Study Froh et al. (2009a): study US 2006
- Public
 - 8-19 aged participants in a gratitude intervention and controls, USA, 200?
 - Survey name
 - Unnamed study
 - Sample
 - Respondents
 - N = 89
 - Non Response
 - Assessment
 - Questionnaire: Paper & Pencil Interview (PAPI)
 
Correlate
- Authors's Label
 - Gratitude intervention
 - Our Classification
 - 
            
 - 
                        
 - Distribution
 - 1: 50 %
 - Related specification variables
 - 
                
 - 
                            
 - Operationalization
 - Students were randomly assigned to
1 GRATITUDE INTERVENTION. Students were directed to express their gratitude to a person that has been especially kind to them. They had to write a gratitude letter and deliver the letter personally in a face tot face meeting.
O: CONTROL. Students had to write down some of the things they did yesterday and what they felt like doing these things. 
Observed Relation with Happiness
T1-T2 T1-T3 T1-T4
- Gratitude group + 1.8 0.0 - 0.8 (ns)
- Control group + 2.7 - 0.9 - 0.6 (ns)
Difference - 0.9 + 0.9 - 0.2 (ns)
- Control group +2,3% - 0.8% -0.5%
Difference -0.8% + .08% -0.2%
Happiness assessed at:
T1: pre-test
T2: post-tst
T3: 3 week follow up
T4: 2 month follow-up
Affect Balance computed by WDH team substracting average negative affect from average positive affect