Genetic and environmental influences on verbal and nonverbal measures of the Big FiveIntroductionMethodParticipantsMaterialsNEO-PI-RFF-NPQProcedureResultsDiscussionAcknowledgmentsReferencesGenetic and environmental influences on verbal and nonverbal measures of theBig FiveMelissa Moorea, Julie Aitken Schermerb, Sampo V. Paunonena, Philip A. Vernona,*aDepartment of Psychology, University of Western Ontario, London, Ontario, CanadabManagement and Organizational Studies, University of Western Ontario, London, Ontario, Canadaarticle infoArticle history:Received 18 September 2009Received in revised form 30 January 2010Accepted 8 February 2010Available online 1 March 2010Keywords:Five-Factor modelBig FiveNonverbal personality assessmentBehavioral geneticsabstractThis study reports the first behavioral genetic investigation of a nonverbal measure of the Big Five and itsrelationship with a traditional verbal measure. Participants (N = 592 adult twins) completed the Five-Fac-tor Nonverbal Personality Questionnaire and the Revised NEO Personality Inventory. Monozygotic twinswere more alike on all domains of the Big Five as assessed by both sets of scales than were dizygotictwins, and univariate behavioral genetic model-fitting showed that individual differences in both thenonverbal and verbally assessed traits were entirely attributable to additive genetic and non-shared envi-ronmental factors. Positive phenotypic correlations were found between the same personality factorsassessed by the verbal and nonverbal measures and these correlations were themselves entirely attrib-utable to correlated genetic and correlated non-shared environmental factors. The results provide evi-dence for the validity of the newly-devised FF-NPQ.Ó 2010 Elsevier Ltd. All rights reserved.1. IntroductionPersonality traits can be viewed as a set of qualities that makepeople distinct from one another in terms of their assumed rolesor typical manners of behaving. Currently, the most popular con-ceptualization of personality structure is provided by the Five-Fac-tor model. The Five-Factor model comprises the personalitydimensions of Openness to Experience, Conscientiousness, Extra-version, Agreeableness, and Neuroticism. These five dimensions,the so-called Big Five, are held by many to provide a completedescription of personality.The Five-Factor model is often operationalized by the popularand widely-used Revised NEO Personality Inventory (NEO-PI-R;Costa & McCrae, 1992). The NEO-PI-R has well-established psycho-metric properties and has been used in numerous studies aroundthe world. This notwithstanding, one limitation of the question-naire is its reliance on the verbal representation of its items. A validnonverbal measure of the Big Five would have several advantages,for example allowing the exact same items to be used in cross-cul-tural investigations, or in assessments of dyslexics, immigrants,linguistic minorities, or illiterates who might not easily or validlybe evaluated with a verbal inventory. Fortunately, such a nonver-bal measure exists.Paunonen, Jackson, and Ashton (2004) constructed a nonverbalquestionnaire to assess the same five personality factors as as-sessed by the NEO-PI-R and its shorter sibling the NEO Five-FactorInventory (NEO-FFI; Costa & McCrae, 1992). The resultant inven-tory is called the Five-Factor Nonverbal Personality Questionnaire(FF-NPQ). For each Big Five domain, Paunonen et al. created a 12-item nonverbal scale, where each item consists of a line drawingof a central character performing a trait- or factor-relevant behav-ior in a specific situation. Respondents are asked to consider eachitem and to indicate, using a 7-point rating scale, the likelihoodthat they would engage in the type of behavior depicted in theillustration. Because the production of the FF-NPQ was based onthe measures used in the NEO-FFI and the NEO-PI-R, it should bethe case that ratings of the factors on the FF-NPQ correlate posi-tively with ratings of the same factors on both of those verbalinventories.Hong, Paunonen, and Slade (2008) employed a multi-trait-mul-timethod analysis to investigate the construct validity of three BigFive personality questionnaires: the NEO-FFI, the FF-NPQ, and a 50item-bipolar adjective rating form. Their results suggested that,regardless of the modality of item representations, the three differ-ent inventories have construct-valid properties and capture essen-tially the same five factors of personality. Paunonen (2003) usedthree different measures of the Big Five factors of personality topredict a variety of criterion variables thought to represent behav-iors of some social and cultural significance. Using the NEO-FFI, theNEO-PI-R and the FF-NPQ, results indicated substantial consistencyin behavior predictions across the different instruments. Further-more, there was little evidence that the verbal forms were moresimilar to each other in predicting criterion variables than was0191-8869/$ - see front matter Ó 2010 Elsevier Ltd. All rights reserved.doi:10.1016/j.paid.2010.02.015* Corresponding author. Tel.: +1 519 661 3682.E-mail address: [email protected] (P.A. Vernon).Personality and Individual Differences 48 (2010) 884–888Contents lists available at ScienceDirectPersonality and Individual Differencesjournal homepage: www.elsevier.com/locate/paideither form to the nonverbal inventory. This study also reportedrelatively high correlations between the FF-NPQ scales and the cor-responding scales assessed by the verbal inventories.The study by Paunonen (2003) is the only one to date that hascompared the FF-NPQ and the 240-item NEO-PI-R. The first goal ofour study, therefore, is to provide further evidence of convergentvalidity for the new nonverbal Big Five questionnaire. New mea-sures of personality are required to show this type of convergencewith existing measures in order to establish their construct valid-ity. One of the purposes of this study is to verify the correlationsfound in the past between the scales of the FF-NPQ and theNEO-PI-R.Another goal of our study is to investigate the extent to whichindividual differences in the factors assessed by the FF-NPQ areattributable to genetic and/or environmental factors. No previousbehavioral genetic (BG) studies of the FF-NPQ have been con-ducted. However, such studies have been done with verbal Big Fivemeasures, such as the NEO-PI-R. Of course, if the FF-NPQ factorsshow moderate to large correlations with the same factors