LAUSR

Purpose Speech-language pathologists' clinical decision making and consideration of eligibility for services rely on quality evidence, including information about consonant acquisition (developmental norms). The purpose of this review article is to describe the typical age and pattern of acquisition of English consonants by children in the United States. Method Data were identified from published journal articles and assessments reporting English consonant acquisition by typically developing children living in the United States. Sources were identified through searching 11 electronic databases, review articles, the Buros database, and contacting experts. Data describing studies, participants, methodology, and age of consonant acquisition were extracted. Results Fifteen studies (six articles and nine assessments) were included, reporting consonant acquisition of 18,907 children acquiring English in the United States. These cross-sectional studies primarily used single-word elicitation. Most consonants were acquired by 5;0 (years;months). The consonants /b, n, m, p, h, w, d/ were acquired by 2;0-2;11; /ɡ, k, f, t, ŋ, j/ were acquired by 3;0-3;11; /v, ʤ, s, ʧ, l, ʃ, z/ were acquired by 4;0-4;11; /ɹ, ð, ʒ/ were acquired by 5;0-5;11; and /θ/ was acquired by 6;0-6;11 (ordered by mean age of acquisition, 90% criterion). Variation was evident across studies resulting from different assessments, criteria, and cohorts of children. Conclusions These findings echo the cross-linguistic findings of McLeod and Crowe (2018) across 27 languages that children had acquired most consonants by 5;0. On average, all plosives, nasals, and glides were acquired by 3;11; all affricates were acquired by 4;11; all liquids were acquired by 5;11; and all fricatives were acquired by 6;11 (90% criterion). As speech-language pathologists apply this information to clinical decision making and eligibility decisions, synthesis of knowledge from multiple sources is recommended.