Gross motor function, functional skills and caregiver assistance in children with spastic cerebral palsy (CP) with and without cerebral visual impairment (CVI)

Reliability and validity of the Japanese version of the Visual Function Classification System for children with cerebral palsy

BACKGROUND

Children with cerebral palsy (CP) often experience visual dysfunction that affects motor function and activities of daily living, but no 'gold standard' classification of visual function has been established. In recent years, however, a valid and reliable Visual Function Classification System (VFCS) for children with CP has been developed.

AIMS

To examine the reliability and validity of the Japanese version of the VFCS in individuals with CP.

METHODS

The translation of the VFCS was performed according to international standards for the translation of measurements. We conducted questionnaires of professionals (three physicians, eight physical therapists, five occupational therapists, six speech-language-hearing therapists and a certified orthoptist) regarding the content validity of the Japanese version of the VFCS. For reliability and concurrent validity, 148 individuals with CP were classified twice by professionals using the Japanese version of the VFCS, Gross Motor Function Classification System (GMFCS), Manual Ability Classification System (MACS), Communication Function Classification System (CFCS) and Eating and Drinking Ability Classification System (EDACS), with several weeks between each evaluation.

RESULTS

The content validity of the Japanese version of the VFCS almost met the criteria set. The percentage of positive and neutral opinions given by the professionals with regard to the four items ranged from 74% to 92%. The intra-rater reliability was 0.86 (95% CI 0.75-0.96) by Cohen's kappa and 0.93 (95% CI 0.88-0.96) by intraclass correlation coefficient. The inter-rater reliability was 0.67 (95% CI 0.56-0.78) by Cohen's kappa and 0.79 (95% CI 0.69-0.86) by intraclass correlation coefficient. The Spearman correlation coefficients between the VFCS and the GMFCS, MACS, CFCS and EDACS were 0.783, 0.764, 0.738, 0.738 and 0.830, respectively. The concurrent validity was confirmed by the correlations observed with other classification systems.

CONCLUSIONS

The results indicated good reliability and validity for the Japanese version of the VFCS.

Influence of malnutrition and body composition on the gross motor function of children with cerebral palsy in Kano, Nigeria: a cross-sectional study

Background

Malnutrition is common among children with cerebral palsy (CWCP); however, its impact on gross motor function (GMF) is not adequately reported. The study evaluated the influence of malnutrition and body composition on GMF.

Methods

In the cross-sectional survey, CWCP were recruited using purposive sampling from three selected secondary and tertiary hospitals in Kano, Nigeria. Sociodemographic variables were recorded on a data capture form. Anthropometric variables were measured using standard procedures. Percent (%) body fat, malnutrition, and GMF were assessed using skinfold thickness, screening tool for the assessment of malnutrition in pediatrics, and GMF classification system (GMFCS), respectively. The data was analyzed with one-way ANOVA, chi-square, and logistic regression using SPSS version 20 at p < 0.05.

Results

The 146 CWCP have mean age of 4.70 ± 2.46 years. About 95 (65.1%) are malnourished. Those with GMFCS V had lower %body fat and higher malnutrition than children with GMFCS II and I, respectively (p < 0.05). Malnutrition has no significant influence on GMF (B = 0.984, OR = 2.676; 95% CI = 0.965–7.423, p > 0.05). %body fat (B = −0.192, OR = 0.826; 95% CI = 0.687–0.992, p < 0.05), type of CP (OR = 12.106; 95% CI = 3.771–38.866, p < 0.005), child’s position in the family (OR = 1.639; 95% CI = 1.162–2.312, p < 0.05), and mothers’ education (B = −2.815, OR = 0.060; 95% CI = 0.012–0.309, p < 0.005) all predicted GMF.

