The most powerful predictor for the difference between the dimensions of the language was the age of the child; However, the direction of this association varied for each cohort. Parents of older children in the Language for Learning cohort tended to report higher values on measures reported by parents, while parents of older children tended to report higher rates for direct action in the Early Home Learning Study cohort. Previous studies have shown that parents` ability to accurately account for changes in their child`s language can deteriorate as children age and their vocabulary expands and language use becomes more complex (Law and Roy, 2008). The differences between these cohorts may also be due to the child`s age groups (24 months or 6 to 36 months) and the nature of the measures selected. For example, parents of children under 18 months of age who participated in the early learning study at home were asked about a receptive and expressive vocabulary. In addition, the Early Communication Indicator assessed only observable characteristics such as gestures, vocalizations, individual words and multiple words. Apart from this, it is remarkable that the age of the child given the age of the child (M – 24.4 months; SD – 1.1 months). At this young age, the language evolves rapidly and a short time can lead to very different language notes. This finding highlights the complexity of language measurement in young children and the importance of selecting age-specific measures based on years and months. The ILC is a short, reliable and frequent measure of children`s language skills (Fenson et al., 2000). One in three versions was used in months depending on the age of the child.
The ILC`s abbreviated form level I was used for children under 18 months of age, including a list of 89 words, resulting in a total score of 0 to 89. Parents were asked whether their child “understands” or “understands and says” each word. Parents of children aged 19 to 30 months have completed the second cycle. Parents were asked if their child “says” 100 words listed, giving a total score of 0 to 100 for word production and a single element of evaluation of word combinations.