Use the "Tool for Assessing Risk of Bias" available in Higgins, J., Altman, D., Juni, P., & et al. (2011). The Cochrane Collaboration's tool for assessing risk of bias in randomized trials. British Medical Journal, 343 (d5928), 1-9. PMID: 22008217
Amarillo Reference: 806-414-9964
Lubbock Reference: 806-743-2200; ask for a reference librarian
Odessa/Permian Reference; 432-703-5030