Dear Elham,
Have you considered doing focus group discussion sessions and/or individual in-depth interviews in order to come up with some items appropriate to the culture/society in which the teachers live? To considerable extent, disciplinary style is both culturally and historically determined. It would seem that you will make a greater contribution by using both qualitative and quantitative approaches in your study. But, if you are going to limit yourself to one approach, use qualitative; especially if no one has utilized this approach to study your target group. In other words, you do the qualitative as a first set, content analyze the transcription of the interviews and/or observations and then generate items that can be included in the qualitative instrument.
It is important that you conduct a search to determine what, if anything has already been done, in general and, in particular, among the target population.