Table 3 Outcome measures for all the three WPs

Work package—I

• Establishing sensitive and feasible echo parameters for detecting right ventricle dysfunction associated with early BPD pulmonary vascular changes

• Suitability of eligibility criteria and sample characteristics

• Fidelity to the study procedures such as recruitment, data collection including echo scan performance at the set time points

• Recruitment, accrual, and retention rates

Work package—II

• To gain an understanding of how strong the correlation between the parents’ views of their infant’s health development during the first 10 days of postnatal life and the findings of echo scans at the same period

Work package—III

• To gain an understanding of parents and healthcare professionals in participating in the study and identify barriers and enabling factors to inform the methods a full trial