Differential diagnosis of ability in school children / by David Segel.

  • Segel, David.
Date:
1934
Catalogue details

Licence: In copyright

Credit: Differential diagnosis of ability in school children / by David Segel. Source: Wellcome Collection.

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    original correlations in calculating +/2 — 2ri,. of the ratio V2 — ri— rer or 2a. 4/2 — 2r 12 Od In this section the methods for determining the efficiency of tests for marking a differential diagnosis have been given. It is necessary to subject batteries of tests and ‘‘diagnostic” tests to the technique described in order to be certain that the tests actually do differentiate between the abilities and skills for which scores are given. The direction of instruction and guidance based upon tests, the differential diagnostic value of which are unknown, may be in many cases wrong. It cannot be emphasized too strongly that tests should be evaluated before being chosen for use as instruments of differential diagnosis.