Dr Ruth Tully (1) (2) & Dr Tom Bailey (1)

Transcription

1 Dr Ruth Tully (1) (2) & Dr Tom Bailey (1) 2017 (1) Research conducted whilst at The University of Nottingham, UK. (2) Tully Forensic Psychology Ltd, Nottingham, UK See: Journal of Criminological Research, Policy and Practice 3(1) doi: /JCRPP

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3 Paulhus Deception Scales (PDS) PDS (Paulhus, 1998): one of few deception scales available and validated in the field of legal, criminological, and forensic psychology. Socially Desirable Responding (SDR) Often used when administering tests where the client may gain in some way from performing well or badly. Forensic psychology often involves high stakes for a person e.g. liberty at risk. If assessor does not know extent of any deception, overall assessment may be biased. 3

4 Deception: more than a one factor model Paulhus: early deception scales based on oversimplified 1-factor model. PDS has 2 subscales: Impression Management (IM, 20 items) & SelfDeception Enhancement (SDE, 20 items). Paulhus: people can display one, both, or none of these styles of SDR. IM: response set state like tendency, controlling impression made on perceptions of socially acceptable responses in context, i.e. recognise shortcomings and fake good. SDE: response style trait like tendency towards. Person believes overly positive self-report. 4

5 Normative sample(s) Originally developed with an American and Canadian sample. Few studied specific to the UK, and those that use UK samples do not break down results so that norms can be utilised. Therefore, using the scale reliably in the UK requires UK sample validation: do the norms differ in the UK, and can we replicate the 2-factor model which has had mixed support over time. Some UK studies report offender norms (e.g. sample of sex offenders; Mathie & Wakling, 2011) but if we have no gen pop norm, how do we know how our client compares (i.e. non-clinical versus clinical norms)? Identified need for a UK general population sample to be analysed. 5

6 Is IM anti-social or normal? Research in this area suggests risk of deception being taken seriously by clinicians (e.g. Schamborg et al., 2015). Do we assume that high IM scores are anti-social, that the person is therefore high risk because they are being deceptive?... Deception is a feature of ASPD But in life, if we do not exhibit desirable behaviours, then e are at risk of not achieving desired outcome (Baumeister, 1982) think job interview, performance appraisal time! Yet the vigilance recommended in every case (Rogers, 2008) implies that IM in forensic contexts should be treated differently to that in non-forensic contexts. H1: IM is positively related to anti-social personality. 6

7 SDE and narcissism Paulhus original work utilised a narcissism scale to help develop the SDE but criticisms of this include suggestion of more than one type of narcissism e.g. covert and overt (see Rose, 2002) and thus have costs and benefits for a person. SDE developed to represent egotistical bias, unconscious inflation of qualities and conscious/deliberate enhancement of status. Narcissism therefore of interest in relation to SDE, and some links between narcissism and violence (Yu et al., 2012). H2: SDE is positively related to narcissism 7

8 Aims of study 1. To establish UK norms for PDS on gen pop sample. 2. To explore validity of the measurement model in terms of: 1. Dimensionality (i.e. model fit, psychometric properties); and 2. Predictive validity of IM for anti-social personality type and SDE for narcissistic personality type. 8

9 Method Data collected online (Facebook, LinkedIn, Twitter): Online samples diverse and representative (Gosling et al., 2010) Clicked Bristol Online Survey link comprising: Demographic items (age, gender, education level, work status) 40-item PDS (Paulhus, 1998) 20 IM Items, 20 SDE Items 77 item International Personality Disorder Examination (IPDE) screening version 7 Narcissism items, 9 Anti-Social items Attentional questions (removed 34 ppants) 9

10 Sample (n=321) Age range 18 to 77 (M = 34.71, SD = 11.92) 84.4% educated at degree level or higher 5.6% potential ASPD, 52% potential Narcissistic 10

11 Analysis Procedure Norms One Sample t-tests Measurement Validity Exploratory Structural Equation Modelling Confirmatory Factor Analysis Predictive Validity Structural Model 11

12 PDS UK general population norms Scale Original mean (SD) 6.70 (4.00) Impression Management Self Deception 2.20 (2.30) Enhancement Total SDR score 9.64 (5.11) UK mean (SD) 9.28 (4.58)* 2.09 (2.39) (5.31)* * Statistically significant p <

