Design and validation of a multidimensional vocal scale for teachers to detect vocal risks

The objective of the study was to design, according to criteria of specificity and simplicity, a vocal multidimensional and reliable
scale (EVM-D), that contributes to detect situations of vocal risk of the teachers in the school context. 

The study involved 299 teachers from 18 randomly selected schools from A Coruña that were divided into two sub-samples, one of them (n =143) 
for exploratory factor analysis, both with Parallel Analysis and principal axis factorization and oblimin rotation and another sub-sample (n = 156) for
confirmatory factor analysis, using the weighted least squares method.
The EVM-D was developed in two stages: 1) The design of the scale with the selection of the most 
appropriate items for the vocal self-analysis and 2) the evaluation of the validity of the construct and the reliability of the instrument.