PSYCHOLOGICAL TESTS 
ALTERNATIVE FORMS 
Alternative forms of a test are ordinarily indispensable 
in order to reduce the possibility of coaching or cheating. 
These forms should be equal in difficulty and should corre- 
late highly (over .95) with each other. The best procedure 
for devising alternative forms of a test is to divide a large 
list of acceptable items into several piles purely by chance. 
Then by preliminary trial their actual relative difficulty 
can be determined with precision. 
When a battery of tests is used, the forms may, for con- 
venience, be fastened together, or printed as a booklet. They 
should be arranged so that only one test appears at a time, 
the easiest tests at the beginning, and others following in 
order of difficulty. A very easy and interesting test may be 
included with no intention of scoring it but of using it 
merely as a shock absorber, to put the subject at ease when 
he begins. Tests which do not require timing may be placed 
at the end, then the booklet may be handed in when com- 
pleted. Instructions should specify that no one is to turn 
back to a preceding test. 
The construction of psychological tests for the measure- 
ment of abilities is a complicated matter calling for a high 
degree of ingenuity and sound judgment, as well as a fa- 
miliarity with the principles outlined in this chapter. No 
amount of foresight can anticipate all the complications 
which may upset a smooth-running test performance. The 
investigator will find it necessary to try out his tests on a 
few subjects before putting them in final form, in order to 
correct unforeseen obscurities or sources of misunderstand- 
ing in the directions or in the body of the test. 
Before treating of the problems arising in the administer- 
ing of tests of abilities, chapters will be devoted to an instru- 
ment for the systematized estimation (rather than measure- 
ment) of abilities—the rating scale, and to an instrument 
for gathering factual data—the questionnaire. 
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