Psychometric properties of the Viking Speech Scale—Turkish version for children with cerebral palsy aged 4–18 years based on live and video‐based observation
Authors: Seyhan‐Biyik Kübra , Esen‐AydinlI Fatma , Sel Sinem Asena , Incebay Önal , Özcebe Esra , Kerem‐Günel Mintaze , Anlar Fatma Banu , Pennington Lindsay 
Published: November 2022

Background

Speech is the most common method of communication. Video‐based clinical communication evaluation is a requirement for children with speech–language impairments living in rural areas, and those who have limited mobility.

Aims

To determine the validity and reliability of the Turkish version of the Viking Speech Scale (VSS‐T) via live and video‐based observation for children with cerebral palsy (CP) aged 4–18 years.

Methods & Procedures

A total of 142 children (mean age 8.18 ± 3.98 years; 68 female) with CP were included in this study. Their motor, communication, visual and eating–drinking function levels and comorbidities (dental, swallowing, cognitive impairments and epilepsy) were recorded. The Intelligibility in Context Scale (ICS), the Pediatric Evaluation of Disability Inventory—Social Function (PEDI‐SF), and the Functional Independence Measure for Children—Communication (WeeFIM‐C) were assessed to examine the concurrent validity of the VSS‐T. The interrater reliability of the VSS‐T was analysed between parents, physical therapists, and speech and language therapists from live and video‐based observation. Intra‐rater reliability was calculated from ratings made from live and video‐based observations taken 3 weeks apart.

Outcomes & Results

The VSS‐T was strongly related to the ICS (r = –0.830), PEDI‐SF (r = –0.819), WeeFIM‐C (r = –0.643), other functional classifications (r > 0.432), and the comorbidities (Cramer's V > 0.284, p < 0.001). Good to excellent interrater reliability (κw ≥ 0.838) and intra‐rater reliability (intraclass correlation coefficient (ICC) = 0.848–0.995) were found between parents and therapists.

Conclusions & Implications

Speech and language therapists, physical therapists, and parents can use the VSS‐T as a valid and reliable classification system to describe speech intelligibility of 4–18‐year‐old children with CP. Both live and video‐based observations can be used to administer the VSS‐T.

What This Paper Adds

What is already known on the subject

The English version of the VSS has been shown to be a valid and reliable tool used to classify the speech of children with CP aged 4–13 years. The scale can be administered by means of live observation of the child or based on clinicians’ notes on the case by parents, SLTs, physiotherapists and paediatricians.

What this paper adds to existing knowledge

The VSS‐T is valid and reliable for children with CP aged 4–18 years. Video‐based observation is a suitable method for evaluating the VSS‐T levels. The VSS‐T has a moderate association with the CFCS.

What are the potential or actual clinical implications of this work?

The VSS‐T is a valid and reliable method of categorizing the severity of motor speech impairment for Turkish children with CP in clinical research studies, registry systems or epidemiological studies. Both experienced and inexperienced therapists can use either live or video‐based observation methods to administer the VSS‐T. This study extended the validity and reliability of the scale in children with CP aged up to 18 years. The VSS‐T is also associated with the Visual Functional Classification System (VFCS), which has been recently developed for describing the visual abilities of children with CP in daily life. In addition, the VSS‐T is associated with the presence of dental, swallowing, cognitive problems and epilepsy.