Exploring the construct-related validity of the personal-social subscale of the Griffiths Mental Development Scales-extended revised (GMDS-ER)
- Authors: Moosajee, Shaheda
- Date: 2007
- Subjects: Psychological tests for children , Griffiths Scales of Mental Development
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9934 , http://hdl.handle.net/10948/572 , http://hdl.handle.net/10948/d1011708 , Psychological tests for children , Griffiths Scales of Mental Development
- Description: Child assessment has become imperative today as parents and teachers recognize the need for early diagnostic assessments to adequately cater for children’s’ diverse and growing needs so that children can benefit from services and attention in a psychological or educational setting. The Griffiths Mental Development Scales, an established and well-researched instrument is reported to be one of the most carefully designed measures of child development . Studies in various parts of the world have demonstrated that the Griffiths Scales are applicable to diverse populations and that they tap experiences that are common to different cultures. The recent revision and restandardisation of the Griffiths Mental Developmental Scales-Extended Revised (GMDS-ER) has necessitated investigations into its psychometric properties. In view of the important role that assessment measures play in the early identification of developmental delays, it is important that assessment measures are reliable and valid for their intended purpose(s). This study, which is part of a larger research project, attempted to explore and add further evidence of the construct validity of one of the six Subscales of the GMDS-ER, namely the Personal-Social Subscale (Subscale B). An exploratory-descriptive design using a triangulation approach was utilized to explore the construct validity of the Personal-Social Subscale. A nonprobability purposively selected sample of 18 experts working with children participated in the facet analysis to identify the constructs underlying Subscale B (the qualitative aspect of the study). The sample for the quantitative aspects of this study (i.e., the empirical validation of the identified constructs) was collected as part of the broader restandardisation and represented a stratified random sample of 1026 children between the ages of 3 and 8 years 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 facet analysis and literature control. The quantitative data was analysed by using exploratory common factor analysis using oblique (DQUART) rotation to empirically verify the qualitatively identified construct model by specifying a onefactor solution for each underlying construct.
- Full Text:
- Date Issued: 2007
- Authors: Moosajee, Shaheda
- Date: 2007
- Subjects: Psychological tests for children , Griffiths Scales of Mental Development
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9934 , http://hdl.handle.net/10948/572 , http://hdl.handle.net/10948/d1011708 , Psychological tests for children , Griffiths Scales of Mental Development
- Description: Child assessment has become imperative today as parents and teachers recognize the need for early diagnostic assessments to adequately cater for children’s’ diverse and growing needs so that children can benefit from services and attention in a psychological or educational setting. The Griffiths Mental Development Scales, an established and well-researched instrument is reported to be one of the most carefully designed measures of child development . Studies in various parts of the world have demonstrated that the Griffiths Scales are applicable to diverse populations and that they tap experiences that are common to different cultures. The recent revision and restandardisation of the Griffiths Mental Developmental Scales-Extended Revised (GMDS-ER) has necessitated investigations into its psychometric properties. In view of the important role that assessment measures play in the early identification of developmental delays, it is important that assessment measures are reliable and valid for their intended purpose(s). This study, which is part of a larger research project, attempted to explore and add further evidence of the construct validity of one of the six Subscales of the GMDS-ER, namely the Personal-Social Subscale (Subscale B). An exploratory-descriptive design using a triangulation approach was utilized to explore the construct validity of the Personal-Social Subscale. A nonprobability purposively selected sample of 18 experts working with children participated in the facet analysis to identify the constructs underlying Subscale B (the qualitative aspect of the study). The sample for the quantitative aspects of this study (i.e., the empirical validation of the identified constructs) was collected as part of the broader restandardisation and represented a stratified random sample of 1026 children between the ages of 3 and 8 years 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 facet analysis and literature control. The quantitative data was analysed by using exploratory common factor analysis using oblique (DQUART) rotation to empirically verify the qualitatively identified construct model by specifying a onefactor solution for each underlying construct.
