A number of tests have been developed for early screening of difficulties in learning to read. However, little research has compared their performance or their diagnostic abilities. Our study aims to evaluate 6 reading tests (Time2, LUM, words and pseudowords reading subtests from Evalec, the Batelem and a non standardized phonological decoding subtests) by using a standard French reading test (l'Alouette) as a reference test. ROC curves were used for: 1. evaluating and comparing tests based on sensitivity, specificity, weights of evidence and expected weights of evidence and 2. choosing optimal cut-off values. Results show that these tests have good overall performance but they differ in their diagnostic abilities. Strategies are proposed for effectively using these tests in a screening program for second grade children.