Abstract: We did not identify any randomised controlled trials that evaluated the effectiveness of sleep positioning systems on hip migration. We did find two randomised cross-over trials that met the inclusion criteria in respect of secondary objectives relating to sleep quality and pain. Neither study reported any important difference between sleeping in sleep positioning systems and not for sleep patterns or sleep quality (two studies, 21 children, very low quality evidence) and pain (one study, 11 children, very low quality evidence). These were small studies with established users of sleep positioning systems and were judged to have high risk of bias. We found no eligible trials that explored the other secondary objectives (number or frequency of hip problems, quality of life of the child and family, physical functioning, and adverse effects). We found no randomised trials that evaluated the effectiveness of sleep positioning systems to reduce or prevent hip migration in children with cerebral palsy. Nor did we find any randomised trials that evaluated the effect of sleep positioning systems on the number or frequency of hip problems, quality of life of the child and family or on physical functioning. Limited data from two randomised trials, which evaluated the effectiveness of sleep positioning systems on sleep quality and pain for children with cerebral palsy, showed no significant differences in these aspects of health when children were using and not using a sleep positioning system. In order to inform clinical decision-making and the prescription of sleep positioning systems, more rigorous research is needed to determine effectiveness, cost-effectiveness, and the likelihood of adverse effects.

Plain-language summary: We carried out a comprehensive search for studies. The evidence is current to December 2014. No randomised controlled trials were found that evaluated the effectiveness of sleep positioning systems to reduce or prevent hip migration. Two small randomised controlled trials compared children's quality of sleep when they were using and not using their sleep positioning system. One of these studies also examined pain when sleeping in and out of a sleep positioning system. These were cross-over trials (see Cochrane Glossary). The children in these studies spent a few nights using their sleep positioning system and then a few nights not using it, or the other way round. The order in which they either used or did not use the equipment was randomised. Twenty-one children with cerebral palsy, aged between 5 and 16 years, who were used to sleeping in sleep positioning systems took part in the studies. One of the studies took place in a sleep laboratory and the other study took place in the children's homes. Neither study reported any differences in quality of sleep or pain whether using or not using their sleep positioning system. These results need to be interpreted cautiously due to the small numbers of children involved and the fact that the children who participated were already accustomed users of the equipment. There were also various weaknesses in the way the research was designed and reported. The quality of the current evidence regarding the effectiveness of sleep positioning systems for children with cerebral palsy is very low and more robust research is needed to help families and professionals make informed decisions about whether to use this intervention.