title: Utilizing social media data for pharmacovigilance: A review.
abstract: OBJECTIVE
  Automatic monitoring of Adverse Drug Reactions (ADRs), defined as adverse patient outcomes caused by medications, is a challenging research problem that is currently receiving significant attention from the medical informatics community. In recent years, user-posted data on social media, primarily due to its sheer volume, has become a useful resource for ADR monitoring. Research using social media data has progressed using various data sources and techniques, making it difficult to compare distinct systems and their performances. In this paper, we perform a methodical review to characterize the different approaches to ADR detection/extraction from social media, and their applicability to pharmacovigilance. In addition, we present a potential systematic pathway to ADR monitoring from social media.
  
  
  METHODS
  We identified studies describing approaches for ADR detection from social media from the Medline, Embase, Scopus and Web of Science databases, and the Google Scholar search engine. Studies that met our inclusion criteria were those that attempted to extract ADR information posted by users on any publicly available social media platform. We categorized the studies according to different characteristics such as primary ADR detection approach, size of corpus, data source(s), availability, and evaluation criteria.
  
  
  RESULTS
  Twenty-two studies met our inclusion criteria, with fifteen (68%) published within the last two years. However, publicly available annotated data is still scarce, and we found only six studies that made the annotations used publicly available, making system performance comparisons difficult. In terms of algorithms, supervised classification techniques to detect posts containing ADR mentions, and lexicon-based approaches for extraction of ADR mentions from texts have been the most popular.
  
  
  CONCLUSIONS
  Our review suggests that interest in the utilization of the vast amounts of available social media data for ADR monitoring is increasing. In terms of sources, both health-related and general social media data have been used for ADR detection-while health-related sources tend to contain higher proportions of relevant data, the volume of data from general social media websites is significantly higher. There is still very limited amount of annotated data publicly available , and, as indicated by the promising results obtained by recent supervised learning approaches, there is a strong need to make such data available to the research community.
authors.affiliation: Department of Biomedical Informatics, Arizona State University, Scottsdale, AZ, United States. Electronic address: abeed.sarker@asu.edu.
authors.forename: Abeed
authors.initials: A
authors.lastname: Sarker
authors.affiliation: Department of Biomedical Informatics, Arizona State University, Scottsdale, AZ, United States.
authors.forename: Rachel
authors.initials: R
authors.lastname: Ginn
authors.affiliation: Department of Biomedical Informatics, Arizona State University, Scottsdale, AZ, United States.
authors.forename: Azadeh
authors.initials: A
authors.lastname: Nikfarjam
authors.affiliation: Department of Biomedical Informatics, Arizona State University, Scottsdale, AZ, United States.
authors.forename: Karen
authors.initials: K
authors.lastname: O'Connor
authors.affiliation: Rueckert-Hartman College for Health Professions, Regis University, Denver, CO, United States.
authors.forename: Karen
authors.initials: K
authors.lastname: Smith
authors.affiliation: School of Computing, Informatics, and Decision Systems Engineering, Arizona State University, Tempe, AZ, United States.
authors.forename: Swetha
authors.initials: S
authors.lastname: Jayaraman
authors.affiliation: School of Computing, Informatics, and Decision Systems Engineering, Arizona State University, Tempe, AZ, United States.
authors.forename: Tejaswi
authors.initials: T
authors.lastname: Upadhaya
authors.affiliation: Department of Biomedical Informatics, Arizona State University, Scottsdale, AZ, United States.
authors.forename: Graciela
authors.initials: G
authors.lastname: Gonzalez
mesh_terms: D016907:Adverse Drug Reaction Reporting Systems; D006801:Humans; D020407:Internet; D016239:MEDLINE; D060735:Pharmacovigilance; D011634:Public Health; D061108:Social Media
keywords: Adverse drug reaction; Pharmacovigilance; Social media