You will be presented with a citation segment from the section of an NLP research paper, as well as the context surrounding that citation. Classify the intent behind this citation by choosing from one of the following categories:
- Background: provides context or foundational information related to the topic.
- Extends: builds upon the cited work.
- Uses: applies the methods or findings of the cited work.
- Motivation: cites the work as inspiration or rationale for the research.
- CompareOrContrast: compares or contrasts the cited work with others.
- FutureWork: cites the work as a direction for future research.

Your answer should be a single word from the following list of options: ["Background", "Extends", "Uses", "Motivation", "CompareOrContrast", "FutureWork"]. Do not include any other text in your response.

Section Title:
None

Context before the citation:
Our knowledge extractors rely extensively on MetaMap (Aronson 2001), a system for identifying segments of text that correspond to concepts in the UMLS Metathesaurus. Each individual PICO extractor takes as input the abstract text of a MEDLINE citation and identifies the relevant elements: Outcomes are complete sentences, while population, problems, and interventions are short noun phrases. For an example of a completely annotated abstract, see Figure 2.

Citation Sentence:
Our knowledge extractors rely extensively on MetaMap ( Aronson 2001 ) , a system for identifying segments of text that correspond to concepts in the UMLS Metathesaurus .

Context after the citation:
Many of our algorithms operate at the level of coarser-grained semantic types called Semantic Groups (McCray, Burgun, and Bodenreider 2001), which capture higher-level generalizations about entities (e.g., CHEMICALS & DRUGS). An additional feature we take advantage of (when present) is explicit section markers present in some abstracts. These so-called structured abstracts were recommended by the Ad Hoc Working Group for Critical Appraisal of the Medical Literature (1987) to help humans assess the reliability and content of a publication and to facilitate the indexing and retrieval processes. These abstracts loosely adhere to the introduction, methods, results, and conclusions format common in scientific writing, and delineate a study using explicitly marked sections with variations of the above headings.
Uses