Developing of the Persian Version of Bayley Scales of Infant and Toddlers Development Screening Test and Determine its Validity and Reliability

The aim of the study was to develop a valid and reliable Persian version of the Bayley Scales of Infant and Toddlers Development Screening Test. Forward and backward translation, face and content validity determination, and cultural and linguistic adaptations of the questionnaires were performed, consecutively. Clarity of items of the translated version of the scale were examined by a study that carried out on 45 Persian 1- to 42-month-old children, recruited by sampling in Tehran, during the year 2012. In order to determine the reliability; internal consistency, inter-rater and test-retest, 34 tests carried out. For determining the psychometric properties of the tests, later a representative sample of 260, 1- to 42-months-old children recruited through consecutive sampling from health -care centers in five main districts in Tehran. Performing cultural and lingual adaptations, our expert team made some inevitable changes to the test items. Almost in all age groups, cultural or linguistic changes were made in items in communication domains. The Cronbach alpha in cognitive, communication (receptive and expressive), fine and gross motor subtests were 0.96, 0.95. 0.95 and 0.94 respectively. The construct validity of the tests by factor analysis and comparison of mean scores in age groups was confirmed. The Persian version of the Bayley Scales of Infant and Toddlers Development Screening test is a valid and reliable tool.