Methods	Parallel-group, multicentre study (40 centres in Canada) Jadad quality score = 4
Participants	Symptomatic asthmatic adults % ELIGIBLE OF SCREENED POPULATION: Not reported % RUN-IN PARTICIPANTS RANDOMISED: Not reported RANDOMISED: 237 (FP/SAL: 121; FP: 116) WITHDRAWALS: FP/SAL: 4; FP: 7 AGE mean: 37 GENDER (% male): 35 SEVERITY: Moderate BASELINE % PREDICTED FEV1 (mean): Not reported BASELINE DOSE OF ICS: 100 mcg/d FP ASTHMA DURATION: Not reported ATOPY (%): Not reported ELIGIBILITY CRITERIA: >= 12 years of age; symptomatic despite low doses of ICS (<= 500 mcg/d or equivalent of BUD) for less than 4 weeks (criterion for run-in phase - participants who met the above criterion but had been on ICS for longer bypassed the run-in phase); symptomatic at end of run-in phase (on low-dose FP) EXCLUSION CRITERIA: < 60% or > 90% predicted of PEF at visit 1
Interventions	LABA + ICS versus INCREASED dose of FP OUTCOMES - TIMING 12 weeks RUN-IN: 2 weeks DOSE OF ICS DURING RUN-IN: 100 mcg/d FP INTERVENTION PERIOD: 12 weeks TEST GROUP: Combination fluticasone and salmeterol 100/50 bid CONTROL GROUP: Fluticasone 250 mcg bid DEVICE: Metered dose inhaler NUMBER OF DEVICES: 1 COMPLIANCE: Not assessed CO-TREATMENT: prn SABA
Outcomes	PULMONARY FUNCTION TEST: am PEF*; pm PEF; FEV1 SYMPTOM SCORES: Not reported FUNCTIONAL STATUS: Not reported INFLAMMATORY MARKERS: Not reported ADVERSE EFFECTS: Reported WITHDRAWALS: Reported Primary outcome measure*
Notes	Unpublished full data-set available from http://www.ctr.gsk.co.uk Source of funding: GSK Confirmation of methodology and data: Not obtained User defined number: 1000
Risk of bias
Item	Authors’ judgement	Description
Adequate sequence generation?	Yes	See Appendix 3
Allocation concealment?	Yes	See Appendix 3
Blinding? All outcomes	Yes	Identical inhaler devices used
Incomplete outcome data addressed? All outcomes	Unclear	“The Intent-to-Treat (ITT) population was used for all analyses including demographic, efficacy, safety and health outcome endpoints. This population consisted of all subjects who entered the study and were randomised to treatment.”
Free of selective reporting?	Yes	Moderate exacerbations used as proxy for steroid-treated exacerbations (see Analysis 3.1)