Eligible studies were randomised controlled trials (RCTs) or clinical controlled trials (CCTs) that compared provision of playground markings, games equipment and/or physical structures with no intervention in preschoolers (two to five years old) and schoolchildren (five to 12 years old). The school was required not to have any structured activities in place during school playtime. Outcomes of interest were vigorous and/or moderate-to-vigorous physical activity measured objectively with heart rate monitors, pedometers and/or accelerometers.
Examples of included intervention components were: themed, shaped or colour-coded floor markings (playground markings); skipping ropes, flying discs, racquets (games equipment); and football goal posts, basketball hoops (physical structures). Most participants were schoolchildren aged between four and 11. There were similar numbers of boys and girls. Where reported, school playtime ranged between 16 minutes and 42 minutes. Heart rate monitors and accelerometers were the included outcome measures.
It appeared that more than one reviewer was involved in a study selection process based on reading the abstracts of papers. Disagreements were resolved by consensus.