Alkhajah 2012

Methods	Non‐random allocation by clusters: CBA Single‐blind Study duration: 3 months Dropout: 9% Location: Australia Recruitment: control group participants were recruited from locations separated from the intervention group participants by at least 1 building level
Participants	Population: employees in public health research centres within 2 academic institutions, aged 20‐65 years Intervention group: 18 participants Control group: 12 participants Demographics: BMI: intervention group 22.6 (SD 2.6) kg/m², control group 21.5 (SD 2.6) kg/m²
Interventions	Duration: 3 months Intervention: sit‐stand desk Control: sit‐desk
Outcomes	Outcome name, measurement time/tool (units of measurement) Changes in sitting/standing/stepping time (minutes/8‐hour workday) measured at 1 week and 3 months. Transitions in positions measured by activPAL3 accelerometer‐inclinometer and a self‐administered questionnaire Weight (kg), waist circumference (cm), hip circumference (cm), fat free mass (kg), fat mass (kg), fasting blood lipids (Total cholesterol/HDL/Triglycerides) (mmol/L) and glucose (mmol/L) at 1 week and 3 months Self‐reported health‐ and work‐related outcomes Musculoskeletal symptoms by anatomical regions Other health symptoms: eye strain, headaches, digestion problems, trouble walking, trouble sleeping, fatigue (scale 1‐5) Work‐related outcomes: ≥ 1 day off sick (last 3 months), work performance (scale 1‐10)
Notes	This study was funded by a University of Queensland Major Equipment and Infrastructure grant. Alkhajah was supported by a United Arab Emirates Ministry of Higher Education and Scientifıc Research Scholarship; Reeves was supported by a National Health and Medical Research Council (NHMRC) Early Career Fellowship; Eakin was supported by an NHMRC Senior Research Fellowship; Owen was supported by an NHMRC Senior Principal Research Fellowship; and Healy was supported by an NHMRC Early Career Fellowship. Authors reported no financial disclosures.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Randomisation was not done as participants in intervention and control groups were selected from different building locations.
Allocation concealment (selection bias)	High risk	Intervention and control groups were selected from two separate locations. However no information on allocation concealment.
Blinding of participants and personnel (performance bias) All outcomes	High risk	The intervention group had sit‐stand desks installed at their workplace and received verbal instruction on their use, as well as written instructions on the correct ergonomic posture for both sitting and standing and the importance of regular postural change throughout the day. The control group had no change in desks and participants were advised to maintain usual day‐to‐day activity. The participants were probably aware of their allocation. The authors do not report who gave the instructions to the intervention and control groups.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported
Incomplete outcome data (attrition bias) All outcomes	Low risk	Virtually no attrition: only one participant was missing from the control group because of a malfunctioning accelerometer‐inclinometer.
Selective reporting (reporting bias)	Low risk	All outcomes mentioned in the method section were reported. Study protocol was not available.
Baseline comparability/ imbalance	High risk	Baseline data for age and gender were similar. It seems probable that there were baseline imbalances in awareness and physical activity levels between intervention and control groups as participants to the intervention group were selected from an academic institution focused on sedentary behaviour research whereas participants in the control group were never involved in physical activity research.
Validity of outcome measure	Low risk	The accelerometer‐inclinometer is a valid instrument for the measurement of sitting time.