Dates

The eds.dates pipeline's role is to detect and normalise dates within a medical document. We use simple regular expressions to extract date mentions.

Scope

The eds.dates pipeline finds absolute (eg 23/08/2021) and relative (eg hier, la semaine dernière) dates alike. It also handles mentions of duration.

Type	Example
absolute	3 mai, 03/05/2020
relative	hier, la semaine dernière
duration	pendant quatre jours

See the tutorial for a presentation of a full pipeline featuring the eds.dates component.

Usage

import spacy

import pendulum

nlp = spacy.blank("fr")
nlp.add_pipe("eds.dates")

text = (
    "Le patient est admis le 23 août 2021 pour une douleur à l'estomac. "
    "Il lui était arrivé la même chose il y a un an pendant une semaine. "
    "Il a été diagnostiqué en mai 1995."
)

doc = nlp(text)

dates = doc.spans["dates"]
dates
# Out: [23 août 2021, il y a un an, pendant une semaine, mai 1995]

dates[0]._.date.to_datetime()
# Out: 2021-08-23T00:00:00+02:00

dates[1]._.date.to_datetime()
# Out: -1 year

note_datetime = pendulum.datetime(2021, 8, 27, tz="Europe/Paris")

dates[1]._.date.to_datetime(note_datetime=note_datetime)
# Out: DateTime(2020, 8, 27, 0, 0, 0, tzinfo=Timezone('Europe/Paris'))

date_3_output = dates[3]._.date.to_datetime(
    note_datetime=note_datetime,
    infer_from_context=True,
    tz="Europe/Paris",
    default_day=15,
)
date_3_output
# Out: DateTime(1995, 5, 15, 0, 0, 0, tzinfo=Timezone('Europe/Paris'))

Declared extensions

The eds.dates pipeline declares one spaCy extension on the Span object: the date attribute contains a parsed version of the date.

Configuration

The pipeline can be configured using the following parameters :

Parameter	Explanation	Default
absolute	Absolute date patterns, eg le 5 août 2020	None (use pre-defined patterns)
relative	Relative date patterns, eg hier)	None (use pre-defined patterns)
durations	Duration patterns, eg pendant trois mois)	None (use pre-defined patterns)
false_positive	Some false positive patterns to exclude	None (use pre-defined patterns)
detect_periods	Whether to look for dates around entities only	False
on_ents_only	Whether to look for dates around entities only	False
attr	spaCy attribute to match on, eg NORM or TEXT	"NORM"

Authors and citation

The eds.dates pipeline was developed by AP-HP's Data Science team.