Evaluating a Targeted Selective Speech, Language, and Communication Intervention at Scale - Protocol for the 'Happy Talk' Cluster Randomised Controlled Trial.

This is a standardized norm referenced language assessment that yields standard scores for total language, auditory comprehension, and expressive communication. A standard score of 100 represents the performance of a typical child at a given age, the higher the standard score the better the performance. Standard scores between 85 and 115 correspond to one standard deviation below and above the mean, respectively; scores within this range are considered to be within normal limits.

The Focus on the outcomes of communication under 6 (FOCUS-34) is a clinical tool designed to evaluate change in communicative-participation in preschool children. The parent form consists of 34 statements - aimed at taking a snapshot of children's skills as they are on that day. Parents are asked to rate each statement using a 7 point scale, ranging from 'not at all like my child' to 'exactly like my child'. This yields a total score ranging from 50 to 350 with a higher score indicating a better outcome.

The Maternal Responsive Behaviours Coding Scheme (MRBCS - Levickis et al. 2014) is an observational coding scheme of parent- child interaction. Implementation of the MRBCS yields a total number of occurrences of one of four parental responsive behaviours (Expansions; Imitations; Responsive Questions; and Labels), for a given period. By summing the frequency scores for each behaviour, an overall score of parental responsiveness can be calculated. The lowest score is 0 and the highest score is not specified. The higher the score the greater the number of parental responsive behaviours - yielding better outcomes.

This is a parent proxy-report scale of health-related QoL in young children. The PedsQL for toddlers contains 21 items and measures four health dimensions: physical, emotional, social, and school functioning (questions related to school or daycare if attended). The tool asks, "please tell us how much of a problem each item has been for your child during the past one month." Parents are required to rate each item on a scale of 0- 4 (0 indicating never a problem and 4 almost always a problem). The ratings are tallied yielding a total score for each section, the higher score indicating a greater level of difficulty.

The Classroom Assessment Scoring System (Pianta, La Paro, & Hamre, 2008) is a theoretically-based and empirically-supported observation instrument designed to assess the quality of interactions between teachers and students in the classroom. The CLASS measures three broad domains of teacher-student interactions: Emotional Support, Classroom Organization, and Instructional Support. These three domains are comprised of 10 specific dimensions of teacher-student interactions. Assessors assign scores to classrooms on each of the 10 dimensions on a 7-point scale.

This is a parent proxy-report scale of health related quality of life in young children. The CHU9D for children < 5years) consists of 11 questions and parents are asked to base their responses on how their child is feeling on the day of completion. It consists of a descriptive system and a set of preference weights, which give utility values for each health state described by the descriptive system, allowing the calculation of QALYs.