There are multiple definitions:

1. extent of defect(English)

   • CFA, COHIP-SF, DFS
   • Dentistry, Questionnaire
   • https://doi.org…25.2012.00338.x

2. early-onset (adult) depression(English)

   • potentially divergent pathological mechanisms compared to late-onset (adult) depression
   • lOFC, MDD, MRI, rACC, cACC, CT, LOD
   • Depression, Pathology
   • https://doi.org…000000000001314

3. early-onset disease(English)

   • meningitis is less common than in LOD
   • GBS, LOD
   • Neonatal situation, Infection
   • https://doi.org…4.45.2.20230533