Psychometric derivation of the short form teacher disposition scale (TDS-11)

While there is growing awareness of the critical role teacher dispositions play in effective pedagogy there are few validated instruments available to provide reliable measurements for researchers and teacher educators. A notable exception is the Teacher Disposition Scale, a recently created multidimensional instrument which has shown potential as a measure of teaching dispositions. However, as a new scale, little psychometric information is available and, moreover, the limited prior research conducted has found poor psychometric functioning in a number of the subscales. Hence, the purpose of the current study was to provide further psychometric information on the scale using a large sample of undergraduate pre-service teachers (N = 1,318). Using a combination of factor analyses and Rasch modelling, a psychometrically sound, short form scale was derived consisting of 11 items. The paper concludes with a discussion of the utility of a reliable short form instrument to the field of teaching disposition research.