Strabismus and visual abilities

Abstract

The aim of the research was to determine the relations between visual abilities and strabismus of children of junior school age. By the census method for sample formation we selected 1165 children from urban, suburban and rural parts of the territory of Belgrade, boys and girls aged 7.5 to 11. For screening evaluation we used the Cover test. The Acadia test of developmental capabilities was used for estimating visual abilities. Strabismus was diagnosed in 80 cases (6.9%). There were no statistically significant differences in the distribution of strabismus across different ages (x2=3,611, df=2, p=0,164) or gender (x2=0,694, df=1, p=0,405) of the respondents. After determining the prevalence of strabismus we formed an experimental and a control group. The experimental group included 80 children with strabismus, and 150 children formed the control group. Statistically significant is the influence of strabismus on the results of the Acadia test grouped in a model of visual abilities (Wilks' λ=0,987, F(6,230)=2,534, p=0,019). Statistically significant differences between the respondents with strabismus and those without strabismus in the areas of visual-motor coordination and nonverbal concluding were found after analyzing the relation between strabismus and subtests of the Acadia tests. In the area of visual association there was a statistically significant difference between two groups of respondents (F(1)=6,947, p=0,009). In other examined areas no statistically significant differences between children with and without strabismus were found. Children with strabismus acquire lower achievements in the areas of visual-motor coordination and nonverbal concluding than the children without strabismus. The respondents with strabismus of all ages lag behind compared to their counterparts without strabismus, but the difference of the arithmetic means diminishes in the fourth grade.

Cilj rada je utvrđivanje odnosa između vizuelnih sposobnosti i strabizma kod dece mlađeg školskog uzrasta. Cenzus metodom formiranja uzorka odabrano je 1.165 dece iz urbanih, suburbanih i ruralnih delova teritorije Beograda, oba pola, uzrasta 7,5 -11 godina. Za skrining procenu strabizma korišćen je Test pokrivanja (Cover test). Za procenu vizuelnih sposobnosti korišćen je Akadija test razvojnih sposobnosti. Utvrđeno je prisustvo strabizma kod 80 (6,9%) ispitanika. Nisu utvrđene statistički značajne razlike u zastupljenosti strabizma kod ispitanika različitog uzrasta (h2=3,611, df=2, p=0,164) i pola (h2=0,694, df=1, p=0,405). Nakon utvrđivanja prevalencije strabizma, formirane su eksperimentalna i kontrolna grupa. Eksperimentalnu grupu je činilo 80 dece sa strabizmom, a kontrolnu 150 dece bez strabizma. Strabizam statistički značajno utiče na rezultate Akadija testa grupisane u model vizuelnih sposobnosti (Wilks' λ=0,987, F(6230)=2,534, p=0,019). Analizom odnosa između strabizma i suptestova Akadija testa utvrđeno je postojanje statistički značajnih razlika između ispitanika sa strabizmom i bez strabizma u oblastima vizuomotoričke koordinacije i neverbalnog zaključivanja. U oblasti vizuelne asocijacije je utvrđena statistički značajna razlika u dinamici razvoja između dve grupe ispitanika (F(1)=6,947, p=0,009). U ostalim procenjenim domenima nisu utvrđene statistički značajne razlike između dece sa strabizmom i dece bez strabizma. Deca sa strabizmom ostvaruju niža postignuća u oblastima vizuomotoričke koordinacije i neverbalnog zaključivanja u odnosu na decu bez strabizma. Na svim uzrastima ispitanici sa strabizmom zaostaju za postignućima dece bez strabizma, ali se razlika aritmetičkih sredina smanjuje u IV razredu.