Cochrane 1990.

Study characteristics
Methods	Study design: RCT Total duration of study: 3 months Details of any run‐in period: 6 week run‐in period Number of study centres and location: Single site. Scotland. Study setting: Hospital Withdrawals: None documented Date of study: Not stated
Participants	Number recruited: Intervention group (18) Control group (18) Number completed: Intervention group (18) Control group (18) Mean (SD) age: Intervention group 27 (7) years. Control group 28 (8) years Age range: 16 to 40 years Gender (M/F): 14 male and 22 female participants Mean (SD) BMI: Not stated Severity of condition: Mild to moderate asthma Diagnostic criteria: Mild to moderate asthma was defined by a requirement for regular prophylactic treatment and reproducible airways obstruction when treatment was withdrawn. Baseline lung function: Mean (SD) % predicted postbronchodilator FEV1 Intervention Group 85 (16)% Control Group 89 (14)% Smoking history: All participants were non‐smokers. Asthma treatment: All participants were taking aerosolised sympathomimetic agents. 15 had also been prescribed inhaled sodium cromoglycate and 21 corticosteroid preparations for inhalation. 2 participants were dependent on long‐term oral steroids. Inclusion criteria: Not stated Exclusion criteria: Not stated
Interventions	Intervention: 3‐month medically supervised indoor aerobic training programme (30 min x 3 days per week aerobic training at 75% predicted maximum HR). Educational sessions designed to encourage a greater understanding and to improve self‐management of asthma as well as description of the training programme principles Comparison: Attendance at education sessions designed to encourage a greater understanding and to improve self‐management of asthma. Concomitant medications: All participants were taking aerosolised sympathomimetic agents. 15 had also been prescribed inhaled sodium cromoglycate and 21 corticosteroid preparations for inhalation. 2 participants were dependent on long‐term oral steroids. Excluded medications: None stated
Outcomes	Primary outcomes: No prespecified primary outcome, but the following were measured: Anthropometric characteristics. Spirometry. Provocative concentration of histamine causing a 20% fall in FEV1. Blood lipid profile. Incremental CPET (cycle ergometer): Oxygen consumption (VO2), Oxygen pulse, Breathlessness score (Borg), Blood lactate, Minute ventilation during submaximal exercise, Carbon dioxide production (VCO2), Dyspnoea index, Ventilatory anaerobic threshold. Secondary outcomes: No prespecified secondary outcomes Time points reported: Baseline and 3 months Data reported as endpoint rather than as change from baseline.
Notes	Funding: Allen and Hanburys Ltd provided a clinical research fellowship for the first author. The Chest, Heart and Stroke Association (Scottish branch) funded the training programme. Notable conflicts of interest: None stated Other: All participants were “free from any concomitant illness”. Alteration in treatment: During the study period, 9 of the 36 participants (6 from intervention group and 3 from control group) had their treatment altered. 7 were changed from inhaled sodium cromoglycate to an inhaled steroid, and 2 participants had the dose of inhaled steroid increased. Number of training sessions: The mean number (range) of training sessions undertaken by participants in the intervention group was 36 (19 to 42) (22 (8 to 42) hospital sessions and 14 (0 to 36) home sessions).
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Method of randomisation not specified. “The patients were then randomly allocated to either the training or the control group”
Allocation concealment (selection bias)	Unclear risk	Not stated whether allocation was concealed.
Blinding of participants and personnel (performance bias) Not subjectively reported outcomes	High risk	No mention of blinding.
Blinding of outcome assessment (detection bias) Not subjectively assessed outcomes	Unclear risk	No mention of blinding.
Incomplete outcome data (attrition bias) All outcomes	Low risk	No dropouts.
Selective reporting (reporting bias)	Unclear risk	Protocol presumably not published, given the age of the study.
Other bias	Unclear risk	“During the study period, nine of the 36 study subjects (six of those undergoing training and three of the control subjects) had their treatment altered.”