Ann Intern Med -- Lanzkron et al. 0 (2008): 0000605-200806170-00221 Figure 1

Please click here to check whether you must obtain permission to reproduce this image.

Figure 1. Study flow diagram.

*The evidence report provides details of the search strategies (7). ${dagger}$ The reasons for exclusion exceed the total number of studies because reviewers could enter multiple reasons for exclusion. ${ddagger}$ 89 studies were not included in this review because they included children or infants only or examined barriers only. Toxicity and efficacy studies in sickle cell disease overlap.