Use of a Perceptual Evaluation Instrument to Assess the Effects of Infant Orthopedics on the Speech of Toddlers with Cleft Lip and Palate

Objective To investigate the effects of infant orthopedics (IO) administered in the first year of life on the speech characteristics of 2.5-year-old children with complete unilateral cleft lip and palate (UCLP) using a perceptual evaluation instrument with equal-appearing interval (EAI) scales. Design In a prospective randomized clinical trial (Dutchcleft), two groups of children with complete UCLP were followed longitudinally. One group received IO based on a modified Zurich approach (IO group), and the other group did not (non-IO group). The appliance was used until soft palate closure at age 12 months. Hard palate closure is delayed until 9 years of age. Participants Three groups of 2.5-year-old toddlers participated in this investigation: 10 IO, 10 non-IO, and 8 noncleft controls matched for age and socioeconomic status. Method Five trained listeners assessed the children's speech in a blinded perceptual rating procedure. They judged 13 specific speech characteristics and indicated their total impression of speech on EAI scales. Results The reliability and consistency of 11 of the rating scales was good. The intelligibility rating scale was the single speech characteristic that distinguished the IO group from the non-IO group; the IO group was judged to be superior. The cleft groups differed from the noncleft group on 9 of the 11 scales. Conclusions Evaluation of speech by means of the present newly developed perceptual rating instrument showed that the IO group obtained significantly higher ratings for intelligibility than the non-IO group. The groups did not differ regarding any of the other speech aspects.