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Average number of different semantic content categories across age groups.
| Age group 1 | Age group 2 | Age group 3 | |||||||
| Mean | S.D. | Range | Mean | S.D. | Range | Mean | S.D. | Range | |
| Number of different semantic content categories | 14.5 | 2.2 | 9–19 | 16.5 | 1.90 | 13–20 | 16.4 | 1.40 | 14–19 |
