The aim of this study was to evaluate the psychometric properties of the Problematic Mobile Phone Use Scale (PMPUS) for Turkish Adolescents. The psychometric properties of PMPUS were tested in two separate sample groups that consisted of 950 Turkish high school students. The first sample group (n=309) was used to determine the factor structure of the scale. The second sample group (n=461) was used to test data conformity with the identified structure, discriminant validity and concurrent scale validity, internal consistency reliability calculations, and item statistics calculations. The results of exploratory factor analyses indicated that the scale had three factors: interference with negative effect, compulsion/persistence, and withdrawal/tolerance. The results showed that item and construct reliability values yielded satisfactory rates in general for the three-factor construct. On the other hand, the average variance extracted value remained below the scale value for three subscales. The scores for the scale significantly correlated with depression and loneliness. In addition, the discriminant validity value was above the scale in all sub-dimensions except one. Based on these data, the reliability of the PMPUS scale appears to be satisfactory and provides good internal consistency. Therefore, with limited exception, the PMPUS was found to be reliable and valid in the context of Turkish adolescents.

This study aimed to develop mathematics teaching anxiety scale for prospective primary school teachers. It was designed based on survey method and conducted with four sampling group consisting of 956 prospective primary school teachers at Education Faculties in Turkey. First sampling group was consisted of 404 prospective primary school teachers and 96 out of it were involved in the application of open-ended questions and 308 were involved in exploratory factor analysis. 305 prospective primary school teachers in the second sampling group participated in the confirmatory factor analysis, 108 prospective teachers in the third group were involved in criterion validity and 139 prospective teachers in the fourth one participated in the test-retest reliability analysis. As a result of the principal component analysis of the Mathematics Teaching Anxiety Scale (MTAS), it was found that the scale indicating single factor structure and consisting of 31 items (47.43% of the total variance). After suggested modifications, the scale MTAS was constructed with 19 items. 12 items were removed from the scale and the confirmatory factor analysis (CFA) was carried out with 19 items. According to CFA results (0≤X2 / df = 1.483≤2, RMSEA = 0.040, RMR = 0.050, AGFI = 0.908, TLI = 0.972, CFI = 0.976, IFI = 0.976, GFI = 0.928, NFI = 0.930 and RFI = 0.919), it was confirmed that the scale structure was consisting of 19 items and one dimension. The Cronbach's alpha coefficient of the final form of Mathematics Teaching Anxiety Scale was calculated as 0.93.

Highlights• Mathematics lecture achievement is the most important predictor of academic achievement.• Turkish lecture achievement is the second significant predictor of academic achievement.• The mathematics and Turkish lecture achievement are followed by academic self-efficacy.