Mulac 1977.

Methods	Randomised Controlled Trial
Participants	9 participants aged 4;04 ‐ 6;03 6 males and 3 females participated, no details of SES are given
Interventions	Clinician administered Monterey operant language programme with additional outdoor activities and home activities for the children in the programme and additional lessons condition. On average children received 67 minutes of therapy a week for 4 weeks. Focus of the intervention was on 'is' interrogative 3 children received articulation therapy 3 children received Monterey language programme 3 children received Monterey language programme and additional exercises to facilitate generalisation
Outcomes	Extra clinic measures of 'is' interrogative measures
Notes	Focus on the generalisation of 'is' interrogative Children only had to fail this component in order to be included in the study.
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment (selection bias)	Unclear risk	B ‐ Unclear