References for Pragmatics
Fujiki et al, LSHSS 1/2013 A Social Communication Intervention to Increase Validating Comments by Children With Language Impairment This study looks at delivering services to target students in a small play group with typical peers for 10 week course; 3/4 target students showed increase in use of validating comments . Likability ratings were also considered ; no significant change in peer ratings, but teachers did apparently notice & appreciate increased positive output. This study does have a nice rundown of different types of comments.