Barone 2017.

Study characteristics
Methods	Study design: Randomised controlled trial Study grouping: Sit Less (sedentary behaviour intervention), Get Active (control physical activity intervention) Randomisation method: Participants were randomly assigned to 1 of the 2 intervention groups with a 1:1 ratio. Randomisation was stratified by sex and cohabitation. Cohabiting (e.g. married) participants were randomised at the level of the couple. Assessment: Assessments were performed at baseline and 12 weeks. Objective activity was measured by a blinded, SenseWearPro armband (SWA) that did not provide feedback. Sedentary behaviour was assessed by a 6‐item questionnaire in addition to SWA. The questionnaire assessed usual time spent in 6 sedentary activities (e.g. watching TV, using a computer for work or recreation, riding in a car) separately for weekdays and weekends. Physical function was assessed with a 400‐metre walk test and Short Physical Performance Battery (SPPB). Quality of life was assessed with the 36‐item Short Form Health Survey (SF‐36; Walters, Munro, & Brazier 2001). Depressive symptoms were evaluated using the Center for Epidemiological Studies Depression Scale (CES‐D). Blood pressure was averaged over 2 consistent measures (differences of < 10 mmHg in systolic blood pressure and < 6 mmHg diastolic blood pressure) using a Dinamap automated blood pressure system after a 5‐minute rest period. Operational definition of sedentary time: Total sedentary time was calculated as the sum of “awake” minutes for which energy expenditure was ≤ 1.5 METs and converted to hours/day.
Participants	Baseline characteristics Sit Less Age: 68.5 (6.7) years Gender: 26% male Race: 95% white BMI: 28.3 (6.3) Education: 79% above bachelor degree N = 19 Get Active Age: 67.3 (6.5) years Gender: 32% male Race: 74% white BMI: 28.9 (4.8) Education: 84% above bachelor degree N = 19 Inclusion criteria: Eligibility criteria included age ≥ 60 years old, < 60 min per week of self‐reported moderate to vigorous physical activity (MVPA), ability to complete a 400‐metre walk test without an assistive device, ability to provide medical clearance from a physician to participate in the study, and access to a smartphone with Bluetooth. Exclusion criteria: A recent cardiovascular event (< 6 months), recent use of psychotropic medications or other treatment for psychological issues (< 6 months), any comorbid condition that limited participation in exercise (e.g. severe arthritis, current treatment for cancer), or self‐report of > 3 alcoholic beverages per day
Interventions	Intervention characteristics 12‐week intervention in which both groups received a combination of individual, in‐person, and phone consultations with an exercise physiologist coupled with the use of the BodyMedia SWA and interface on their personal smartphone. In‐person visits (30 to 60 min) occurred weekly during weeks 1 to 4. During weeks 5 to 12, in‐person visits were biweekly and alternated with biweekly scripted phone calls lasting approximately 10 min with the interventionist. The Sit Less group had a goal to reduce sedentary time by 1 h each day. The Get Active group had a goal to reach 150 min of MVPA each week, accumulated in bouts of ≥ 10 min. Participants were able to see feedback from the activity tracker for time spent in the target behaviour.
Outcomes	Primary outcomes Sedentary time (objectively measured) Outcome type: Continuous outcome Reporting: Fully reported Unit of measure: min/day Direction: Lower is better Secondary outcomes Systolic blood pressure Outcome type: Continuous outcome Reporting: Fully reported Unit of measure: mmHg Direction: Lower is better Diastolic blood pressure Outcome type: Continuous outcome Reporting: Fully reported Unit of measure: mmHg Direction: Lower is better 400‐metre walk Outcome type: Continuous outcome Reporting: Fully reported Unit of measure: min Direction: Lower is better Gait speed Outcome type: Continuous outcome Reporting: Fully reported Unit of measure: m/s Direction: Lower is better Short Physical Performance Battery (SPPB) Outcome type: Continuous outcome Reporting: Fully reported Direction: Higher is better
Identification	Sponsorship source: This research was funded by the University of Pittsburgh Claude D. Pepper Center Program (P30 AG024827). Country: USA Setting: Community Comments: This study compares intervening to reduce sedentary behaviour versus intervening to increase MVPA. Sitting reduction intervention did not change physical activity, and physical activity intervention did not change sitting. However, sitting intervention significantly increased physical function 0.5 on the SPPB (only the chair stand subscale changed 0.42 chair stands). The physical activity intervention did not change physical function. Author's name: Bethany Barone Gibbs Institution: Pittsburgh University Email: bbarone@pitt.edu Address: Department of Health and Physical Activity, Physical Activity and Weight Management Research Center, University of Pittsburgh, 32 Oak Hill Court, Room 205, Pittsburgh, PA 15261, USA
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	No information describing the sequence generation despite clear description of the stratification of the randomisation
Allocation concealment (selection bias)	High risk	Allocation was 1:1 between groups, but no information is provided regarding how this was achieved.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Participants were assigned to a Sit Less or Get Active arm, and interventionists were assigned exclusively to 1 arm of the study.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Use of device‐based measure, but no information about blinding of assessors
Incomplete outcome data (attrition bias) All outcomes	Low risk	Reports that there were no missing data with clear description
Selective reporting (reporting bias)	Unclear risk	Not all outcomes listed in the methods section are presented clearly in the results section.
Other bias	Low risk	None