Select one valid and reliable instrument used to measure one or more observable

Select one valid and reliable instrument used to measure one or more observable

Select one valid and reliable instrument used to measure one or more observable variables of leadership and: (a) describe the theoretical foundations of the proposed research instrument; (b) describe how the original creators developed the instrument (c) describe the procedures for establishing validity and reliability of the proposed instrument, and (d) discuss threats to internal validity of the proposed instrument.
Please watch the video: Minor Project 2

MIST WATCH VIDEO
This paper should be no longer than 3000 words and written in APA style format.
Please use the APA 7th edition template linked from the PhD resources page.