QUESTIONNAIRES
tional interest analysis given in Figure 15 (57, 58) illustrates
 this point.
The data of the questionnaire are easier to tabulate if
the questionnaire is printed so that answers are in a column
near the right-hand margin of the page.
It is impossible to insure against falsification of answers,
but the probability of obtaining the truth is increased by
arranging the questions so that the most profitable direction
of falsification is difficult to guess. The vocational interest
questionnaire given above illustrates this point. This questionnaire
 ordinarily reveals whether the applicant’s vocational
 interests are scientific, literary, social, solitary, outdoor,
 indoor, professional, or commercial. If the vocations
were grouped in this way instead of being in alphabetical or
apparently haphazard order, the applicant would quickly
suspect the purpose of the blank and would probably censor
 his answers. The purpose of the questionnaire is best
achieved by its present arrangement which prevents this
purpose from being obvious.
Any single questionnaire should be brief. If a great
amount of information is wanted, the questions should be
arranged in a series of questionnaires each covering a
specific type of information. The worker may be given one
questionnaire at a time in order not to overwhelm him by
the mass of information required.
OBTAINING THE DATA
If the subjects of the investigation are applicants the experimental
 questionnaires may be filled out by the applicant
himself or by the interviewer for him. The former arrangement
 saves time, but unless the interviewer is accessible the
applicant will not be able to have matters explained which
puzzle him. Except in dealing with the most intelligent
employees it is safest for the interviewer to check over the
questionnaire with the applicant after it has been filled out.

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