| Study | Reason for exclusion |
|---|---|
| Benditt 2009 | Not a randomized controlled trial. It is a review of the literature |
| Campbell 1986 | The study intervention (PEEP) was different from the intervention included in this review CPAP or bilevel NPPV compared to oxygen therapy) |
| Conti 2007 | Not a randomized controlled trial. It was a matched‐controlled study |
| Cypel 2014 | The study population was different from the population included in this review. This study evaluated different interventions during the intraoperative period and our study evaluated interventions in participants who developed acute respiratory insufficiency in the postoperative period |
| Delclaux 2000 | The study population was different from the population included in this review. They evaluated adults admitted with acute respiratory failure secondary to pulmonary oedema |
| Denehy 2001 | The intervention studied was different from that proposed in this review. They compared periodic mask CPAP with physiotherapy after abdominal surgery |
| Foster 2005 | Not a randomized controlled trial. It was a comment on Squadrone 2005 |
| Frangos 2005 | Not a randomized controlled trial. It was a comment on Squadrone 2005 |
| Jaber 2005 | Not a randomized controlled trial. It was a case series |
| Kiil 2003 | The study population was different from the population included in this review. The aim of this study was to investigate the haemodynamic effects of CPAP in the late postoperative period in the general surgical ward |
| Kindgen‐Milles 2000 | Not a randomized controlled trial. It was a case series |
| Lee 2011 | Not a randomized controlled trial. It was a retrospective study |
| Michelet 2006 | The study intervention was different from the intervention included in this review. Participants underwent invasive mechanical ventilation |
| Souza 2012 | The study intervention was different from the intervention included in this review. The authors evaluated the use of CPAP therapy during the pre‐operative period |
| Tarraza 2001 | Not a randomized controlled trial. It was a case series |
| Zhang 2015 | The study intervention (PEEP) was different from the intervention included in this review CPAP or bilevel NPPV compared to oxygen therapy) |
CPAP: continuous positive airway pressure; NPPV: noninvasive positive pressure ventilation;
PEEP: positive end‐expiratory pressure.