Table 3.

Likert scale to score the mother–infant interaction intensity during the collections

Score	Definition: During the before‐Kangaroo care saliva collection, there was:
0	Maternal absence
1	Maternal presence but silent and without touching
2	Maternal presence, her voice was audible but speech not directed at infant
3	Maternal presence including infant‐directed speech
4	Maternal presence plus some touching of for instance the head

Score	Definition: During the during‐Kangaroo care saliva collection:
0	Mother seemed somewhat stressed or distant towards the infant
1	Mother was not stressed, but provided no extra vocalisations or caressing
2	Some infant‐directed vocalisations and extra caressing was provided
3	Frequent infant‐directed vocalisations and extra caressing was provided
4	Constant infant‐directed vocalisations and extra caressing