Study designs of evaluations included in the review
Randomised controlled trials (RCTs) were included.
Specific interventions included in the review
Breathing techniques including slow deep breathing, physiotherapy, respiratory muscle strengthening, and yoga breathing exercises. Comparisons were waiting list controls, standard treatment or no intervention.
Participants included in the review
Adults and children with asthma were included.
Outcomes assessed in the review
A range of outcomes were assessed by two different studies included in the reviews. These were: improvement in breathing measured using forced expiratory volume in one second (FEV1), peak expiratory flow rate (PER), symptoms score, inhaler use, lung volume and flow rates by body plethysmography, medication use, time spent on physical activities, maximum inspiratory lung volume (VLImax), residual volume, resistance (body plethysmography), and peak flow.
How were decisions on the relevance of primary studies made?
The author does not state how the papers were selected for the review, or how many of the reviewers performed the selection.