In this study the authors address the quality of abstracts reviewed during a systematic review. Their objective was to describe the proportion of abstracts that could not be coded and to explore factors associated with that outcome. Using an exploratory design, a database of titles uploaded for analysis was examined for clarity, type and year of publication, and abstract format. Of the 1851 references examined, 481 (26%) were coded as unclear. The inter-rater reliability Kappa score was 0.777. These abstracts were more likely to have been published prior to 2002 and did not use a structured format. Abstracts are an important tool in the systematic review process. Structured abstracts can reduce the time and costs associated with conducting a systematic review.