Measuring Children's Actual Exposure to Unhealthy Food Marketing in (and With) Digital Media: A Narrative Scoping Review.

This review aimed to identify and evaluate methods to measure children's actual exposure (marketing that actually reaches children) to food marketing in digital media. Monitoring actual marketing exposure in digital media is challenging. It is delivered via complex, data-driven, personalized systems to children's personal devices-so viewing this presents privacy and methodological challenges. Digital marketing monitoring therefore often instead assesses potential exposure (marketing that children are likely to encounter in their usual digital places). Yet, measuring actual exposure is essential for policy development, enforcement, and research. We searched for eligible articles published during 2000-2024 using free-text searches combined with database thesauruses in Academic Search Complete (EBSCOhost), Ovid Medline, CINAHL (EBSCOhost), PsycInfo (EBSCOhost), and Scopus. A horizon scan, gray literature search, and consultation with experts were also performed. Data extracted were (1) type of method and tools, (2) how the method captures data, (3) challenges and limitations, (4) researcher burden, (5) recruitment and retention, (6) privacy, and (7) food marketing definitions and nutrient profiling system applied. We identified 25 sources (reporting on 16 studies) and grouped these into 4 methods clusters, each with different attributes and limitations: screen capture, where participants' device screen is recorded while they use it; wearable cameras, which capture participants' exposure to all marketing across a day; screenshots of self-identified marketing captured by participants themselves; and automated extraction of paid advertising metadata using software installed on participants' devices. Screen capture is currently the optimal method. No identified method is straightforward: all carry a heavy data management and analysis load and involve trade-offs of validity, ease of use, privacy, and overall cost. Capturing children's screens with currently available tools is challenging, but the benefits are clear, as identifying children's actual exposure to harmful marketing in digital media is essential.