Purpose: The aim was to investigate, describe and analyse speech characteristics, intelligibility, orofacial function and co-existing neurodevelopmental symptoms in children with SSD of unknown origin, persisting after six years of age.Method: The study included 61 children with SSD (6-17 years) of unknown origin, referred for a speech and oral motor examination. The severity of SSD was estimated using Percentage Consonants Correct (PCC) and Percentage Vowels Correct (PVC) and assessments of resonance based on Swedish Articulation and Nasality Test (SVANTE). Orofacial function was screened using the Nordic Orofacial Test-Screening (NOT-S). Parents completed the Intelligibility in Context Scale (ICS) and a questionnaire including questions about heredity, medical and neurodevelopmental conditions, and speech development.Result: SSD varied according to PCC (8-95%) and PVC (55-100%) measurements. Percentages of co-occurring disorders included: 51% resonance deviations, 90% intelligibility issues, and 87% orofacial difficulties. The most affected orofacial domains were "Chewing and swallowing" (41%), "Masticatory muscles and jaw function" (38%) and "Sensory function" (38%). The majority (64%) had co-existing dysfunctions relating to general motor and neurodevelopmental disorders.Conclusion: Children with persistent SSD are at risk for orofacial dysfunction, general motor difficulties and other neurodevelopmental disorders and therefore should be screened for co-occurring disorders.
Keywords: ESSENCE; PCC; PVC; intelligibility; orofacial function; speech sound disorder.