Study designs of evaluations included in the review
Controlled studies were eligible for inclusion in the review. Observational studies and cross-sectional studies were excluded.
Specific interventions included in the review
Studies that evaluated interventions to reduce SB in natural settings were eligible for inclusion. Multilevel interventions that included a reduction in SB component were included. Sedentary behaviour was defined as recreational screen time and did not include educational activities such as homework or reading. Some of the included studies were clinic-based (e.g. speciality clinics and primary care); others were population-based and included pre-school, elementary school and middle school settings. The studies used a variety of interventions (details were reported) and some had active control interventions. The duration of the interventions ranged from 20 minutes to 4 years.
Participants included in the review
Studies of children and adolescents were eligible for inclusion in the review. Some of the included studies were in children at risk or obese children; other studies targeted all children regardless of baseline weight. Studies targeted children aged from pre-school to middle school.
Outcomes assessed in the review
Studies that assessed measures of SB or weight were eligible for inclusion. In most studies, SB measurements were based on self-report questionnaires. Weight measures included body mass index (BMI), BMI z-scores, changes in the percentage of overweight participants, body fat and triceps skin-fold measurements. The outcomes were measured post-intervention in most of the included studies.
How were decisions on the relevance of primary studies made?
Two reviewers independently selected the studies. A third author resolved any disagreements on inclusion.