Malbrain 2010.

Study characteristics
Methods	Study objective: to compare pressure ulcer outcomes in medical intensive care unit (ICU) patients nursed on either a reactive mattress overlay (ROHO®, ROHO Inc, Belleville, IL, USA) or an active alternating pressure mattress (NIMBUS®3, ArjoHuntleigh, Luton Bedfordshire, UK) Study design: randomised controlled trial Study grouping: parallel group Duration of follow‐up: not specified; mean study duration reported 12.2 days (SD 5.5) in ROHO and 15 (14) in NIMBUS 3 Number of arms: 2 Single centre or multi‐site: single centre Study start date and end date: not described Setting: medical ICU of a hospital
Participants	Baseline characteristics Inclusion criteria: patients admitted to the ICU with a high pressure ulcer risk (Norton score ≤ 8) and requiring mechanical ventilation for an estimated duration of at least 5 days either (a) with intact skin or (b) with pressure ulcers on admission Exclusion criteria: refused to consent to the study; either of 2 mattresses unavailable for patients admitted Sex (M:F): 8:8 across groups; 5:3 in ROHO; 3:5 in NIMBUS 3 Age (years): mean 64.7 (SD 15.6) across groups; 71.6 (11.9) in ROHO overlay; 56.9 (16.3) in NIMBUS 3 mattress Baseline skin status: mean Norton score 7.2 (SD 0.7) across groups; 7 (0) in ROHO and 7.4 (1.1) in NIMBUS 3 Group difference: different age distributions between groups Total number of participants: n = 16 Unit of analysis: individuals Unit of randomisation (per patient): individuals
Interventions	Intervention characteristics ROHO dry floatation mattress overlay Description of interventions: the ROHO DRY FLOATATION mattress overlay (ROHO Inc, Belleville, IL, USA) ... a manually inflatable reactive low‐pressure mattress, overlaying a normal hospital mattress that moulds to the body surface in order to distribute the pressure over an area as large as possible. NPIAP S3I classification: non‐powered, reactive air surface Co‐interventions: Belgian consensus protocol for ulcer prevention and treatment (including 2‐hourly repositioning) Number of participants randomised: n = 8 Number of participants analysed: n = 8 assumed NIMBUS 3 mattress Description of interventions: a fully automatic active alternating pressure mattress replacement consisting of 20 individual cells (3 head, 8 torso, 4 leg and 5 heel) that alternatively inflate and deflate over a 10‐minute cycle repeatedly off‐loading the tissues. NPIAP S3I classification: powered, alternating pressure (active) air surface Co‐interventions: Belgian consensus protocol for ulcer prevention and treatment (including 2‐hourly repositioning) Number of participants randomised: n = 8 Number of participants analysed: n = 8 assumed
Outcomes	Proportion of participants developing a new pressure ulcer Outcome type: binary Time points: not specified Reporting: partially reported Measurement method (e.g. scale, self‐reporting): nurse/clinician‐rated ulcers using EPUAP system Definition (including ulcer stage): pressure ulcer incidence of stage 1 and incidence of stage 2 to 4 according to EPUAP system Dropouts: no missing data Notes (e.g. other results reported): 3 of 8 individuals (2 stage 3 or 4 and 1 stage 1) in ROHO and 2 of 8 individuals (both stage 1) in NIMBUS 3 Time to pressure ulcer development Reporting: not reported Support‐surface‐associated patient comfort Reporting: not reported All reported adverse events using allocated support surfaces Reporting: not reported Health‐related quality of life (HRQOL) Reporting: not reported Cost‐effectiveness Reporting: not reported Outcomes that are not considered in this review but reported in trials: Pressure ulcer healing outcome (reported but not extracted because patients with ulcers are not units of randomisation)
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Randomisation of patients to products was performed blinded by the insertion of equivalent numbers of labels written with 'active' or 'reactive' placed in identical sealed envelopes that were shuffled and placed in a box and drawn in sequence" Comment: low risk of bias because a simple randomisation was applied.
Allocation concealment (selection bias)	Unclear risk	Quote: "Randomisation of patients to products was performed blinded by the insertion of equivalent numbers of labels written with 'active' or 'reactive' placed in identical sealed envelopes that were shuffled and placed in a box and drawn in sequence. When a patient was admitted who fulfilled the inclusion criteria the next envelope was opened by a ward nurse and the patient was assigned to the mattress on the label" Comment: unclear risk of bias because it is unclear if the envelopes were opaque.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Outcome group: primary outcome Comment: no information provided.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Outcome group: primary outcome Quote: "skin overlying bony prominences was thoroughly inspected in appropriate light by the ICU nurse; the outcome was documented ... any PU’s were assessed independently by the study nurse and study doctor, using ... pressure ulcer scale for healing [PUSH] tool ... category according to EPUAP definitions" Comment: unclear risk of bias because blinding of outcome assessment is not reported.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Outcome group: primary outcome Comment: low risk of bias because it is likely there were no missing data.
Selective reporting (reporting bias)	Low risk	Comment: the study protocol is not available but it is clear that the published reports include all expected outcomes, including those that were pre‐specified.
Other bias	Low risk	Comment: the study appears to be free of other sources of bias.