Regardless of the type of data collected, researchers and efficacious IT managers must attend to sampling (how will subjects be selected) and they must ensure the instruments they are using are both valid (measuring what they claim to be measuring) and sufficiently precise for the purposes. In addition, IT managers have a responsibility to gather data in an ethical manner. For example, they must ensure the privacy of subjects, ensure the data do not pose a threat to them, and they must have an option to withdraw also with providing informed consent. These issues are particularly important for the populations of students who are minors, and for who informed consent must be explained to parents or guardians as well. In some cases, it is preferred to have data collected by individuals who are not teachers or in other positions of authority in school.