Conclusions

Majority of the CWCP in this study are malnourished. But malnutrition did not however significantly predict GMF, meaning that though malnutrition could impair children’s physical growth and motor development, it however did not have significant influence on their motor function. Hence, CWCP undergoing rehabilitation may not likely experience significant decrease in their motor function due to inadequate nutrition. Decrease in body fat, type of CP, low level of mothers’ education, and child occupying 4th or more position in the family have negative influence on GMF. It was recommended that physiotherapists should routinely assess for malnutrition in CWCP. Prompt nutritional intervention may prevent considerable lose of body fat and augment the gains of physical rehabilitation by providing appropriate nutrition to support muscle growth and the supply of adequate energy for participation in physical exercise. Adequate caregiver education is important for ensuring satisfactory nutrition for CWCP.

Higher Visual Function Deficits in Children With Cerebral Visual Impairment and Good Visual Acuity

In clinical practice Cerebral Visual Impairment (CVI) is typically diagnosed by observation of abnormal visually guided behaviors which indicate higher visual function deficits (HVFDs) suggesting abnormal brain development or brain damage in a child with a suitable clinical history. HVFDs can occur even in the presence of good visual acuity and may remain undiagnosed because the good visual acuity does not prompt further investigation. This leads to a lack of understanding of the child's visual perceptual difficulties. In a prospective study, we determined the spectrum of HVFDs in a group of children with history suggestive of brain damage or disruption of brain development and an independent diagnosis of CVI in comparison with typically developing children with a structured 51 question inventory, the Higher Visual Function Question Inventory (HVFQI-51) adapted from the Cerebral Vision Impairment Inventory, CVI-I. Here, we show that the HVFQI-51 can detect a range of HVFDs in children with CVI with good visual acuity and clearly distinguishes these children from typically developing children. HVFDs in our study group could mostly be attributed to dorsal stream visual processing dysfunction though the spectrum varied between children. We report on the inclusion of the "not applicable" response option in analysis providing a picture of HVFDs more in tune with the overall disability of each child. We also propose a subset of 11 questions (Top-11) which discriminate between children with CVI vs. behaviors seen in typical children: this provides both a potential screening tool for initial assessment of HVFDs and a measure of CVI-related impairment, and needs further validation in a secondary independent sample.

Evaluating a Therapeutic Powered Mobility Camp for Children with Severe Cerebral Palsy

Background. Children and youth with severe cerebral palsy (CP) have limited independent mobility, which affects opportunities for overall development. Purpose. To examine the effectiveness of Power Fun, a therapeutic powered mobility summer camp. Methods. A quasi-experimental, repeated-measure design was used, with participants acting as their own control. Twenty-four participants with severe CP (aged 7-20 years) attended Power Fun for three weeks, five days/week. Assessments of powered mobility skills and functional mobility goals were conducted three weeks before the camp (T1), at baseline (T2), postintervention (T3), and at three-week follow-up (T4). Findings. An analysis of variance results indicated significant improvements in powered mobility skills (F(1,22) = 56.61, p < 0.001, η²_p = 0.74) and functional mobility goals (F(1,58) = 80.17, p < 0.001, η²_p = 0.74), with 70% of goals achieved postintervention. A descriptive analysis revealed three learning profiles. Implications. This study provides initial evidence supporting the effectiveness of Power Fun as an intervention promoting powered mobility for children with severe CP, across a range of abilities.

Visual Function Classification System for children with cerebral palsy: development and validation

AIM

To develop and validate the Visual Function Classification System (VFCS), which was created to classify how children with cerebral palsy (CP) use visual abilities in daily life.

METHOD

The process of development and validation of the VFCS involved four phases: (1) drafting of the five levels from the analysis of literature and clinical experience; (2) validation of constructs and revision of the levels for concept meaningfulness, using nominal group process; (3) refinement by international Delphi survey; and(4) assessment of interrater reliability among professionals and with caregivers, and of test-retest reliability.

RESULTS

Five nominal groups involved 29 participants; 65 people completed the first round and 51 the second round of the Delphi survey. Construct validity was demonstrated within an expert group and external validation through several stakeholders, with the involvement of patients and families to ensure meaningfulness of the concept. Discussions continued until consensus was reached about the construct and content of the five levels. Participants in the reliability study included 29 professionals, 39 parents, and a total sample of 160 children with CP (mean age [SD] 6y 6mo [3y 4mo]; median 5y 7mo, range 1-19y). Absolute interrater agreement among professionals was 86% (weighted κ=0.88; 95% confidence interval [CI] 0.83-0.93). Test-retest reliability was high (weighted κ=0.97; 95% CI 0.95-0.99). Parent-professional interrater reliability on 39 children was moderate (weighted κ=0.51; 95% CI 0.39-0.63).

