Purpose: The aim of this study was to standardize and evaluate the psychometric properties of mid-childhood developmental assessment (MDI).
Materials and Methods: The research design is a test-making research. This research is also applied in terms of purpose. The statistical population of the present study was all primary school students in Tehran (ages 6 to 12 years) in 1398. In this study, 469 people were selected as the available sample group. The research tool was measuring development in mid-childhood. Classical validation (Cronbach's alpha and retest), heuristic factor analysis and convergent evidence were used for data analysis.
Findings: The results of factor analysis showed that 5 scale factors explained 53.89% of the variance. Reliability analysis of the test showed that Cronbach's alpha coefficients of the subscales are higher than 0.7. The flexibility factor also had the highest coefficient of validity. Also, in all subscales, Pearson correlation coefficient between two runs was higher than 0.85. The correlation between the subscales of measurement of development in mid-childhood confirmed the convergent evidence of the questionnaire.
Conclusion: Based on the results of the research, the research evidence supports the simultaneous study and consideration of all five subscales of the Persian version of mid-childhood developmental assessment