Table 1.

 MedDRA hierarchical structure

No of terms	Level of term	Example
26	System organ class (SOC)	Psychiatric disorder
>330	High level group terms (HLGT)	Suicidal and self injurious behaviour NEC
>1700	High level terms (HLT)	Suicidal and self injurious behaviour
>20 000	Preferred terms (PT)	Suicidal ideation
>70 000	Lowest level terms (LLT)	Suicidal tendency, active suicidal ideation, death wishes, life weariness, passive suicidal ideation, suicidal ideation, suicidal intention, suicidal plans

MedDRA=Medical Dictionary for Regulatory Activities; NEC=not elsewhere classified.