Pretest The final stage in questionnaire development is the pretest: the dress practice of the study. Inattentive of the time, money and effort spent to develop a questionnaire, the perform can out of a planned. An amount of pretest trials cannot guarantee decided very much. Instead, the pretest should be repeated with new subjects until the researcher is satisfied. The conditions should be identical to those of study, including the choice and of subjects There is no formula to determine the number of subjects required. Some investigators have stated more than 10 subjects for each pretest is sufficient. Therefore, the decision on the sample size is subjective and is influenced by availability of subjects