To provide timely and effective supports for students reading below grade level, schools require methods for quickly and accurately identifying those students in need. One method for identifying those students is through universal screening. Assessments such as oral reading fluency (ORF) and Maze reading comprehension are commonly used as screening assessments in middle grades. The current study examined ORF and Maze for evidence of bias across two subgroups known to be at increased risk for failure in reading: (a) students with learning disabilities and (b) students from low-income households. Data from 4,215 students in the sixth (n = 1,126), seventh (n = 1,361), and eighth grades (n = 1,728) were analyzed. Results indicate no significant differences in predictive validity for students from low-income households compared to students from middle and upper income households. For students with learning disabilities only 8th grade scores showed any evidence of bias compared to students without diagnosed disabilities. Implications and recommendations for future research are discussed.