This is a demonstration of the temporal constraint structure tagger (TCStagger), developed by Li Zhou. TCStagger takes a segment of clinical text, and by using regular expressions, finds the temporal statements in the text and codes those statements into a structured format. The formal representation of the temporal information was defined in a 2006 JBI paper called A temporal constraint structure for extracting temporal information from clinical narrative.
TCStagger is available as a tar file (hripcsak@ columbia.edu). See also the ReadMe file.
Copyright 2006, Li Zhou, Department of Biomedical Informatics, Columbia University. This work was funded by National Library of Medicine grants R01 LM06910 "Discovering and applying knowledge in clinical databases"; R01 LM07659 "Capturing and Linking Genomic and Clinical Information;" and R01 LM07268 "Using Narrative Data to Enrich the Online Medical Record."
DEMONSTRATION
In the following demonstration, either type or paste text into the "Input text" text box and press send, or check one of the boxes for sample text. Under "Output text," you will find the processed text with the temporal expressions highlighted. Mousing over the expression will reveal the temporal encoding, which is explained in the table below it. Refer to the above paper for more information about the encoding.
| Tag | Description |
|---|---|
| event_point | endpoint(s) (the start and/or finish) of the event constrained by the temporal expression values: start, finish, unspecified (which endpoint of the event which is constrained is not explicitly stated in the text) |
| anchor | constraining time point values: can be a calendar date, a time of day, a relative date or time, an event, or a time reference (e.g. "at that time" can be encoded as "previous reference"). Each constraint structure can have more than one anchor (e.g. "between 1990 and 2000", has two anchors (1990 and 2000) comprising a time period) |
| anchor_point | if anchor is an event, the endpoint of the event is specified when possible. |
| anchor_modifier | indicates the stage of a period of time, or the course an event (e.g. anchor "1980s" in "early 1980s" has a modifier of "early") values: early, mid, and late |
| relation | a temporal relation between an endpoint of an event and its anchor or interval(s) constructed by the constraint structure with respect to the anchor values: equal, before, equal or before, after and equal or after |
| TUNIT | unit for measuring time periods values: of second, minute, hour, day, week, month, and year |
| quantity | specified or indefinite number or amount for measuring the length of a time period values: a number or a vague quantifier (e.g. many, a few) |
| direction | indicates the direction of an interval relative to its anchor values: minus (in the past), plus (in the future), or both (e.g. "within two days") |
| interval_operator |
characterizes an endpoint of the event values: drag (continuous period of time within an interval) and jump (located at the distal end of the interval) |
| vagueness |
indicates if a vagueness modifier is contained within the expression (e.g. approximately, about, roughly, and more or less) value: yes |