3.2.1. Interactional Structure

Turns. The communication partners produced more communicative turns within the interaction compared to children/youths with complex needs (*F* = 13.87, *p* = 0.001). The difference in turns between the partners and children was not significant in the EGAT condition (estimated mean difference = 1.71, *p* = 0.56) but was significant in the NEGAT condition (estimated mean difference = 3.15, *p* = 0.04) from the Bonferroni analysis.

Moves. Slightly more initiations were found when children used EGAT in communication compared to the NEGAT condition (mean = 1.16 vs. 0.43, *t* = 2.26, *p* = 0.07). However, according to Table 5, R/I and F/I were not frequently found in the children, probably because of the difficulties these children had in conducting dual-purpose moves. Therefore, we collapsed I, R/I, F/I into a category representing all "initiations" because these moves all introduced a topic and/or requested responses of their own, and "initiations" were one of the most important aspects of communication for these children. Children made significantly more "initiations" when they used EGAT compared to the NEGAT condition (mean = 1.30 and 0.43, respectively, *t* = 2.60, *p* = 0.0485). In addition, the results of the analysis indicated that children made fewer response moves in the EGAT condition compared to the NEGAT condition (mean = 2.41 and 3.87, *t*= −4.76, *p* = 0.005). The partners made significantly fewer initiations (mean rate per minute = 1.97 vs. 3.87, *t*= −2.74, *p* = 0.04) in the EGAT condition compared to the NEGAT condition.

#### 3.2.2. Communicative Functions

No significant differences were found in the frequency of different categories of communicative functions used by children between the two conditions. However, of marginal significance was a finding that showed children had higher frequencies of providing information in the EGAT condition compared to the NEGAT condition (mean = 2.53 vs. 1.34, *t* = 2.04, *p* = 0.097). The partners made significantly fewer requests (mean = 3.51 vs. 5.16, *t*= −3.37, *p* = 0.02) in the EGAT condition compared to the NEGAT condition. The results also showed that they mostly dominated the conversation by asking closed-ended questions (mean = 2.56 vs. 4.26 in the EGAT and NEGAT conditions, respectively).