13 Measurement Validity ESEM IM construct had three sig. non-target item loadings (.31 to.45) SDE had four non-target item loadings (.22 to -.30) CFA Non-target loadings added to CFA (Booth & Hughes, 2014) Measurement model approaching adequate fit χ2 (732)=846.22(p<.001), CFI=.87, TLI=.86, RMSEA=.022 (90% CI s = ). Cross-loadings model better than CFA model without (χ2 (4)=44.87, p<.001) 13

14 Predictive Validity Structural Model addition of two direct paths IM to ASPD SDE to narcissism IM negative predictor of anti-social personality (β=.679, p<.001) contrary to H1 SDE positive predictor of Narcissism (β=.249, p<.05) Supporting H2 14

15 Discussion: UK norms Average total and IM scores significantly higher in UK sample than original sample. SDE score lower, but not significant. We should be using UK norms, otherwise risk client may be assessed as SDR or IM more than average, when in fact compared to UK gen pop they may not be. Consequences could include psychometric and self-report treated as invalid or not trusted, when may not be invalid. Use of norms that are not applicable to client raises ethical issues regarding psychometric test practice and interpretations. 15

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17 Discussion: Personality Higher IM scores significantly predicted lack of anti-social personality. This was despite IM being considered to represent deceit by Paulhus (1998) and deceit being part of ASPD (APA, 2013). Cannot be reasonably concluded that high IM = malicious or for anti-social purpose. Instead of stance of high IM invalidating other tests/self- report, collaborative approach recommended with clients to explore function of IM. 17

18 Discussion: Personality SDE scores were significantly associated with narcissistic personality. This confirms association between the 2 constructs with UK sample, as was the case with Paulhus (1998) sample. Therefore, assessment of SDE as trait like way of socially desirably responding could assist assessors in detecting narcissistic traits. Narcissism is a complex construct but this could be a start. Useful to be aware of as narcissism has been linked to violence in clinical and non-clinical samples (e.g. Lambe et al., 2016) 18

19 Limitations & Future Research Model fit for CFA could have been better Fit indices such as TLI decrease as no. items increase (Kenny & McCoach, 2003) Use alternatives to classical test theory e.g. IRT models? Self-ratings of Personality used Social desirability & faking Use observer assessments of personality? Internet Samples representative for norms? Internet omnipresent in Western society (e.g. PRC, 2012) Narcissism base rate quite high Use cut-off one point higher? 19

20 Future research and practice directions Correctional and psychiatric samples needed with comparisons to Paulhus (1998) as well as this UK gen pop sample. Examination of the 2 factors model is replicated with these samples. In practice, appropriate UK norm group comparison is recommended. Comparison to several groups may be appropriate. Consider why UK IM higher. Cannot assume high IM = antisocial, but high SDE may indicate narcissism. 20

21 Summary 2 factor model fit in UK sample. Total and IM scores significantly higher in UK than original sample - use UK norms for comparison. IM not anti-social. SDE may be indicative of narcissism. 21

22 References American Psychiatric Association (APA) (2013). Diagnostic and Statistical Manual of Mental Disorders, 5th ed. APA: Arlington, VA. Booth, T. and Hughes, D.J. (2014), Exploratory structural equation modeling of personality data, Assessment, Vol. 21 No. 3, pp Gosling, S.D., Sandy, C.J., John, O.P. and Potter, J. (2010), Wired but not WEIRD: the promise of the internet in reaching more diverse samples, Behavioral and Brain Sciences, Vol. 33 Nos 2/3, pp Kenny, D.A. and McCoach, D.B. (2003), Effect of the number of variables on measures of fit in structural equation modeling, Structural Equation Modeling, Vol. 10 No. 3, pp Paulhus, D.L. (1998). Paulhus Deception Scales (PDS): The Balanced Inventory of Desirible Responding-7:User s Manual. Multi-Health Systems Inc, New York, NY. 22

23 References Lambe, S., Hamilton-Giachritsis, C., Garner, E. and Walker, J. (2016). The role of narcissism in agression and violence: a systematic review. Trauma, Violence & Abuse. doi: / Mathie, N.L. and Wakeling, H.C. (2011). Assessing socially desirable responding and its impact on self-report measures among sexual offenders. Psychology, Crime & Law, Vol. 17 No. 3, pp , doi: Pew Research Center. (2012). Pew internet, internet adoption available at: (accessed 7 February 2016). Scamborg, S., Tully, R.J. and Browne, K.D. (2015). The use of the state-trait anger expression inventory-ii with forensic populations: a psychometric critique. International Journal of Offender Therapy and Comparative Criminology, Vol. 60 No. 11, pp , doi: / X