Middle Eastern Journal of Disability Studies

Abstract

Background and Objective: In the context of learning disabilities evaluation, one of the few diagnostic-prescriptive tools is the fourth edition of the Learning Disability Evaluation Scale (McCarney and House, 2018), which, in addition to its diagnostic application, also provides suggestions for relevant interventions, leads to an individualized educational plan. The provided interventions are based on the seven-component theoretical structure of this scale with a logical combination. The present study was conducted to validate the seven-component structure of the Diagnostic and Prescriptive Learning Disability Evaluation Scale (McCarney & House, 2018) among second to fifth-grade students.
method: This was descriptive-analytical research of tool developing type. The statistical population of the research consisted of second to fifth-grade students in 1400-1401. According to the announcement of the cooperation of elementary school principals, Tehran, Mazandaran, and Lorestan provinces were selected using the available sampling method. Then, in each of these provinces, cities, elementary schools, and learning disability centers were also selected using the available sampling method. Finally, following the minimum required sample size according to Mayers (2013) and taking into account the entry and exit criteria, the standard sample group consisting of 298 students (145 girls and 153 boys) was selected by simple random and purposeful sampling method by the teachers of selected schools and the clinical sample group consisting of 27 people (9 girls and 18 boys) of students with learning disabilities were selected by the available sampling method by the educators of the selected learning disability centers. This study was conducted to validate the fourth edition of the Diagnostic-Prescriptive Learning Disability Evaluation scale (LDES-4) (McCarney and House, 2018). To adapt this scale to Persian culture and language based on the method presented by the World Health Organization in 2006, the following steps were performed: direct translation, referral to an expert panel and reverse translation, obtaining cognitive information through clinical interviews, and finally compiling the final version and documenting. The Colorado Learning Difficulties Questionnaire (Willcutt et al., 2011) was used to explore concurrent validity. To determine the content validity, the Content Validity Ratio (CVR) and Content Validity Index (CVI) were calculated using the opinions of 6 professors and experts in the field of learning disabilities. To probe the construct validity, Confirmatory Factor Analysis was utilized using the Maximum Likelihood Estimation method in AMOS26. Also, internal consistency was investigated by Cronbach's alpha method, and temporal stability by test-retest reliability method with a time interval of four weeks in the clinical sample group using the intraclass correlation coefficient. For concurrent validity the Pearson correlation coefficient was calculated in the clinical sample group. In addition, in order to check the discriminant validity, 27 students of the normal sample group, who were equal to the clinical sample group (27 people) in terms of gender, educational level and place of residence, were selected randomly and their scores were compared with the scores of  the clinical sample gtoup through independent t-test. In this study, to perform the confirmatory factor analysis, AMOS26 software was used and the rest of the statistical analyzes were performed using SPSS26, at the significance level of 0.05.
Results: Based on the results of calculating the Content Validity Ratio, two items with CVR = 0.66 were removed from the scale. In the Confirmatory Factor Analysis using Item Parcel modifying method, the fit indices include CMIN/df = 3.88, CFI = 0.96, PCFI = 0.97, and IFI = 0.96, indicating the desired fitness of the seven-component structure of the diagnostic-prescriptive learning disability evaluation scale with the data. In examining the discriminant validity, there was a significant difference between the scale’s total score in two normal and clinical groups (p < 0.001). The value of Cronbach's alpha for the whole scale and each of the components was calculated more than 0.70. Also, the Intraclass Correlation Coefficients with a confidence interval of 95%, for the whole scale and its seven components, ranged from 0.891 to 0.970 (the lowest value related to the thinking component and the highest related to the speaking component), which was significant (p< 0.001) indicated the appropriate temporal stability of the scale. Also, a positive and significant relationship was obtained between the total score of this scale and the total score of the Colorado Learning Difficulties Questionnaire (Willcutt et al., 2011) (p < 0.01).
Conclusion: The fourth edition of the Diagnostic-Prescriptive Learning Disability Evaluation scale (LDES-4) with a seven-component structure can be used as a valid and reliable tool to assess learning disabilities in second to fifth-grade students.