The Boder Test of Reading-Spelling Patterns (Boder & Jarrico, 1982) is a widely used method for screening and defining reading problems at the level of the word. In order to apply this method in another language, in this case French, criteria for determining what constitutes a good phonetic equivalent for a misspelled word are required. It is essential to know which errors differentiate good and poor readers since errors that are commonly made by good readers are not diagnostic. This paper reports guidelines which have been developed by analyzing spelling errors in a sample of good and poor French immersion readers. These criteria for good phonetic equivalents can be applied, along with the method outlined in the Boder test manual, and used as an assessment tool for screening decoding and encoding problems in French immersion children. When used in conjunction with the English test, the assessment provides bilingual comparisons and guidelines for remedial programming.