Interventions versus comparators (included reviews; the number of studies with total participants)	Care setting	Relative effect (RR, 95% CI)	Anticipated absolute effect (95% CI)			Certainty of evidence	Interpretation of findings
			Risk with comparators	Risk with interventions	Difference
Proportion of participants with pressure ulcers completely healed
Alternating pressure (active) air surfaces versus foam surfaces (Shi 2021e; 2 RCTs with 132 participants)	Acute and long‐term care setting	Two studies reported this outcome: one study reported analysable data and the RR was 0.97 (95% CI 0.26 to 3.58); another study stated that the analysis of covariance showed no statistically significant difference in the healing of pressure ulcers between alternating pressure (active) air surfaces versus foam surfaces.	No pooling	No pooling	No pooling	⊕⊝⊝⊝ VERY LOW (downgraded twice for high risk of bias and twice for substantial imprecision)	It is uncertain if there is a difference in the proportion of participants with healed pressure ulcers between alternating pressure (active) air surfaces and foam surfaces.
Reactive air surfaces versus foam surfaces (Shi 2021e; 2 RCTs with 156 participants)	Acute and long‐term care setting	RR 1.32, 0.96 to 1.80	442 per 1000	583 per 1000 (424 to 795)	141 more per 1000 (18 fewer to 353 more)	⊕⊕⊝⊝ LOW (downgraded twice for imprecision)	It is unclear if there is a difference in the proportion of participants with pressure ulcers completely healed between reactive air surfaces and foam surfaces.
Foam surfaces versus reactive water surfaces (Shi 2021e; one RCT with 68 participants)	Long‐term care setting	RR 0.93, 0.61 to 1.42	481 per 1000	447 per 1000 (293 to 683)	37 fewer per 1000 (191 fewer to 199 more)	⊕⊝⊝⊝ VERY LOW (downgraded twice for risk of bias, and twice for imprecision).	It is uncertain if there is a difference in the proportion of participants with healed pressure ulcers between foam surfaces and reactive water surfaces.
Alternating pressure (active) air surfaces compared with the another type of alternating pressure (active) air surface (Shi 2021e; McGinnis 2014; 3 RCTs with 73 participants)	Acute and long‐term care setting	All studies reported no statistical difference between Nimbus alternating pressure air systems and Pegasus systems for improvement or healing of sacral pressure sores; no significant difference when using either mattress system in the number of heel ulcers healed (RR 1.49; 95% CI 0.90 to 2.45).	No pooling	No pooling	No pooling	⊕⊝⊝⊝ VERY LOW (downgraded once for risk of bias and twice for imprecision).	It is unclear if there is a difference in the proportion of participants with pressure ulcers completely healed between different types of alternating pressure (active) air surfaces (Nimbus vs. Pegasus).
Reactive gel surfaces versus undefined reactive surfaces (Aiartex; Shi 2021e; one RCT with 72 participants)	Long‐term care setting	RR 1.58, 0.41 to 6.11	86 per 1000	136 per 1000 (35 to 525)	50 more 1000 (51 fewer to 439 more)	⊕⊝⊝⊝ VERY LOW (downgraded twice for risk of bias and twice for imprecision).	It is uncertain if there is a difference in the proportions of participants with pressure ulcers completely healed between people using reactive gel surfaces and those using undefined reactive surfaces.
Time to complete pressure ulcer healing
Reactive air surfaces versus foam surfaces (Shi 2021e; 1 RCT with 84 participants)	Long‐term care setting	HR 2.66, 1.34 to 5.17	463 per 1000	809 per 1000 (566 to 960)	346 more per 1000 (103 more to 497 more)	⊕⊕⊝⊝ LOW (downgraded twice for imprecision)	People using reactive air surfaces may be more likely to have healed pressure ulcers compared with people using foam surfaces.
Support surface‐associated patient comfort
Alternating pressure (active) air surfaces versus foam surfaces (Shi 2021e; one RCT with 39 participants)	Acute care setting	‐	The mean support surface‐associated patient comfort was 0.	‐	MD 0.4 higher (0.42 lower to 1.22 higher)	⊕⊝⊝⊝ VERY LOW (downgraded twice for high risk of bias and once for imprecision)	It is uncertain whether there is any difference between alternating pressure (active) air surfaces and foam surfaces in patient comfort responses.
Reactive air surfaces versus foam surfaces (Shi 2021e; one RCT with 72 participants)	Acute care setting	One study reported this outcome as the number of participants having changes in comfort from baseline and reported that 8 participants using reactive air surfaces had increased comfort, 4 had no change, and 1 had decreased comfort; whilst 3 participants using foam surfaces had increased comfort, 4 had no change and 6 reported decreased comfort (P value = 0.04).	No pooling	No pooling	No pooling	⊕⊝⊝⊝ VERY LOW (downgraded twice for risk of bias and twice for substantial imprecision)	We are uncertain whether there is any difference between reactive air surfaces and foam surfaces in patient comfort responses.
