To constantly add to our understanding of child development, a valid, comprehensive, well-researched measure is needed. The recent revision and standardisation of the Griffiths Mental Development Scales - Extended Revised (GMDS-ER) has necessitated investigations into its psychometric properties. This measure is used to identify developmental delays in children and critical decisions may be made, hence it is imperative that this measure be deemed both reliable and valid. This study aimed to contribute to the broader restandardisation project and focussed on gathering qualitative and quantitative construct-related validity evidence for one of the six Subscales of the GMDS-ER, namely the Eye and Hand Coordination Subscale (Subscale D). An exploratory descriptive method using a triangulation approach was used to explore the construct-related validity evidence of the Eye and Hand Coordination Subscale. A non-random purposively selected sample of 6 experts, who had worked at least 10 years with children assessing and evaluating the domain of eye-hand coordination, participated in a facet analysis to identify the underlying dimensions tapped by the Eye and Hand Coordination Subscale. The sample for the quantitative aspects of this study, the empirical validation of the construct model, was collected as part of the broader restandardisation and represented a stratified sample of 1026 children between the ages 24 months and 96 months from across the United Kingdom and Eire. Three measures, namely a biographical questionnaire, the GMDS-ER and a construct evaluation form were used to gather the qualitative and quantitative data. The qualitative data was analysed by means of a facet analysis and literature control which included examining other tests or subtests that tapped eye-hand coordination skills. The quantitative data was analysed by means of exploratory common factor analysis using oblique (DQUART) rotation in order to verify the qualitatively identified construct model by specifying a one-factor solution for each underlying construct. While literature suggests that eye-hand coordination is multidimensional in nature the facet analysis revealed that the tasks tapped by Subscale D were not tapping complex skills aside from eye-hand coordination. The facet analysis thus revealed that all the items tap the eye-hand coordination of fine motor tasks and that these items could be grouped into two categories, using writing utensils and object manipulation. The results from the factor analysis confirmed that the items on Subscale D have one underlying construct and further exploration confirmed that these items could in fact be grouped into two categories. The coefficients of congruence for SES and gender were satisfactory and thus the construct model was validated across these groups as well. The study has provided extensive qualitative and quantitative evidence for the construct-related validity of the Eye and Hand Coordination Subscale of the GMDS-ER, thus validating its use as a sound measure of eye-hand coordination development in children aged 2 to 8 years. The content coverage however, seemed to indicate that the tasks required do not adequately cover all the facets of eye-hand coordination and some of these item types are tapped by the other Subscales in the measure. Hence, should the Subscale be used as an independent assessment of eye-hand coordination, the eye-hand coordination development of the child would have a narrow focus. In addition, in reviewing the variety of tasks in the two sections for the older and younger child, the researcher noted that while section III tapped a variety of skills, section IV only focused on skills associated with drawing, copying and writing. A review of the age appropriateness of the items and the item analysis results from the revision seemed to indicate that some of the items assessing the older child may need to be revised. Further, the researcher suggested that the revision should consider adding additional dimensions to the tasks assessed. Overall, it is the researcher‟s opinion that this Subscale was not given adequate attention during the revision process and should future revisions occur, the recommendations from this study should be considered.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:nmmu/vital:9923 |
| Date | January 2008 |
| Creators | Povey, Jenny-Louise |
| Publisher | Nelson Mandela Metropolitan University, Faculty of Health Sciences |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis, Doctoral, DPhil |
| Format | xiii, 400 leaves ; 30 cm, pdf |
| Rights | Nelson Mandela Metropolitan University |
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