Table 1.

Descriptions of Observational Rating Systems

Variable	Description	Ratings1
Maternal Behavior
Warmth	Positive affect (smiling, laughing) expressed toward the infant.	1 = none; 2 = a little; 3 = some; 4 = a lot
Involvement	Degree to which the mother attended to and engaged with the infant.	1 = minimally; 2 = somewhat; 3 = moderately; 4 = consistently
Sensitivity	Responding appropriately and promptly to the infant’s cues.	1 = minimally; 2 = somewhat; 3 = moderately; 4 = consistently
Hostility/  Irritability	Negative expressions, including annoyance, critical comments, angry teasing and sharp or harsh tone of voice.	1 = none; 2 = a little; 3 = some; 4 = a lot
Intrusive Behavior	Poking, pulling, lunging face or hands close to the infant’s face, and/or loud or high-pitched vocalizations.	1 = minimally; 2 = somewhat; 3 = moderately; 4 = consistently/highly
Mental State Talk	Relative frequency of comments that attribute skills, intentionality or abilities to the baby, reflecting a belief that baby could play an active role in, or have an impact on, the environment (e.g. “You think that’s funny?”, “You talking to mama?”, “You just want to go home”)	1 = none; 2 = 1–2 comments, rare relative to rest of the mother’s speech; 3 = 3–5 comments, comprise less than half of mother’s speech; 4 = 5 or more comments, comprise more than half of mother’s speech
Infant Behavior
Positive Affect	Frequency and duration of positive facial expressions or vocalizations.	1 = none; 2 = 1–2 brief displays; 3 = several brief displays; 4 = several prolonged/intense/heightened displays; 5 = frequent prolonged/intense/heightened displays
Negative Affect	Frequency and duration of negative/distressed facial expressions or vocalizations.	1 = none; 2 = 1–2 brief displays; 3 = several brief displays; 4 = several prolonged/heightened displays; 5 = frequent prolonged/heightened displays
Gaze to Mother	Frequency and duration of infant looks to mother’s face.	1 = none; 2 = 1–2 fleeting looks; 3 = 3–4 fleeting looks or 1–2 longer looks lasting 10 seconds or more; 4 = 3 or more longer looks; 5 = Frequent/prolonged looks

Notes.

¹Descriptions provided here are meant to be brief summaries of rating system and do not include the full level of detail used for ratings.