IADR Abstract Archives
Psychometric properties of Child Oral-care Performance Assessment Scale.
Objectives: This study aimed to assess the psychometric properties of Child Oral-care Performance Assessment Scale (COPAS), which is the first multi-item measurement instrument built to assess performance of oral care systems targeted at children.
Methods: Data from a national survey (National Child Oral Health Survey 2012-14), whose aims included the assessment of oral-care performance, were used in this study. This nationally representative sample of 23,538 respondents with complete data was divided into five groups: a main validation group and four cross-validation groups. This split was accomplished using a random selection strategy using blocked randomization, where the block size was five. Two scales were constructed, full scale with 38 items (COPAS) and a partial scale with a sub-set of 33 items (COPAS-Partial). Internal consistency was assessed using Cronbach’s alpha. Construct validity was assessed using correlation coefficients and structural validity was ascertained in the main validation group and confirmed in the cross-validation groups using structural equation models with maximum likelihood estimate that accounted for missing values.
Results: Cronbach’s alpha for COPAS was 0.954, and for COPAS-Partial was 0.943. The data split resulted in equivalent groups. The convergent validity of global satisfaction with oral care and the sub-scales reported rho=0.21 to 0.47, and that with the overall scales reporting rho=0.53 for COPAS and rho=0.56 for COPAS-partial. The fit indices reported for the main validation sample were Root mean squared error of approximation of 0.063, Comparative fit index of 0.899, Tucker-Lewis index of 0.891 and Coefficient of determination of 0.990. Structural invariance between the five cross-validation groups was assessed and found with a p-value of 0.969.
Conclusions: There was acceptable structural validity, construct validity and internal consistency in the models tested for COPAS and COPAS-Partial. COPAS has potential use in the evaluation of the delivery of dental services to children.
Methods: Data from a national survey (National Child Oral Health Survey 2012-14), whose aims included the assessment of oral-care performance, were used in this study. This nationally representative sample of 23,538 respondents with complete data was divided into five groups: a main validation group and four cross-validation groups. This split was accomplished using a random selection strategy using blocked randomization, where the block size was five. Two scales were constructed, full scale with 38 items (COPAS) and a partial scale with a sub-set of 33 items (COPAS-Partial). Internal consistency was assessed using Cronbach’s alpha. Construct validity was assessed using correlation coefficients and structural validity was ascertained in the main validation group and confirmed in the cross-validation groups using structural equation models with maximum likelihood estimate that accounted for missing values.
Results: Cronbach’s alpha for COPAS was 0.954, and for COPAS-Partial was 0.943. The data split resulted in equivalent groups. The convergent validity of global satisfaction with oral care and the sub-scales reported rho=0.21 to 0.47, and that with the overall scales reporting rho=0.53 for COPAS and rho=0.56 for COPAS-partial. The fit indices reported for the main validation sample were Root mean squared error of approximation of 0.063, Comparative fit index of 0.899, Tucker-Lewis index of 0.891 and Coefficient of determination of 0.990. Structural invariance between the five cross-validation groups was assessed and found with a p-value of 0.969.
Conclusions: There was acceptable structural validity, construct validity and internal consistency in the models tested for COPAS and COPAS-Partial. COPAS has potential use in the evaluation of the delivery of dental services to children.