Secondary Education Teachers
The aim of this research was to adapt the LPI to Turkish language and determine its psychometric properties.
A random sample of 436 primary and secondary school teachers in Konya/Turkey were selected for the study; 194 were female (44%) and 242 were male (56%). Their average years of teaching experience were 15. The Leadership Practices Inventory was first translated into Turkish by English teaching experts, then the Turkish text was retranslated into English, compared with the original text and found to be identical with it. A five-point scale was used rather than a 10-point scale for responses (“because the scale is considered to be more clearly understood”).
Twenty-five English Language teachers completed both the Turkish and English language versions of the LPI over a 2-4 week time interval and correlation coefficients between the Turkish and English forms of the scale overall was .91. Exploratory factor analysis with varimax rotation was performed and some of the scale items were in different sub dimensions from the original scale. In the Turkish version, Model the Way had three items, Inspire a Shared Vision had nine items, Challenge the Process had five items, Enable Others to Act had six items and Encourage the Heart had seven items. “Confirmatory factor analysis (first and second order) revealed adaptive values for the model as Chi-square (p < .000), Goodness of Fit Index (GFI=0.84), Normed Fit Index (NFI=0.90) Root Mean Square Factor of Approximation (RSME=0.069). 0.86 and high GFI< AGFI, NFI values obtained from the first and second-order CFA were the results of the good coherence of the data to the model. Furthermore, RMSEA value between 0.05 and 0.10 showed that the model was in acceptable adaptive value” (p. 149).
Internal reliability (Cronbach alpha) for the whole scale as .98, with Model at .82, Inspire at .95, Challenge at .87, Enable at .91 and Encourage at .92. Split-half reliability using Spearman Brown formula was .96 for the whole scale and ranged between .85 and .96 for the five practices. Split-half reliability using the Guttman Split-Half technique for the whole scale was .95 and for the five leadership practices ranged between .78 and .93.
Item total correlation, according to the author, “explains the relation between the points taken from the test items and the total points of the test. High and positive total-item correlation shows that items exemplify similar behaviors. Statistical relevance can be taken as a criterion in interpreting the total-item correlation. Furthermore, it is usually accepted that items which have .30 and higher item total correlation distinguish between the individuals well. Another way in the extend of item analysis is to test the differences between the item average points of the 27 percentage lower group and the 27 parentage higher group constituted according to total points of the test by using non-related t test. Observed meaning differences can be evaluated as an indicator of internal coherence of the test. According to the result of the data analysis, it was observed that item total correlations of Leadership Practices Scale were between .66 and .84 t values (df=155) related to the differences in item points of 27 percentage lower and higher groups determined according to total points were between -12.10 and -24.69 (p < .001). In these premises, it was concluded that items distinguished the individuals well and the test had interval coherence” (p. 151).