The SOL formulas for converting SMOG readability scores between health education materials written in Spanish, English, and French

The SMOG formula is widely used to determine how easy written health educat ion materials are to read and comprehend. This study was conducted to asses s whether the SMOG formula, originally developed and tested in English, was also valid for texts written in Spanish and French. Readability scores fro m a sample of passages written in Spanish, English, and French were analyze d. Study results showed that the SMOG formula seemed to be consistent in me asuring readability in the three languages. However, SMOG scores varied fro m language to language. Two hypotheses are being laid out to explain these results. First, the SMOG equation is systematically biased for texts in Spa nish or French. Second, English is more readable than French, and French is more readable than Spanish. Under the assumption of a systematic bias in t he SMOG formula, the so-called SOL formulas are presented here to convert S MOG scores between Spanish, English, and French. In addition, a new scale f or grading reading difficulty is proposed based on SMOG scores obtained fro m classical literature. This is important to the extent that it will provid e Spanish speaking and French speaking health communicators with a readabil ity formula for preparing written materials appropriate to the level of com prehension of specific target audiences.