A six-centre international study of the outcome of treatment in patients with clefts of the lip and palate: the results of a cross-linguistic investigation of cleft palate speech.

Speech samples of 131 subjects with complete unilateral clefts of the lip and palate from six European cleft palate centres were analysed and assessed using a specifically designed phonetic framework. This framework focused on consonants that are "vulnerable" in speech associated with cleft palate and common to the five languages of the project. The methodology used and the results of the reliability study are reported. Consonant articulation, resonance, and voice quality are also evaluated. The results show good outcomes with regard to consonant articulation across the whole study group with common areas of minor difficulty across languages. The results for resonance were less good, with slight hypernasality in 20% of subjects. There were, however, few indications of seriously disordered speech. The detectable differences between centres match the findings of the Eurocleft Orthodontic Group particularly in regard to the ranking of the centres.