Alkhajah 2012.

Methods	Study design: controlled before‐and‐after trial Study duration: 3 months Dropout: 6% of all participants (0 to 18 in intervention group and 2 to 15 in control group); no specific information provided about participants with baseline musculoskeletal symptoms Location: Australia Recruitment: 2 academic institutions in Brisbane; to reduce contamination, participants in the comparison group were separated from intervention participants by at least 1 building level
Participants	Population: office workers Intervention group: 18 participants (total) with 0 to 7 participants with baseline pain Control group: 15 participants (total) with 0 to 4 participants with baseline pain Included criteria: between 20 and 65 years of age with a non‐adjustable workstation and a desktop computer Excluded criteria: non‐ambulatory, pregnant at baseline, working less than 0.5 full‐time equivalent, planned relocation to another work site within 3 months Baseline characteristics: imbalance in the proportion of participants in intervention and control groups that reported baseline musculoskeletal symptoms
Interventions	Intervention Description of intervention: installation of a sit‐stand workstation; brief verbal training and ergonomic information provided. Written instructions were also provided Duration of intervention: 3 months Intensity of intervention: not stated Control Description of intervention: maintained normal work duties Duration of intervention: 3 months Intensity of intervention: not stated
Outcomes	Outcome name, measurement tool, body region Musculoskeletal health Standardised Nordic Questionnaire for 9 body regions ‐ neck, shoulder, upper back, elbow, wrist, lower back, hip, knee, and ankle ‐ over last week and last 3 months Workplace sitting/standing/stepping time and sit‐stand transitions Measured by activPAL3 accelerometer/inclinometer device Physiological outcomes BMI, glucose, cholesterol Other health outcomes Fatigue, eye strain, self‐rated work performance, headaches, digestion, sleep problems, absenteeism
Identification
Notes	Sponsorship source: nil relevant reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Counfounding CBA	High risk	Quote: "the sample is not widely representative of workplaces and workers, and some confounding is possible. Further, models adjusted for baseline levels but not for other potential confounders because of insuffıcient sample size" Judgement comment: due to the small sample size in this study, adjustment for potential confounders was not possible
Selection Bias CBA	Low risk	Judgement comment: intervention and control participants were recruited from the same organisation and over the same time period
Blinding of participants and personnel	High risk	Judgement comment: due to the nature of the intervention of a sit‐stand workstation provided, it would not have been possible to blind researchers or participants from the intervention
Blinding of outcome assessment	Unclear risk	Judgement comment: in this study, musculoskeletal outcomes were a secondary outcome, so it is unclear whether the fact that participants were not blinded to the intervention would contribute to bias in self‐reporting of musculoskeletal outcomes
Incomplete outcome data	Low risk	Judgement comment: only 1 participant in the control group was excluded from analyses due to monitor malfunction
Selective reporting	Unclear risk	Judgement comment: all outcomes were reported in the paper, but there was no published protocol for the study, so it is not possible to determine if additional outcomes were proposed that were not reported
Baseline imbalance	High risk	Judgement comment: there were considerable differences in baseline symptoms for some body regions (e.g. neck, shoulder)