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51.
Insincere respondents can have an adverse impact on the validity of substantive inferences arising from self-administered questionnaires (SAQs). The current study introduces a new method for identifying potentially invalid respondents from their atypical response patterns. The two-step procedure involves generating a response inconsistency (RI) score for each participant and scale on the SAQ and subjecting the resulting scores to latent profile analysis to identify classes of atypical RI respondent profiles. The procedure can be implemented post–data collection and is illustrated through a survey of school climate that was administered to N = 52,102 high school students. Results of this screening procedure revealed high levels of specificity and expected levels of concordance when contrasted with the results of traditionally used methods of screening items and response time. Contrasts between valid and invalid respondents revealed similar patterns across the three screening procedures when compared across external measures of academics and risk behaviors. 相似文献
52.
S. Gupta R. Shukla K. M. Prabhu S. Aggrawal U. Rusia P. S. Murthy 《Indian journal of clinical biochemistry : IJCB》2002,17(1):58-63
Acute and chronic toxicity studies were conducted to assess toxicity of a partially purified preparation from the water extract
of the bark ofFicus bengalensis, which was demonstrated in our earlier studies to have significant hypoglycemic and hypocholesteroiemic effect on alloxan
induced, mild and severe diabetes in rabbits. LD50 of this preparation was found to be ∼1 gm/kg in rats when given orally. For chronic toxicity studies 3 doses of aqueous preparation
were given to 3 groups of rats. First group received 5 times ED50 (50 mg/kg), second group 10 times ED50 (100 mg/kg) and the third group 15 times ED50 (150 mg/kg) for 3 months. Fourth group which served as control was given water. After three months, blood was collected for
studying biochemical and hematological parameters. Blood glucose, serum cholesterol, liver and kidney function tests, haemoglobin,
total and differential leukocyte count were determined. Animals were sacrificed and histopathological examination of liver,
heart and kidneys was carried out. Results of the study showed that partially purified preparation fromFicus bengalensis is not toxic by all the above mentioned parameters. 相似文献
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54.
Discrepancies among informants’ ratings of a given child's behavior complicate the study of linkages between child behavior and academic achievement. In the current study, we examined the potential moderating effect of informant type on associations between behavior and two types of achievement in a longitudinal growth model that captured children's development from 54 months of age through fifth grade. Latent internalizing and externalizing behavioral constructs, as separately measured by mothers and teachers, were modeled as time‐varying predictors of achievements to capture changes that occur as children progress through different developmental stages. Behavioral ratings obtained by both informants explained largely equivalent levels of reading achievement variance, and teachers’ ratings of child behavior explained more variance in analytic type achievements than did those of mothers. 相似文献
55.
The use of multiple informants is common in assessments that rely on the judgments of others. However, ratings obtained from different informants often vary as a function of their perspectives and roles in relation to the target of measurement, and causes unrelated to the trait being measured. We illustrate the usefulness of a latent variable multilevel multitrait–multimethod measurement model for extracting trait factors from reports of school climate obtained by students (N = 45,641) and teachers (N = 12,808) residing within 302 high schools. We then extend this framework to include assessments of linkages between the resulting trait factors and potential outcomes that might be used for addressing questions of substantive interest or providing evidence of concurrent validity. The approach is illustrated with data obtained from student and teacher reports of two dimensions of school climate, student engagement, and the prevalence of teasing and bullying in their schools. 相似文献