INTERPRETATION

The VFCS has been appropriately constructed and provides a reliable system to classify visual abilities of children with CP both in clinical and in research settings.

WHAT THIS PAPER ADDS

The Visual Function Classification System is a valid and reliable system. It classifies visual abilities of children with cerebral palsy in clinical and research settings. At a clinical level, it can be used to harmonize communication among professionals and identify patients' strengths and weaknesses. In research settings, it can be used to stratify patients, define natural history evolution, and interpret intervention studies.

Methods for conceptualising 'visual ability' as a measurable construct in children with cerebral palsy

Background

Vision influences functioning and disability of children with cerebral palsy, so there is a growing need for psychometrically robust tools to advance assessment of children’s vision abilities in clinical practice and research. Vision is a complex construct, and in the absence of clarity about this construct it is challenging to know whether valid, reliable measures exist. This study reports a method for conceptualising ‘visual ability’ as a measurable construct.

Methods

Using the items from 19 assessment tools previously identified in a systematic review, this study used a two-phase process: first, deductive content analysis linked items to the International Classification of Functioning, Disability and Health - Child and Youth version (ICF-CY), and second, vision-specific ‘Activity’-level items were explored using inductive thematic analysis.

Results

The linking and content analysis identified that existing assessment tools are measuring vision across the ICF-CY domains of Body Functions, Activities and Participation, and Environmental and Personal Factors. Items specifically coded to vision at the Activity level were defined as measuring ‘how vision is used’, and these items form the basis of the conceptualisation that ‘visual ability’ is measurable as a single construct.

The thematic analysis led to the identification of 3 categories containing 13 themes that reflect a child’s observable visual behaviours. Seven abilities reflect how a child uses vision: responds or reacts, initiates, maintains or sustains looking, changes or shifts looking, searches, locates or finds, and follows. Four interactions reflect the contexts in which a child uses their vision to purposefully interact: watches and visually interacts with people and faces, objects, over distance, and with hands. Finally, two themes reflect a child’s overall use of vision in daily activities: frequency of use, and efficiency of use.

Conclusions

This study demonstrates an approach to exploring and explaining a complex topic utilising World Health Organization language and building on existing research. Despite the complexity of vision, the concept of ‘how vision is used’ can be clearly defined as a measurable construct at the Activity level of the ICF-CY. This study has identified observable visual behaviours that may be developed into items assessing how vision is used in daily activities.

Electronic supplementary material

The online version of this article (doi:10.1186/s12874-017-0316-6) contains supplementary material, which is available to authorized users.

Measurement of visual ability in children with cerebral palsy: a systematic review

AIM

To identify and evaluate measures of visual ability used with children with cerebral palsy (CP).

METHOD

Eight databases were searched for measures of visual ability. Key selection criteria for measures were: use with children with CP; focus of visual ability measurement at the Activities and Participation domain of the International Classification of Functioning, Disability and Health (ICF). The Consensus-based Standards for the Selection of Measurement Instruments (COSMIN) Checklist was used to assess psychometric properties.

RESULTS

From 6763 papers retrieved, 25 were relevant and 19 measures of visual ability were identified. Only 10 measures were supported with evidence of validity or reliability. No discriminative measure analogous to existing CP functional classification systems was found. No outcome measure valid for evaluation of visual abilities of children with CP was found.

INTERPRETATION

Vision impairment is recognized as relevant to the functioning of children with CP; however, measurement of vision is most often focused at 'Body Function' levels, for example visual acuity. Measuring visual abilities in the Activities and Participation domain is important in considering how a child with CP functions in vision-related activities. The lack of psychometrically strong measures for visual ability is a gap in current clinical practices and research.