Sex differences in the speech sound development of young children

Past studies have demonstrated higher prevalence rates of speech sound disorders among male than female children, based on standardized articulation tests with sex-averaged norms. Here, we survey the most commonly used standardized articulation tests for properties (size, age range, sex) of their norming samples. Based on the articulation assessment with sex-specific norms across the longest age span, we investigate sex differences in raw error scores corresponding to key standard score bands. Of 12 tests of speech sound production, six provided separate norms for females and males, but only two, the Goldman-Fristoe Test of Articulation – Third Edition (GFTA-3) and the Khan-Lewis Phonological Assessment – Third Edition (KLPA-3) that is based on the same word productions and norming sample as the GFTA-3, provided sex-specific norms for the entire sampled age span from 2 years 0 months to 21 years 11 months. In the lowest range of the score distribution, 1 and 2 standard deviations below the mean, and up to ages up to 6 years, both the GFTA-3 and KLPA-3 showed a distinct articulation accuracy advantage for females. Whereas the causes for this discrepancy are not well understood, clear clinical implications emerge: When diagnosing children with speech sound disorders toward qualifying them for interventions, it is imperative to use sex-specific norms, as sex-averaged norms may lead to over-diagnosing boys and under-diagnosing girls. Similarly, more precise prevalence rates of speech sound disorders among females and males can be obtained from sex-specific norms than from sex-averaged norms.