Study Goldsmith & Campos (1990): study US Denver, Colorado
- Public
 - 9 months aged, infants, Denver, United States, 198?
 - Survey name
 - Unnamed study
 - Sample
 - Respondents
 - N = 168
 - Non Response
 - Assessment
 - 
        Behavioural observation                    
Twins were assessed with the other twin present in room. Mother & father completed Infant Behavior Questionnaire (IBQ) independently from one another at home. 
Correlate
- Authors's Label
 - Activity level
 - Our Classification
 - 
            
 - 
                        
 - Remarks
 - Part of Rothbart Infant Behavior Questionnaire (IBQ), Same rating scale as the "Smiling and Laughter" measure of happiness
 - Distribution
 - paternal data: N=128; maternal data: N=143
 - Operationalization
 - Mother's & father's reports on child's gross motor activity, including
- movement of arms and legs
- squirming
- locomotor activity
Each rated:
1 never
2 very rarely
3 less than half the time
4 about half the time
5 more than half the time
6 almost always
7 always
Full list of situations not reported 
Observed Relation with Happiness
maternal report: r=+.05