title: Validity of the Acti4 method for detection of physical activity types in free-living settings: comparison with video analysis.
abstract: This study examined the ability of the Acti4 software for identifying physical activity types from accelerometers during free-living with different levels of movement complexity compared with video observations. Nineteen aircraft cabin cleaners with ActiGraph GT3X+ accelerometer at the thigh and hip performed one semi-standardised and two non-standardised sessions (outside and inside aircraft) with different levels of movement complexity during working hours. The sensitivity for identifying different activity types was 75.4-99.4% for the semi-standardised session, 54.6-98.5% outside the aircraft and 49.9-90.2% inside the aircraft. The specificity was above 90% for all activities, except 'moving' inside the aircraft. These findings indicate that Acti4 provides good estimates of time spent in different activity types during semi-standardised conditions, and for sitting, standing and walking during non-standardised conditions with normal level of movement complexity. The Acti4 software may be a useful tool for researchers and practitioners in the field of ergonomics, occupational and public health. Practitioner Summary: Being inexpensive, small, water-resistant and without wires, the ActiGraph GT3X+ by applying the Acti4 software may be a useful tool for long-term field measurements of physical activity types for researchers and practitioners in the field of ergonomics, occupational and public health.
authors.affiliation: a National Research Centre for the Working Environment , Copenhagen , Denmark.
authors.forename: Ingunn
authors.initials: I
authors.lastname: Stemland
authors.forename: Jørgen
authors.initials: J
authors.lastname: Ingebrigtsen
authors.forename: Caroline S
authors.initials: CS
authors.lastname: Christiansen
authors.forename: Bente R
authors.initials: BR
authors.lastname: Jensen
authors.forename: Christiana
authors.initials: C
authors.lastname: Hanisch
authors.forename: Jørgen
authors.initials: J
authors.lastname: Skotte
authors.forename: Andreas
authors.initials: A
authors.lastname: Holtermann
mesh_terms: D061725:Accelerometry; D056044:Actigraphy; D000328:Adult; D000401:Aircraft; D015444:Exercise; D005260:Female; D006796:Household Work; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement; D011187:Posture; D015203:Reproducibility of Results; D014741:Video Recording
keywords: Acti4; ActiGraph; accelerometry; occupational; validation