Intelligence of visually impaired children

Įvairiose šalyse trūksta standartizuotų testų akliesiems, todėl jų intelektiniai gebėjimai vertinami panaudojant verbalinius regintiesiems skirtų testų subtestus arba modifikuojant neverbalinius. Lietuvoje aklųjų ir silpnaregių intelektiniai gebėjimai vertinami WISC-III Verbaline skale. Olandų sukurtas ITVIC testas (vadovas yra išleistas anglų kalba) yra skirtas įvairiems, tiek verbaliniams, tiek neverbaliniams, aklų vaikų intelektiniams gebėjimams įvertinti. Gavus autorių sutikimą adaptuoti testą Lietuvoje, buvo išverstas testo vadovas. Remiantis 7–16 m. vaikų, kurie mokosi Brailio raštu (N = 41), ITVIC atlikimo rezultatais, vertinami testo patikimumo ir validumo rodikliai. Atliekant ITVIC rezultatų analizę, dalijimo pusiau ir vidinio suderinamumo metodu buvo patvirtintas visų subtestų, išskyrus Namo plano, patikimumas ir turinio validumas. Verbalinių ITVIC subtestų koreliacijos su verbaliniais WISC-III subtestais bei ITVIC subtestų įverčių koreliacijos su mokymosi rezultatais leidžia daryti išvadą apie pakankamą testo kriterijaus validumą. Palyginus lietuvių vaikų subtestų atlikimo rezultatus su olandų bei lietuviškomis WISC-III normomis, galima daryti išvadą, jog 13,5 m. vaikų, neturinčių naudingos regos, rezultatų analizei galima panaudoti olandiškų 7 subtestų ir lietuviškas Žodyno normas.Problems and possibilities assessing intellectual abilities of visually impaired children are addressed in the article. In other countries, usually there are few or no nationally standardized tests available for use with this population. Therefore parts of available instruments designed for normally sighted children are used. Sometimes test procedures or stimuli are modified what affects the validity of the results and they need to be interpreted with caution. Intellectual abilities of Lithuanian visually impaired children are currently assessed using WISC-III Verbal scale. We discuss the possibility to use ITVIC (Intelligence test for visually impaired children) test for the assessment of intellectual abilities of Lithuanian children. ITVIC was designed in The Netherlands for an assessment of intellectual abilities of Braille educated visually impaired children aged 6– 15 years. The authors used Thurstone Primary factor theory as theoretical starting point. ITVIC has both, verbal and haptic subtests and two types of norms: age norms for all Braille educated children and age norms for two vision groups within the population of Braille educated children separately. ITVIC Manual is transla- ted to English which made it accessible for using in Lithuania. After we received the permission from publishers and test author, translation of ITVIC manual was made. Based on results from 41 Lithuanian Braille educated children aged 7–16 years, evaluation of ITVIC reliability and validity was made. Data analysis based on method of internal consistency and Split half reliability analysis confirmed good reliability of all ITVIC subtests except House plan questions. This subtest also has low content validity. Correlations between ITVIC subtests and school achievement results show adequate criterion validity of the test. The means of subtest scores in Lithuanian and Dutch population were compared for the group of children without usable vision aged >13,5 years. The scores of two WISC-III subtests as part of ITVIC test were compared to Lithuanian WISC-III norms. The results show that results of 7 ITVIC subtests can be interpreted using Duch norm tables and Lithuanian WISC-III Vocabulary norms for this age group