Two versions of the test were created, which were contrasted by a bilingual investigator to obtain a preliminary version in Spanish. This preliminary version was subjected to a blind and independent back-translation by other two translators, who did not know the original test, thus obtaining two versions of the instrument in its original language.
Esta versión preliminar fue sometida a una retro-traducción ciega e independiente por otros dos traductores, quienes no conocían el test original, obteniendo nuevamente dos versiones del instrumento en su lenguaje original.