The 3rd edition of the ELOM Technical Manual includes important additions. Firstly, the test-retest reliability and concurrent validity of the ELOM Direct Assessment have been established in recent research, and are reported in Chapter 5.
Test-retest reliability measures the stability of a child’s scores when measured on two different occasions within an age-appropriate period. The scores should not vary. In this research the same children were tested one week apart. Excellent test-retest reliability was evident for ELOM Total scores.
Concurrent validity is also an important property of an instrument such as the ELOM. It establishes whether scores on a new test that purports to measure a particular construct, correlate with an established and reputable measure of the same construct. To investigate this, the same group of children were tested on the ELOM and on the Wechsler Preschool and Primary Intelligence Scale (WIPPSI-IV) on the same day. The latter instrument assesses the cognitive functioning of children in the same age group as the ELOM. It is not standardised in South Africa. High concurrent validity was observed between WIPPSI-IV Full Scale Composite scores, and ELOM Total scores. Both recent studies provide further evidence of the psychometric quality of the ELOM Direct Assessment.
And then finally, the ELOM Teacher Assessment now has its own Chapter (7). Its concurrent validity was investigated in a large sample of children that were rated by their teachers on the Teacher Assessment and on the comparable and well-established Strengths and Difficulties Questionnaire (SDQ). Sound concurrent validity was established indicating that the Teacher Assessment can be used with confidence to assess the quality of children’s social relations with adults and peers, and their emotional readiness for school. Further investigations have strengthened the criteria for acceptable scores on the two subscales of the Teacher Assessment.