Studies of any design, except case reports, that evaluated the effects of at least four weeks supervised exercise training on physical activity in patients with chronic obstructive pulmonary disease were eligible for inclusion. Physical activity had to be measured using activity monitors and be reported in absolute values such as steps or activity counts.
In included studies, the duration of supervised exercise training ranged from six weeks to six months; it was measured using various monitors. Control groups, where present, included a general exercise programme, counselling and pedometer in addition to exercise. Most of the participants were men (72%). The mean age of participants ranged from 62.5 to 69.3 years. Most participants had severe airflow obstruction with forced expiratory volume (FEV1) ranging from 36% to 52%, where reported. Body mass index ranged from 24kg/m2 to 30.8kg/m2, where reported.
The authors did not state how many reviewers selected studies for inclusion.