RT Journal Article SR Electronic T1 Thigh-worn accelerometry for measuring movement and posture across the 24-hour cycle: a scoping review and expert statement JF BMJ Open Sport & Exercise Medicine JO BMJ OPEN SP EX MED FD BMJ Publishing Group Ltd SP e000874 DO 10.1136/bmjsem-2020-000874 VO 6 IS 1 A1 Matthew L Stevens A1 Nidhi Gupta A1 Elif Inan Eroglu A1 Patrick Joseph Crowley A1 Barbaros Eroglu A1 Adrian Bauman A1 Malcolm Granat A1 Leon Straker A1 Peter Palm A1 Sari Stenholm A1 Mette Aadahl A1 Paul Mork A1 Sebastien Chastin A1 Vegar Rangul A1 Mark Hamer A1 Annemarie Koster A1 Andreas Holtermann A1 Emmanuel Stamatakis YR 2020 UL http://bmjopensem.bmj.com/content/6/1/e000874.abstract AB Introduction The Prospective Physical Activity Sitting and Sleep consortium (ProPASS) is an international collaboration platform committed to harmonise thigh-worn accelerometry data. The aim of this paper is to (1) outline observational thigh-worn accelerometry studies and (2) summarise key strategic directions arising from the inaugural ProPASS meeting.Methods (1) We performed a systematic scoping review for observational studies of thigh-worn triaxial accelerometers in free-living adults (n≥100, 24 hours monitoring protocols). (2)Attendees of the inaugural ProPASS meeting were sent a survey focused on areas related to developing ProPASS: important terminology (Q1); accelerometry constructs (Q2); advantages and distinct contribution of the consortium (Q3); data pooling and harmonisation (Q4); data access and sharing (Q5 and Q6).Results (1) Eighty eligible articles were identified (22 primary studies; n~17 685). The accelerometers used most often were the ActivPAL3 and ActiGraph GT3X. The most commonly collected health outcomes were cardiometabolic and musculoskeletal. (2) None of the survey questions elicited the predefined 60% agreement. Survey responses recommended that ProPASS: use the term physical behaviour or movement behaviour rather than ‘physical activity’ for the data we are collecting (Q1); make only minor changes to ProPASS’s accelerometry construct (Q2); prioritise developing standardised protocols/tools (Q4); facilitate flexible methods of data sharing and access (Q5 and Q6).Conclusions Thigh-worn accelerometry is an emerging method of capturing movement and posture across the 24 hours cycle. In 2020, the literature is limited to 22 primary studies from high-income western countries. This work identified ProPASS’s strategic directions—indicating areas where ProPASS can most benefit the field of research: use of clear terminology, refinement of the measured construct, standardised protocols/tools and flexible data sharing.