Table 3. Detailed description of all behavioural variables measured in 11 subtests in MVCCB 2.

Name of subtests	Variables coded	Type of variable	Description	Inter-observer reliability (Cronbach’s alpha/ Cohen’s kappa)
Exploration	Exploration	Percentage time	Dog was moving/standing in the room and had its nose on or in close proximity (approx. 5 cm) to the floor/wall/object/s or both front paws placed on an elevated surface (e.g., window sill, table).	0.95
	Locomotion	Percentage time	Dog was moving in the room with or without any directed activity.	0.99
	Inactive	Percentage time	Dog was inactive (sitting/standing/lying).	0.99
	Position at O_1m	Percentage time	Dog was standing/sitting/lying or moving within 1m of O.	0.94
	Looking at O	Percentage time	Dog’s head and eyes were orientated towards O (dog was moving or stationary).	0.97
Picture viewing	Follow O	Duration	Dog was moving in the direction of the moving O or stationary O.	0.95
	Move independent	Duration	Dog moved independently of O.	0.90
	Position at O_1m	Duration	Dog was standing/sitting/lying or moving within 1m of O.	0.96
	Looking at O	Duration	Dog’s head and eyes were orientated towards O (dog was moving or stationary).	0.94
Food choice	No. of correct choices	Frequency	Number of times the dog chose the plate with sausage in both step1 and step2.	100
Separation	Position at door	Duration	Dog was positioned within the semi-circle in front of one of the two doors.	0.96
	Look at door	Duration	Dog was sitting/standing/lying outside the semi-circle but looking at one of the two doors.	0.98
	Locomotion	Duration	Dog was moving in the room with or without any directed activity.	0.98
	Exploration	Duration	Dog was moving/standing in the room and had its nose on or in close proximity (approx. 5 cm) to the floor/wall/object/s or both front paws placed on an elevated surface (e.g., window sill, table).	0.97
Greeting and Playing	Latency to approach S/O	Latency	Measured from the moment the dog approached S/O within 20cm after S/O entered the room and stood by the door.	0.99
			This variable was coded separately for S and O.
	Greeting (S/O)	4-point scale	0: dog did not approach/approached initially but then avoided (with no interaction with S/O). 1: slowly sniffed or passively stood after approaching S/O with or without tail wagging. 2: friendly greeting, tail wagging, may have cuddled up, jumped or licked. 3: very excited/enthusiastically greeted with intensive searching for contact and tail wagging.	0.98 Cohen’s kappa
			This variable was coded separately for S and O.
	Playing (S/O)	4-point scale	0: no play. 1: mouthed toy sometimes but did not play/ may have played after a while but needed some encouragement. 2: mouthed toy and sometimes pulled it/brought it back. 3: played more than 90% of time.	0.99 Cohen’s kappa
Memory test with distraction	Latency to find food	Latency	Measured from the first detectable forward movement of the dog (after O removed the lead) until the dog found the food.	0.99
Detour	Latency to success	Latency	Latency to get the reward in trial 1, 3 and 4. This variable was coded separately for each trial.	100
	Time close to gate	Duration	Duration of time dog stayed close to the gate (the head of the dog was within 50 cm of the gate) in trial 1, 3 and 4. This variable was coded separately for each trial.	0.98
	Looking at E	Duration	Duration of time dog looked at E in trial 1, 3 and 4. This variable was coded separately for each trial.	0.98
	Looking at O	Duration	Duration of time dog looked at O in trial 1, 3 and 4. This variable was coded separately for each trial.	0.98
Attention	Time looking at toy/human (E)	Duration	Total duration of time the dog looked at the moving toy/human (E). This variable was coded separately for the toy and human condition.	0.98/0.98
	Time looking at O	Duration	Total duration of time dog looked at O. This variable was coded separately for the toy and human condition.	0.97/0.98
Novel action	Latency to pull out board	Latency	Measured from the point when the yellow board was visible until the dog pulled out the board and ate the sausage in trial 1.	100
Manipulative persistency	Manipulate toy	Percentage time	The toy was pushed or moved with the dogs’ nose or paw (only actual contact with the toy was measured) in step 1 and step 2 separately.	0.95
Clicker training for eye contact	Latency to eye contact	Latency	Measured from the moment the dog had taken the sausage into its mouth until the dog looked up into the face of E. The average of the first 3 trials and average of the last 3 trials were measured as separate variables.	0.96
	Latency to find food	Latency	Measured from the moment the piece of sausage left E’s hand, until the dog found the food, and took it into its mouth. The average of the first 3 trials and the last 3 trials were used as separate variables.	0.72