Background: Pharmaceutical industry-sponsored research has been shown to be biased toward the reporting of positive results. Frequent involvement of industry in studies addressing the addition of long-acting beta-agonist (LABA) to inhaled corticosteroid (ICS) therapy and the debates regarding the effectiveness and safety of combination treatment warrant an assessment of potential publication bias in this area. Objectives: To describe the frequency of industry involvement in trials on LABA/ICS; the direction of results for primary outcomes according to industry involvement; and the results emphasized in the conclusions. Methods: A systematic review of RCTs comparing LABA/ICS combination therapy with ICS monotherapy in adults with chronic asthma was conducted. Data concerning industry sponsorship, drug comparison, primary clinical outcomes, statistical results and authors’ conclusions were collected. Critical appraisal was conducted using the Jadad scale and assessment of allocation concealment, and the Cochrane Collaboration’s risk of bias tool. Results: Of 91 included studies (median year of publication 2005, range 1994 to 2008), 86 (95%) reported having pharmaceutical funding or at least one author affiliated with industry. Five trials were not industry-sponsored. Industry-reported trials without associated full publications comprised 25 (26%) of the reports. The remaining studies were published as journal articles. Companies represented in the studies were GlaxoSmithKline (57), AstraZeneca (22), Novartis (4) and AstraDraco (1). The following analyses are underway and results will be presented: types of industry involvement, proportion of positive and negative findings, direction of results by sponsorship, comparison of authors’ conclusions with results, and assessment of overstatement of claims. Conclusions: The results have implications for the conduct and interpretation of systematic reviews of studies that involve pharmaceutical-industry sponsorship and for the transparent reporting of study sponsorship.