Mother behavior items	Definition and examples
Positive affect	Caregiver demonstrates positive affect and emotional tone towards the child through facial expression (smiles, laughter), gestures (hugging), and voice.
Positive verbal	Caregiver makes encouraging statements of approval and affirmation towards the child, including praise and acknowledgement (e.g., “Good job!; I know it is difficult”), and other forms of positive reinforcement.
Responsiveness	Caregiver replies to child's verbal statements, questions, and nonverbal behaviors with contingent and appropriate responses. Examples include responding to the child's requests for help, handing over objects out of the child's reach as the child looks toward them, providing instructions that are keyed into the child's current focus and responsive to the child's initiations.
Participation	Caregiver is highly engaged with the child during the task, as expressed through behaviors such as sitting close to child, attending to the child's actions, and maintaining focus on the child and task during the entire session.
Structuring	Caregiver structures the task for the child so as to facilitate the child's performance. This includes indicating where materials are that the child needed, placing objects within reach of the child, handing the next object to the child, or verbally indicating steps to the process of completing the task.
Communication amount	Amount of talk or verbal statements caregiver makes to the child. High scores represent a caregiver who talks to the child throughout the session. This category does not consider the form of language caregiver provides, but rather the sheer amount of talk.
Explanatory language	When speaking to the child, the caregiver displays a style of communication that contains high use of descriptive and explanatory language, as characterized by high use of labels, adjectives, adverbs, and questions to child (e.g., “Those are the ingredients for the cake”; “Where do you think the red piece goes?”; “Which utensil should we use?”).
Directive language	When speaking to the child, the caregiver displays a style of communication that contains high use of imperatives (commands) and high use of pronouns rather than descriptive language (e.g., “Put that one there”. “Get that one”).
Negative affect	Caregiver demonstrates negative affect towards child through facial expressions (frowns, negative expression), gestures (pushing or pulling child), and voice tone (anger or harshness).
Negative verbal	Caregiver expresses disapproval towards the child verbally, including criticizing child (“You are making a mess”) and discouraging statements or discontent (“I don't like what you're doing”).
Intrusiveness	Caregiver displays high levels of control and intrusiveness during the interaction, by prohibiting child's actions, interrupting child's actions, and taking over the task. Examples include the caregiver hovering over the child, restricting the child's behaviors, taking objects away from the child, introducing new objects or actions while the child is engaged in something else, refusing to hand over objects to the child that are needed so that the caregiver can complete the project without the child actively participating.
Inflexibility	Caregiver is unable to “bend the rules” during interactions, and is inflexible by not accepting the child's initiatives. Examples include, insisting that the child engages in a particular activity selected by the mother, even if the child wishes to do something different, and not switching to a different strategy or task when the current strategy is not effective with the child.
Child behavior items
Positive affect	The child displays positive affect and pleasure when engaging in the task as expressed through facial expressions (smiles, laughter), tone of voice, body position, and gestures.
Language amount	Amount of talk or verbal statements by child during the session. High scores represent a child who is talkative throughout the session. This category does not consider the form of language, but rather the sheer amount of talk.
Communication style	Amount of talk or verbal statements child makes. High scores represent a child who is very verbal during the session by commenting on activities, asking for assistance or clarification, and speaking about non-task related topics.
Initiation	Child takes initiative in carrying through with the task, and seeks information/input/feedback from caregiver that is directed to the task, either verbally or through gestures. Examples might be a child pointing to the materials needed, or asking information about how to complete the task (“How do I crack the egg?”).
Task involvement	Child demonstrates interest and engagement with the task materials, both verbally (by talking about the task) as well as non-verbally (by attending to the task and manipulating the materials).
Activity level	Child displays high activity level during the task, which may be directed toward the caregiver or task, but might also reflect general arousal and lack a focus. Examples include child moving around, fidgeting, continually manipulating the task materials, etc.
Task persistence	Child seeks out and explores aspects of the task materials visually and manually. Child maintains visual attention to the task, remains focused on the task, and carries through with task activities.
Task competence	Child demonstrates competence in the task by successfully completing various steps to the task (e.g., cracking eggs, combining ingredients).
Responsiveness	Child responds to and cooperates with the caregiver during the interaction. Child is accepting of the caregiver's directions, for example by following through on what the caregiver suggests or verbally acknowledging the caregiver's suggestions (“Yeah, I'll do that”).
Participation	Child participates with the caregiver during the session, as expressed by verbal and nonverbal behaviors (e.g., talking to caregiver, looking at what caregiver is doing). The child initiates interactions with the caregiver (“How do you do this one?”; “Can you help me?”) as well as follows through with caregiver initiated actions.
Emotion regulation	The child is able to maintain self-regulation both in actions and emotions. Child remains focused on the task, is not easily distractible, and remains calm rather than upset or angry throughout the session.
Negative affect	Child demonstrates negative affect through facial expressions (frowns, negative expression), gestures, and voice tone (e.g., angry and/or generally unhappy, sad tones).