Brendgen et al (2005): Contemporary study - Aim, method Flashcards
(15 cards)
What are the aims of this experiment?
- To see if social aggression can be caused by genes or environment
- To see if social aggression shared same cause as physical aggression
- To see if 1 type of aggression leads to another
Who was the sample?
- 234 6 year old twin pairs
- 44 MZ makes + 50 MZ females
- 41 DZ males + 32 DZ females
- 67 mixed sex DZ twins
Where was the sample taken from?
Quebec Newborn Twin Study in Canada
When and how was the data gathered that researchers focused on in this study?
Data from sample gathered longitudinally (can spot trends + patterns), at 5, 18, 30, 48, and 60 months, then again at 6 years
What did the data consist of?
2 ratings of each twins behaviour - one by teacher + one by classmates
When were the ratings gathered?
In spring term of school year to ensure twins were well known by those providing ratings of behaviour
What did the teachers rate? And what on?
Social + physical aggression on a 3 point scale (0 = never, 1 = sometimes, 2 = often)
What were the questions asked to teachers?
Social aggression = To what extent does the child spread nasty rumours about others?
Physical aggression = To what extent does the child hit, bite, or kick others?
How were peer ratings done?
Kids given booklet individually with pics of classmates + asked to nominate 3 kids on 1 page who best matched description of behaviour
Did same for every other page
What did the research assistant check?
That each child could recognise everyone in their class
What were the 2 descriptors of social aggression asked in peer ratings?
- ‘Tells others not to play with a child’
- ‘Tells mean secrets about another child’
What were the 2 descriptors of physical aggression asked in peer ratings?
- ‘Gets into fights’
- ‘Hits, bites, and kicks others’
How many twin pairs did + didnt attend same classroom?
175 pairs didnt, 59 pairs did
Can test environmental influence
What type of study was this?
Longitudinal (studied over long period) - Recruited from birth between nov 1995 and july 1998
How many minutes were given for testing per class?
45
