PT - JOURNAL ARTICLE AU - Hempel, Susanne AU - Danz, Margie AU - Robinson, Karen A AU - Bolshakova, Maria AU - Rodriguez, Jesus AU - Mears, Alanna AU - Pham, Cindy AU - Yagyu, Sachi AU - Motala, Aneesa AU - Tolentino, Danica AU - Akbari, Omid AU - Johnston, Jill TI - Multiple chemical sensitivity scoping review protocol: overview of research and MCS construct AID - 10.1136/bmjopen-2023-072098 DP - 2023 Sep 01 TA - BMJ Open PG - e072098 VI - 13 IP - 9 4099 - http://bmjopen.bmj.com/content/13/9/e072098.short 4100 - http://bmjopen.bmj.com/content/13/9/e072098.full SO - BMJ Open2023 Sep 01; 13 AB - Introduction Multiple chemical sensitivity (MCS) has been characterised by reported adverse responses to environmental exposures of common chemical agents (eg, perfumes, paint, cleaning products and other inhaled or ingested agents) in low doses considered non-toxic for the general population. There is currently no consensus on whether MCS can be established as a distinct disorder.Methods and analysis The scoping review of the literature will be guided by five questions: How is MCS defined and which diagnostic criteria have been proposed? What methods are used to report prevalence and incidence estimates of MCS? What are the characteristics of the body of scientific evidence that addresses whether MCS is a distinct disorder or syndrome? What underlying mechanisms for MCS have been proposed in the scientific literature? Which treatment and management approaches for MCS have been evaluated in empirical research studies? We will conduct a comprehensive search in 14 research databases. Citation screening will be supported by machine learning algorithms. Two independent reviewers will assess eligibility of full-text publications against prespecified criteria. Data abstraction will support concise evidence tables. A formal consultation exercise will elicit input regarding the review results and presentation. The existing research evidence will be documented in a user-friendly visualisation in the format of an evidence map.Ethics and dissemination Determined to be exempt from review (UP-22-00516). Results will be disseminated through a journal manuscript and data will be publicly accessible through an online data repository.Registration details The protocol is registered in Open Science Framework (osf.io/4a3wu).