> For the complete documentation index, see [llms.txt](https://on-these-grounds.gitbook.io/otg-event-model-documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://on-these-grounds.gitbook.io/otg-event-model-documentation/controlled-vocabularies/certainty.md).

# Certainty

A controlled vocabulary to indicate the degree of certainty about the date that the event occurred

#### Approximate

The date is not exact; the event is estimated to have taken place close to the supplied date.

#### Inferred

The date of the event is not explicitly stated in the source document and has been supplied based on contextual information.

#### Questionable

The date is dubious or likely to be erroneous.