Table 1:

Abbreviated codebook

Code	Definition	Example(s)
Uncertainty	Statement indicates that the discussant is unsure about the presence or absence of dystonia	‘I think I see …’ ‘I’m hedging’
Unilateral	Specific mention of the movement feature occurring in one limb	‘… the left foot looks …’ ‘… his right leg does …’
Variability over time	Statement is about features occurring in just one portion of the video but not in other portions of the video	‘Her right foot initially turns in more and then straightens out in the end’ ‘It disappears later on’
Subtle	Discussant acknowledges that a movement feature is difficult to see or of low amplitude	‘He’s got a little bit of crouch’ ‘It’s just so mild’
Adduction	Either the leg or foot is noted to come towards the midline	‘That left leg crosses in’ ‘The left knee comes in’
Need chart information	Discussant expresses the desire for additional information about the participant to help with dystonia identification	‘How old is she?’ ‘I want to know her diagnosis’
Abnormal movement, non-specific	A movement is mentioned as being abnormal but not further characterized	‘That’s a funny posture’ ‘I would call something in her feet’
Selective dorsal rhizotomy	Discussant ponders whether or not the child has had or would benefit from a selective dorsal rhizotomy	‘This patient has had a rhizotomy maybe’ ‘I just feel like a lot of our rhizotomy patients will have a gait that looks like that several years later when they get bigger’
Foot	The foot is mentioned explicitly
Leg	The leg is mentioned explicitly