The Psychometric Properties of Newsha Developmental Scale: an Integrated Test for Persian Speaking Children

Objective: The term ‘child development’ is used to describe the skills acquired by children between birth and the age of 6 years. Development is rather an integrated process and impairment in one developmental milestone can affect other areas too. The goal of the present study was preparation and determination of validity and reliability of the "Newsha Developmental Scale" as an integrated scale for assessing developmental skills of Persian speaking children up to the age of six years.
Methods: The Newsha developmental scale was created to thoroughly evaluate seven developmental domains in 13 age groups from birth to 72 months. It was based on the concerns of parents and nursery teachers about child development. In order to obtain the scores of normal population, 593 children in nurseries and health centers of Tehran were assessed. The children had no medical concern or confirmed disorders. With consideration of the age of each child, the score of minimum or higher in each developmental milestone was considered as the normal range. The test-retest reliability and inter-rater reliability were measured. In addition, the content validity was assessed by ideas taken from 10 specialists in the field of child development and the content validity Index (CVI) was calculated. Also construct validity was considered by establishing the effect of age on test results.
Findings: A correlation of more than 95% was shown in both test-retest and inter-rater reliabilities (P<0.001). The CVI of various skills of the age groups was between 0.8 and 1, and construct validity revealed the effect of age on the test results. The gender difference was shown only in 6 items among 646 items of the scale (P<0.02).
Conclusion: The "Newsha Developmental Scale" is an integrated and comprehensive scale for evaluating the developmental process of children and identification of any probable delay in developmental abilities of children with Persian language up to 6 years of age.