A bibliometric analysis of multimorbidity from 2005 to 2019

Context: Multimorbidity is frequently seen in primary care. We aimed to identify and analyze publications on multimorbidity, including those that most influenced this field. Method: A bibliometric analysis of publications from 2005 to 2019 in the PubMed database containing “multimorbidity” or “multi-morbidity” identified with the tool iCite. We analyzed the number of publications, total citations, the article-level metric Relative Citation Ratio (RCR), type of study, and journals with the most cited articles. Results: The number of publications using “multimorbidity” has continuously increased since 2005 (2005–2009: 138; 2010–2014: 823; 2015–2019: 3068). The median number of total citations per article was 3. The median RCR was 1.04. Articles with RCR at or above the 97th percentile (RCR = 7.43) were analyzed in detail (n = 104). In 34 publications of this subgroup (33%), the word multimorbidity was used but was not the subject of study. The remaining top 70 publications included 32 observational studies, 22 reviews, five guideline statements, three analysis papers, two randomized trials, three qualitative studies, two measurement development reports, and one conceptual framework development report. The publications were produced by authors from 32 countries. They were published in 37 different journals, ranging from one to four articles in the same journal. Conclusions: We found a continuous increase in the number of publications about multimorbidity since 2005. However, our study suggests that the numbers should be considered only a general trend because multimorbidity was not the main subject in 33% of publications in a subgroup of 104 analyzed in detail.