5.2.1.1 Screening phase
Ethical approval for all studies in the present thesis was obtained from the UCL Research Ethics Committee. An opportunistic sample of 502 full-time university students (217m, 285f), who were fluent in English and aged 18 or over, was recruited for the screening phase of the study. All participants provided informed consent before completing the PPI-SF (Lilienfeld and Hess, 2001). As an incentive, participants were entered into a prize draw and informed that they might be invited to a second stage of the study, for which they would receive payment.
The PPI-SF (Lilienfeld and Hess, 2001) is a self-report questionnaire designed to measure personality traits central to the construct of psychopathy, for example egocentricity, impulsivity, cold-heartedness, capacity to manipulate and fearlessness. The PPI-SF consists of 56 statements on a 4-point, Likert-type scale with ‘False’, ‘Mostly False’, ‘Mostly True’and ‘True’as possible responses; higher scores indicate higher degrees of psychopathy. In order to ensure consistent responding, questionnaire items are counterbalanced such that psychopathic traits are associated with agreeing with half the statements and disagreeing with the remaining half. The PPI-SF total score has been found to have good internal consistency (Cronbach’s alpha .85) and correlates well with the full version of the PPI (r= .90).
Total PPI-SF scores were calculated for the whole sample. In order to select the high and low psychopathic trait groups for the testing phase, participants scoring at the highest and lowest ends of the sample distribution were systematically contacted (i.e. starting with the highest scorer and moving lower for the high trait group, and starting with the lowest scorer and moving higher for the low trait group). Thus, 98 participants whose scores fell within the upper and lower tenth percentiles of the sample distribution were contacted and invited to take part in the second stage of the study. This consisted of 47 individuals (26m, 21f) in the upper range and 51 individuals (11m, 40f) in the lower range.
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5.2.1.2.1 Design
A between-groups design was used to compare high-PPI and low-PPI participants.
5.2.1.2.2 Participants
Of those contacted from the screening phase, 20 high-scoring (10m, 10f) and 19 low-scoring (4m, 15f) individuals agreed to take part in the testing phase of the study. As anticipated, the groups differed significantly on PPI-SF scores, t(38)=22.64, p< 0.0001; the mean scores were 154.1 (SD 8.14) and 98.10 (SD 7.26) for the high and low groups respectively. The groups did not differ significantly in age, t(38)=1.52, p =0.137; the mean ages were 19.85 years (SD 1.60) and 21.00 years (SD 2.96) for the high and low groups respectively.
5.2.1.2.3 Procedure
All participants provided written informed consent before completing the Social Strategy Task and a brief health screen to ensure that nobody with a history of significant psychiatric or neurological illness was included; no participants were excluded on this basis. Participants were paid for taking part.
5.2.1.2.4 Materials
5.2.1.2.4.1Social Strategies Task
The Social Strategies Task (Channon et al., 2012) consists of 10 vignettes, each describing everyday social situations in which a character known to the participant (i.e. friend, relative, colleague or neighbour) poses an awkward question involving asking the participant for a favour or a favourable opinion. The gender of the main characters, the type of relationship and the social context varied across scenarios. Presentation of the materials was randomly counterbalanced such that half of each group (high versus low) were shown a different order of items to control for order effects.
The social strategy scenarios were designed to pit self-interest against consideration for others, giving the opportunity to study participants’ priorities in situations with no right or wrong answers. Each scenario description made it clear that it was in the main characters’ interest to get participants to comply with their requests, and in the participants’ interest not to comply, since compliance would necessitate incurring a personal cost of some kind. The task required participants to decide the extent to which they would comply with requests and
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how they would communicate these to the main characters. See Figure 5.1 for example scenario.
Figure 5.1: Example scenario from Social Strategies Task
______________________________________________________________________ Story stem
“Your cousin likes to come and stay with you. She is good company but when she visits she expects you to pay to take her out to expensive places.”
During a phone call she asks: “Can I come and visit you next weekend?” Questions for each scenario
1. What would you say in this situation?
2. On a scale of 0 to 100, where 0 represents ‘not at all awkward’ and 100 ‘extremely awkward’, how awkward would you say this situation is?”
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5.2.1.2.4.2 Administration
After reading the instructions, participants were given an instruction sheet, shown an example item, and allowed to ask questions. All scenarios and corresponding questions were then presented one at a time, in a paper booklet. Participants responded verbally to all questions. The scenario remained on display until participants had completed the relevant questions in order to reduce the confounding effects of memory load.
5.2.1.2.4.3 Scoring
Strategy Usage. For each scenario, verbal responses were described as positive (i.e. prosocial) if they complied at least partially with the main characters’ requests, and negative if they did not comply. There were three categories each for positive and negative strategies; these were counted for each participant, and calculated as percentage scores.
Positive responses were classified into one of three categories, according to the degree of prosocial behaviour:simple acquiescence, qualified acquiescence with an excuse, and qualified acquiescence with negative feedback. Simple acquiescence referred to responses in which participants agreed to the characters’ requests without qualification (e.g. ‘yes you can stay with me). Qualified acquiescence with an excuse referred to responses in which they partially or conditionally agreed to the character’s request, with an excuse based either on altering the interpretation of the behaviour of the main character to a more favourable one or an excuse based on the participant’s difficulty in complying fully (e.g. ‘Yes, come along
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but this time I’d like to stay home and have dinner because its cosier than a restaurant’).Qualified acquiescence with negative feedback implied criticism by making direct reference to some undesirable aspect of the main character’s behaviour as a justification for lack of full compliance (e.g. Yes, but I expect you to pay your share of whatever we have to pay for).
Negative strategies were classified into one of three categories, depending upon the degree of prosocial behaviour: justified refusal with an excuse that protected the main character’s feelings (e.g. Sorry but I’ve got other plans that weekend, maybe some other time), justified refusal with negative feedback that implied criticism of the main character (e.g. No, I can’t afford to keep taking you out), and outright refusal. Outright refusal strategies consisted of simple refusals to comply with the character’s request (e.g. No you can’t visit next weekend).
Perceived awkwardness. Awkwardness ratings were averaged across the ten scenarios.