Constructing and Evaluating Reliability and Validity of a Diagnostic Spelling Test for Third Grade Elementary School Students

The purpose of this study was to construct a diagnostic spelling test for thirdgrade elementary school students and to evaluate its reliability and validity. The population included all third grade students of elementary school in Kermanshah and Kangavar region in the 2012-2013 school year. The sample consisted of 30 normal students and 30 student with spelling disorder (who had been referred to the region’s center for rehabilitation of learning disorders), who were chosen through random sampling. The test was constructed based on the third grades main spelling textbook and it included 115 words. The test’s reliability was determined using Cronbach's alpha, which yielded the satisfactory result of 0.98. The validity was evaluated using group differentiation, cut point determination and interpreting the ROC curve between the two groups. The average test score for normal students was 18.18 (out of 20) and for students with LD it was 4.96, which showed a significant difference (p < 0.05) and thus established the validity of the test. The cut point score from the ROC curve was 13.40. The study successfully established reliability and validity of the constructed test, and suggests it as a tool for diagnosing spelling problems in third grade elementary students.