A study was conducted at Florissant Valley Community College (FVCC) to compare three standardized tests--the Iowa Silent Reading Test (ISRT), the Nelson-Denny Reading Test (NDRT), and the Stanford Diagnostic Reading Test (SDRT)--for use in assessing student reading skills. The study population of 402 students included 216 students who agreed to participate and 186 students enrolled in freshman English classes selected for testing. Of this group, 102 students completed the NDRT, Form E and the SDRT, Blue Level Form A; 184 completed the NDRT and the ISRT, Level 3 Form E; and 116 completed the NDRT only. At the end of the fall 1982 semester, course grades were obtained for the tested students. Predictive validity of the three tests was determined by computing Pearson product-moment correlation coefficients, and a stepwise regression analysis was completed to determine the most effective combination of variables for predicting academic performance. Study findings revealed that all three tests had adequate predictive validity, but that the ISRT's predictive validity was substantially greater than that of the SDRT or NDRT. The combination of the ISRT scores plus high school rank accounted for about 70% of the variance in semester grade point average and about 68% of the variance in reading-related course grades. (HB)