Disease (ICD) Revision 10	http://apps.who.int/classifications/icd10/browse/2016/en	G70.2: Congenital and developmental myasthenia	Not present
Medical Subject Headings (MeSH)	https://meshb.nlm.nih.gov/search	C16.320.590: Myasthenic Syndromes, Congenital	Not present
Systematized Nomenclature of Medicine – Clinical Terms (SNOMED CT)	http://browser.ihtsdotools.org/	230672006: Congenital myasthenia (disorder)	Not present
Orphanet nomenclature of rare diseases	https://www.orpha.net/consor/cgi-bin/Disease.php?lng=EN	ORPHA:590: Congenital myasthenic syndrome	Most granular level is absent. Subclasses are defined: Postsynaptic congenital myasthenic syndromes Presynaptic congenital myasthenic syndromes Synaptic congenital myasthenic syndromes Congenital myasthenic syndromes with glycosylation defect
Online Mendelian Inheritance in Man (OMIM)	http://omim.org/	N/A	Coding of 28 out of 39 entities with “phenotype MIM number” (for detail see Table 2) No hierarchies/ontological features