First, the kitten or cat and their human caregiver were placed together in a room, with the human sitting in a marked circle. If the cat entered the circle, the human could interact with it. After two minutes, the human left, leaving the cat alone. After another two minutes, the human returned to the room, to sit in the circle again.

The entire test was filmed, and the scientists analysed the video to classify the cats’ attachment type.

The adult cats only participated in the test once, but the kittens were tested twice – once initially, and once again two months later, after 39 of the kittens had been through a six-week training and socialisation course. The other 31 acted as a control group.