German NegEx Trigger Set

Our trigger set is described in our BioTxtM 2016 paper (see paper below). It can be used in combination with NegEx in order to detect negations and speculations in German clinical data. The trigger set has been created by a native speaker, based on the trigger set multilingual_lexicon-en-de-fr-sv.csv which can be found on this webpage (see medinfo_2013_multilingual_negex_lexicon_v1_April30th2013.zip).

Following steps were performed:

  • Source-Original ConText terms have been selected.
  • Translations and alternative translations have been reviewed and in some cases corrected.
  • New alternative translations have been added.
  • Regular expressions have been expanded.
  • Scope (of negations) has been determined taking into account GE Action, Category and our opinion. In many cases "surrounding triggers", such as "lehnt ... ab" (reject) and "wies ... zurück" (declined) where shorten and only one part of them was taken into account.

Download: negex_trigger_german_biotxtm_2016.txt

NOTE: In order to make the trigger set work, the following two changes have to be applied to negex.python.zip (Jul 7, 2009). Replace line:

pattern = r'\b(' + trig + r')\b'

with:

if trig == "\?":
   pattern = r'(' + trig + r')'
else:
   pattern = r'\b(' + trig + r')\b'

and line:

sb3 = sb3 + ' ' + sentenceTokens[i]

with:

sb3.append(sentenceTokens[i])

We are happy if you acknowledge our work :-)
Negation Detection in Clinical Reports Written in German, Viviana Cotik, Roland Roller, Feiyu Xu, Hans Uszkoreit, Klemens Budde and Danilo Schmidt, In Proceedings of the 5th Workshop on Building and Evaluating Resources for Biomedical Text Mining (BioTxtM), 2016, Osaka, Japan [PDF][BibTex]