Table 2.

Brief summary of study timeline

Milestone	Timing
Main trial phase study set-up	April to September 2017
Sites 1 and 2
Identification of potentially eligible participants	October to December 2017
Recruitment and baseline and data collection	November 2017 to January 2018
Intervention participants receive Incredible Babies book	November 2017 to January 2018
Follow-up one data collection	January to February 2018
Delivery of Incredible Years Baby Programme	March to May 2018
Follow-up two data collection	August to September 2018
Delivery of Incredible Years Toddler Programme	January to March 2019
Follow-up three data collection	May 2019 to June 2019
Process evaluation interviews and focus groups	July 2019
Sites 3 and 4
Identification of potentially eligible participants	May to July 2018
Recruitment and baseline and data collection	June to August 2018
Intervention participants receive Incredible Babies book	June to August 2018
Follow-up one data collection	July to September 2018
Delivery of Incredible Years Baby Programme	October to December 2018
Follow-up two data collection	March to May 2019
Delivery of Incredible Years Toddler Programme	September to November 2019
Follow-up three data collection	December 2019 to January 2020
Process evaluation interviews and focus groups	February 2020
Final report	July 2020