BACKGROUND Postural drainage is used primarily in infants with cystic fibrosis from diagnosis up to the moment when they are mature enough to actively participate in self-administered treatments. However, there is a risk of gastroesophageal reflux associated with this technique. OBJECTIVE To compare the effects of standard postural drainage (greater (30° to 45° head-down tilt) and lesser (15° to 20° head-down tilt)) with modified postural drainage (greater (30º head-up tilt) or lesser (15º to 20º head-up tilt)) with regard to gastroesophageal reflux in infants and young children up to six years old with cystic fibrosis in terms of safety and efficacy. METHODS We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Cystic Fibrosis Trials Register. We also searched the reference lists of relevant articles and reviews. Additional searches were conducted on ClinicalTrials.gov and on the WHO International Clinical Trials Registry Platform for any planned, ongoing and unpublished studies.The date of the most recent literature searches: 20 January 2015. METHODS We included randomised controlled studies that compared two postural drainage regimens (standard and modified postural drainage) with regard to gastroesophageal reflux in infants and young children (up to and including six years old) with cystic fibrosis. METHODS Two review authors independently selected the studies to be included in the review, assessed their risk of bias and extracted data. RESULTS Two studies, including 40 participants, were eligible for inclusion in the review. The studies were different in terms of the age of participants, the angle of tilt, the reported outcomes, the number of sessions and the study duration. The following outcomes were measured: appearance or exacerbation of gastroesophageal reflux episodes; percentage of peripheral oxygen saturation; number of exacerbations of upper respiratory tract symptoms; number of days on antibiotics for acute exacerbations; chest X-ray scores; and pulmonary function tests. One study reported that postural drainage with a 20° head-down position did not appear to exacerbate gastroesophageal reflux. However, the majority of the reflux episodes reached the upper oesophagus. The second included study reported that modified postural drainage (30º head-up tilt) was associated with fewer number of gastroesophageal reflux episodes and fewer respiratory complications than standard postural drainage (30º head-down tilt). The included studies had an overall low risk of bias. Data were not able to be pooled by meta-analysis due to differences in the statistical presentation of the data. CONCLUSIONS The available evidence regarding the comparison between the two regimens of postural drainage is still weak due to the small number of included studies, the small number of participants assessed, the inability to perform any meta-analyses and some methodological issues with the studies. However, it may be inferred that the use of a postural regimen with a 30° head-up tilt is associated with a lower number of gastroesophageal reflux episodes and fewer respiratory complications in the long term. The 20º head-down postural drainage position was not found to be significantly different from the 20º head-up tilt modified position. Nevertheless, the fact that the majority of reflux episodes reached the upper oesophagus should make physiotherapists carefully consider their treatment strategy.