Use of geofencing interventions in population health research: a scoping review.

OBJECTIVES: Technological advancements that use global positioning system (GPS), such as geofencing, provide the opportunity to examine place-based context in population health research. This review aimed to systematically identify, assess and synthesise the existing evidence on geofencing intervention design, acceptability, feasibility and/or impact. DESIGN: Scoping review, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews guidance for reporting. DATA SOURCES: PubMed, CINAHL, EMBASE, Web of Science, Cochrane and PsycINFO for articles in English published up to 31 December 2021. ELIGIBILITY CRITERIA: Articles were included if geofencing was used as a mechanism for intervention delivery. EXCLUSION CRITERIA: (1) a component or combination of GPS, geographical information system or ecological momentary assessment was used without delivery of an intervention; (2) did not include a health or health-related outcome from the geofencing intervention; or (3) was not a peer-reviewed study. DATA EXTRACTION AND SYNTHESIS: Several researchers independently reviewed all abstracts and full-text articles for final inclusion. RESULTS: A total of 2171 articles were found; after exclusions, nine studies were included in the review. The majority were published in 5 years preceding the search (89%). Geofences in most studies (n=5) were fixed and programmed in the mobile application carried by participants without their input. Mechanisms of geofencing interventions were classified as direct or indirect, with five studies (56%) using direct interventions. There were several different health outcomes (from smoking to problematic alcohol use) across the five studies that used a direct geofencing intervention. CONCLUSIONS: This scoping review found geofencing to be an emerging technology that is an acceptable and feasible intervention applied to several different populations and health outcomes. Future studies should specify the rationale for the locations that are geofenced and user input. Moreover, attention to mechanisms of actions will enable scientists to understand not only whether geofencing is an appropriate and effective intervention but why it works to achieve the outcomes observed.

Investigation of Early Syphilis Trends Among Men Who Have Sex With Men to Identify Gaps in Screening and Case-Finding in Baltimore City, Maryland.

BACKGROUND: Syphilis incidence is increasing across the United States among men who have sex with men (MSM). Early latent (EL) versus primary and secondary (P&S) syphilis may be an indicator of delayed diagnosis and increased opportunity for transmission. To inform syphilis control strategies and identify potential gaps in case finding, we described recent syphilis trends among MSM and compared characteristics of syphilis cases by diagnosis stage. METHODS: We used public health surveillance data on P&S and EL syphilis diagnoses reported to the Baltimore City Health Department between 2009 and 2015. Differences across diagnosis stage were assessed using Cochran-Armitage and χ tests. RESULTS: Between 2009 and 2015, Baltimore City Health Department received 2436 reports of P&S and EL diagnoses. The majority (61%) of reports were among MSM, among whom 86% were black and 67% were human immunodeficiency virus (HIV)-infected. During this period, P&S and EL syphilis increased by 85% and 245%, respectively (P < 0.0001). MSM with EL versus P&S syphilis were similarly likely to be Black, more likely to be older (P < 0.05), HIV coinfected (P < 0.001), and diagnosed in private health care settings (P < 0.0001), but less likely to report multiple (P < 0.001) and anonymous sex partners (P < 0.001). CONCLUSIONS: In Baltimore City, syphilis diagnoses, particularly EL diagnoses, are increasing rapidly and are concentrated among Black HIV-infected MSM. Significant gaps in identifying MSM with P&S syphilis may exist, specifically among HIV-infected MSM, and those diagnosed in private health care settings. Strategies to address these gaps may include local guidelines and provider education to screen MSM more frequently than CDC currently recommends and regardless of HIV status or risk.