- Full Text:
- Date Issued: 2007
Collaborative research with traditional African health practitioners of the Nelson Mandela Metropole : antimicrobial, anticancer and anti-diabetic activities of five medicinal plants
- Authors: Van Huyssteen, Mea
- Date: 2007
- Subjects: Medicinal plants -- South Africa -- Port Elizabeth , Healers -- South Africa -- Port Elizabeth , Anti-infective agents
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10148 , http://hdl.handle.net/10948/663 , Medicinal plants -- South Africa -- Port Elizabeth , Healers -- South Africa -- Port Elizabeth , Anti-infective agents
- Description: The promotion and development of indigenous knowledge pertaining to the traditional African healing system is one of the prime objectives set out by the South African government. Despite excellent research opportunities and funding, the biggest problem with ethnopharmacological research is a lack of interaction with indigenous communities, which tends to dilute the benefits this research has to offer these communities. The primary aim of this study was thus to promote the traditional African healing system through collaborative medicinal plant research with local traditional health practitioners. The research collaboration aimed to validate some biological activities of traditional remedies used by collaborating traditional health practitioners and ensured interactive sessions where scientific literature, research practices, findings and relevant legislation were discussed and debated. The joint development of a medicinal garden was a valuable tool in realising these goals. Aqueous and ethanol extracts of Bulbine frutescens, Ornithogalum longibracteatum, Ruta graveolens, Tarchonanthus camphoratus and Tulbaghia violacea were selected for antimicrobial, anticancer and anti-diabetic screening, because of their sustainable utilisation potential. The ethanol extract of T. violacea produced the best antimicrobial activity on Bacillus subtilis (100% growth inhibition) and Candida albicans (89% growth inhibition) at 250 μg/ml. The EC50 for the ethanol extract of T. violacea against HT29 colon cancer cells was 101 μg/ml. The aqueous extracts of B. frutescens and T. camphoratus (0.5 and 50 μg/ml) produced the highest overall glucose uptake activity in Chang liver and C2C12 muscle cells. T. camphoratus was unanimously chosen by participating practitioners as the plant to be investigated further. The aqueous extract of T. camphoratus increased glucose uptake in C2C12 muscle cells through increased translocation of GLUT4 to the plasma membrane and activation of the PI3-kinase and AMP-kinase pathways. It produced some alpha-glucosidase inhibitory activity at concentrations of ≥ 200 μg/ml. Apart from interactive feedback seminars at which the findings were presented to participating practitioners, all scientific literature regarding the plants was summarised, translated, compiled and given to participating practitioners in written format. An indigenous knowledge agreement has been negotiated and will formalise the collaboration in future. It is recommended that future research focuses on plants with economic development potential that can be cultivated in the medicinal garden.
- Full Text:
- Date Issued: 2007
- Authors: Van Huyssteen, Mea
- Date: 2007
- Subjects: Medicinal plants -- South Africa -- Port Elizabeth , Healers -- South Africa -- Port Elizabeth , Anti-infective agents
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10148 , http://hdl.handle.net/10948/663 , Medicinal plants -- South Africa -- Port Elizabeth , Healers -- South Africa -- Port Elizabeth , Anti-infective agents
- Description: The promotion and development of indigenous knowledge pertaining to the traditional African healing system is one of the prime objectives set out by the South African government. Despite excellent research opportunities and funding, the biggest problem with ethnopharmacological research is a lack of interaction with indigenous communities, which tends to dilute the benefits this research has to offer these communities. The primary aim of this study was thus to promote the traditional African healing system through collaborative medicinal plant research with local traditional health practitioners. The research collaboration aimed to validate some biological activities of traditional remedies used by collaborating traditional health practitioners and ensured interactive sessions where scientific literature, research practices, findings and relevant legislation were discussed and debated. The joint development of a medicinal garden was a valuable tool in realising these goals. Aqueous and ethanol extracts of Bulbine frutescens, Ornithogalum longibracteatum, Ruta graveolens, Tarchonanthus camphoratus and Tulbaghia violacea were selected for antimicrobial, anticancer and anti-diabetic screening, because of their sustainable utilisation potential. The ethanol extract of T. violacea produced the best antimicrobial activity on Bacillus subtilis (100% growth inhibition) and Candida albicans (89% growth inhibition) at 250 μg/ml. The EC50 for the ethanol extract of T. violacea against HT29 colon cancer cells was 101 μg/ml. The aqueous extracts of B. frutescens and T. camphoratus (0.5 and 50 μg/ml) produced the highest overall glucose uptake activity in Chang liver and C2C12 muscle cells. T. camphoratus was unanimously chosen by participating practitioners as the plant to be investigated further. The aqueous extract of T. camphoratus increased glucose uptake in C2C12 muscle cells through increased translocation of GLUT4 to the plasma membrane and activation of the PI3-kinase and AMP-kinase pathways. It produced some alpha-glucosidase inhibitory activity at concentrations of ≥ 200 μg/ml. Apart from interactive feedback seminars at which the findings were presented to participating practitioners, all scientific literature regarding the plants was summarised, translated, compiled and given to participating practitioners in written format. An indigenous knowledge agreement has been negotiated and will formalise the collaboration in future. It is recommended that future research focuses on plants with economic development potential that can be cultivated in the medicinal garden.
- Full Text:
- Date Issued: 2007
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