Alternating pressure (active) air surfaces compared with another type of alternating pressure (active) air surface (Shi 2021e; McGinnis 2014; 4 RCTs with 256 participants)	Acute and long‐term care setting	Two small studies reported a statistical significance favouring Nimbus system whilst two larger studies reported no significance.	No pooling	No pooling	No pooling	⊕⊝⊝⊝ VERY LOW (downgraded once for risk of bias, once for heterogeneity and once for imprecision)	It is uncertain if there is a difference in patient comfort responses between different types of alternating pressure (active) air surfaces (Nimbus vs Pegasus).
Reactive air surfaces versus undefined 'standard hospital surfaces' (Shi 2021e; one RCT with 40 participants)	Acute care setting	The study reported this outcome defined as self‐rated participant satisfaction measured using an 8‐item scale with a totality of 11 points ranging from 'total dissatisfaction' to 'complete satisfaction'. In total, 18 of 40 participants responded on the scale. No data analysis reported.	No pooling	No pooling	No pooling	⊕⊝⊝⊝ VERY LOW (downgraded twice for risk of bias, and once for imprecision)	It is uncertain if there is a difference in patient comfort responses between these support surfaces.
Reactive gel surfaces versus undefined reactive surfaces (Aiartex; Shi 2021e; one RCT with 72 participants)	Long‐term care setting	18 participants using reactive gel surfaces responded with 'Poor', 12 with 'Fair', six with 'Good', and one with 'Excellent', whilst 8 participants using the undefined reactive surfaces responded with 'Poor', 13 with 'Fair', 10 with 'Good', and 4 with 'Excellent'.	No pooling	No pooling	No pooling	⊕⊝⊝⊝ VERY LOW (downgraded twice for risk of bias, and once for imprecision)	It is uncertain if there is a difference in patient comfort responses between these support surfaces.
All reported adverse events
Alternating pressure (active) air surfaces versus foam surfaces (Shi 2021e; one RCT with 49 participants)	Acute care setting	One study (49 participants) reported there were no major adverse events that could be attributed to the support surfaces used.	No pooling	No pooling	No pooling	⊕⊝⊝⊝ VERY LOW (downgraded twice for risk of bias and twice for substantial inconsistency).	It is uncertain if there is a difference in adverse events between alternating pressure (active) air surfaces and foam surfaces.
Foam surfaces versus reactive water surfaces (Shi 2021e; one RCT with 120 participants)	Long‐term care setting	One study reported this outcome, defined as the percentages of participants with one or more of the following types of adverse events: eczema, maceration, and pain.	No pooling	No pooling	No pooling	⊕⊝⊝⊝ VERY LOW (downgraded once for risk of bias and twice for imprecision).	It is uncertain if there is any difference in all reported adverse events between alternating pressure (active) air surfaces applied on both operating tables and hospital beds and reactive gel surfaces used on operating tables followed by foam surfaces applied on hospital beds.
Reactive air surfaces versus foam surfaces (Shi 2021e; two studies with 156 participants)	Acute care setting	Two studies (156 participants) reported this outcome and both did not clearly suggest any difference in adverse events.	No pooling	No pooling	No pooling	⊕⊕⊝⊝ LOW (downgraded once for imprecision and once for indirectness)	It is unclear if there is a difference in adverse events between reactive air surfaces and foam surfaces.
Alternating pressure (active) air surfaces compared with the another type of alternating pressure (active) air surfaces (Shi 2021e; McGinnis 2014; 4 RCTs with 256 participants)	Acute and long‐term care setting	The studies largely reported death data but did not state if there were other adverse events and outcome data were not pooled.	No pooling	No pooling	No pooling	⊕⊝⊝⊝ VERY LOW (downgraded once for risk of bias, once for imprecision and once for indirectness)	It is uncertain if there is a difference in adverse events between different types of alternating pressure (active) air surface.
Reactive air surfaces versus undefined 'standard hospital surfaces' (Shi 2021e; two RCTs with 152 participants)	Acute and long‐term care setting	We did not pool these data as the definitions of adverse events varied between studies.	No pooling	No pooling	No pooling	⊕⊝⊝⊝ VERY LOW (downgraded once for risk of bias, and twice for inconsistency)	It is uncertain if there is any difference in adverse events between reactive air surfaces and standard hospital surfaces.
Reactive gel surfaces versus undefined reactive surfaces (Aiartex; Shi 2021e; one RCT with 72 participants)	Long‐term care setting	We did not pool these data as the definitions of adverse events varied between studies.	No pooling	No pooling	No pooling	⊕⊝⊝⊝ VERY LOW (downgraded twice for risk of bias, and once for imprecision)	It is uncertain if there is any difference in adverse events between reactive gel surfaces and undefined reactive surfaces.
Cost‐effectiveness
Reactive air surfaces compared with foam surfaces (Shi 2021e; one RCT with 87 participants)	Long‐term care setting	One study reported the extra cost due to the use of reactive air surfaces, compared with foam surfaces, divided by the ulcer‐free days and suggested that people using reactive air surfaces may cost an extra 26 US dollars for every ulcer‐free day in the first year of use.	Not applicable	Not applicable	Not applicable	⊕⊕⊝⊝ LOW (downgraded twice for imprecision)	Compared with foam surfaces, reactive air surfaces may cost an extra 26 US dollars for every ulcer‐free day in the first year of use in long‐term care settings.