Personality refers to “psychological qualities that contribute to an individual’s enduring and distinctive pattern of feeling, thinking, and behaving” (Cervone and Pervin, 2013, p. 8), and thus to “individual differences, or the dimensions along which people differ from each other” (Barenbaum and Winter, 2008, p. 7). The first psychological literature review of personality emerged in 1921 (Allport, 1921), and personality has since been a fundamental concept in psychology. Research has demonstrated that personality traits predict a variety of outcomes, such as health, longevity (Ozer and Benet-Martinez, 2006; Roberts et al., 2007), job performance and satisfaction (Judge and Bono, 2001), consumption of psychoactive substances (Paunonen and Ashton, 2001), political participation (Mondak and Halperin, 2008), economic and social policy attitudes (Gerber et al., 2010), wage and occupational self-efficacy (Sadeghi et al., 2022), and traffic behavior (Ulleberg and Rundmo, 2003). Personality is characterized by a cross-disciplinary applicability, by not solely being of interest within psychology, but in all research areas that on some level deal with human factors (Roberts et al., 2007), such as sociology, education and business. In research studies, personality traits may be utilized as predictors or outcomes (the study variables of primary interest), as mediators or moderators, or simply as important control variables when studying relationships between other constructs.

The five-factor model (FFM) of personality, also known as the Big Five personality model, is the leading framework for understanding individual differences (McCrae and Costa, 2008; Sprecht et al., 2014). According to the FFM, personality is composed of five broad domains: extraversion (E, being sociable and active), agreeableness (A, being soft-hearted and trusting), conscientiousness (C, being organized and reliable), emotional stability (ES¹, being calm and relaxed), and openness (O, being curious and creative) (Costa and McCrae, 1992). The FFM has been shown to be quite consistent across cultures (McCrae et al., 1998).

Several instruments have been developed to measure the five domains of the FFM, of which the 240-item NEO Personality Inventory-Revised (NEO-PI-R, Costa and McCrae, 1992), the 60-item NEO Five-Factor Inventory (NEO-FFI, Costa and McCrae, 1992), and the 44-item Big Five Inventory (BFI, John and Srivastava, 1999) are the most prominent. Due to their number of items, these FFM instruments are impractical to administer in studies that do not aim to answer research questions primarily related to personality (DeBell et al., 2022). The most extensive tool (the NEO-PI-R) takes about 45 min to complete (Gosling et al., 2003). Even the NEO-FFI and the BFI, which take 15 and 5 min to complete, respectively (John and Srivastava, 1999), may be too comprehensive in many instances. Long surveys may reduce participation rates (Rolstad et al., 2011), due to respondents being bored or fatigued (Credé et al., 2012), which may result in data quality decrements. This represents a particular concern for longitudinal studies that require repeated measurements (Herzberg and Brähler, 2006).

The need for brief FFM instruments is evident, particularly in instances when researchers want to study personality as just one out of several other constructs, or utilize personality traits as control variables. In 2003, Samuel Gosling and coworkers introduced the Ten-Item Personality Inventory (TIPI) as a brief instrument to assess the FFM personality dimensions (Gosling et al., 2003). The TIPI consists of 10 items, with five two-item subscales that correspond to the FFM dimensions. The initial evaluation of the TIPI (Gosling et al., 2003) found that it was an appropriate alternative to more extensive FFM instruments, with acceptable validity, reliability, and external correlations. For several reasons, the TIPI stands out as appealing to researchers: It is freely available (Storme et al., 2016), and it takes approximately just 1 min to complete (Nunes et al., 2018), thereby extending the scope of studies in which FFM personality dimensions can be taken into account (Gosling et al., 2003). The evident appeal of the TIPI is reflected in its widespread use, as the initial validation article (Gosling et al., 2003) has been cited more than 9,500 times in the research literature. Moreover, according to the official TIPI website (Gosling, n.d.), the original instrument has been translated into at least 26 different languages for worldwide utilization.

However, as noted by Ehrhart et al. (2009), the interest in utilizing the TIPI quickly outpaced the efforts spent on investigating the instrument’s psychometric properties. Psychometric properties refer to the degree of validity and reliability associated with a measurement instrument (Asunta et al., 2019). Validity represents the degree to which an instrument measures the construct(s) it purports to measure (Mokkink et al., 2010, p. 743). Structural and convergent validity, both elements of construct validity, are of particular importance. Scores on the instrument should represent an adequate reflection of the dimensionality of the construct to be measured (structural validity), and scores on the instrument should correlate with scores on other instruments designed to measure the same construct (convergent validity) (Cunningham et al., 2001; Mokkink et al., 2010). The concept of reliability captures the extent to which an instrument is free from measurement error, which is often expressed in terms of the degree of interrelatedness of the items (internal consistency) and the instrument’s ability to generate similar results when repeatedly administered to the same respondents under the same conditions (test–retest reliability) (Mokkink et al., 2010; Noble et al., 2021).

Testing of psychometric properties such as internal consistency and structural validity rests on an assumption of the measure being reflective rather than formative. Reflective measures presume that the test items are caused by a common latent variable, while formative measures postulate that the construct being measured represents a function of the items, rather than the other way around (Markus and Borsboom, 2013). For instance, in the case of the E subscale in the TIPI, one could argue that being sociable and active are behaviors caused by high levels of extraversion (reflective approach), or alternatively that high extraversion is a function of being sociable and active (formative approach). Being developed on the basis of reflective techniques (such as factor analysis), the FFM is generally measured by means of reflective approaches (McCrae and John, 1992).

Comprehensive instruments tend to have better psychometric properties than shorter instruments (Gosling et al., 2003). For instance, short scales generally suffer from not being able to suppress random error through aggregation of items (Herzberg and Brähler, 2006), and from being characterized by content deficiencies (Smith et al., 2000). However, some studies indicate that psychometric shortcomings associated with brief instruments may not be severe enough to discourage the use of short scales in research altogether (Credé et al., 2012). In practice, researchers have to make a trade-off and strike an appropriate balance between maximizing psychometric properties on the one hand, and minimizing administration time and survey length on the other (Furnham, 2008). As noted by Gosling et al. (2003, p. 505), “researchers may be faced with a stark choice of using an extremely brief instrument or using no instrument at all.”

Authors have emphasized the need for further attention to psychometric properties of the TIPI (Ehrhart et al., 2009), and for secondary research efforts to provide an overview of different versions of the TIPI and their psychometric properties (Thørrisen et al., 2021). The aim of the current scoping review was to generate an overview of different versions of the TIPI, and their psychometric properties in terms of two aspects of validity (convergent and structural) and two aspects of reliability (internal consistency and test–retest reliability).

Database searches identified 581 studies (PsycINFO: n = 116; PubPsych: n = 167; Medline: n = 134; Web of Science: n = 164). Of these, 164 duplicates were removed and 417 unique studies were screened on a title/abstract level. A total of 385 studies were excluded due to not fulfilling the eligibility criteria, and the remaining 32 studies were subjected to full-text examination. At this stage, another 11 studies were excluded as a result of not having exploration of psychometric properties of the TIPI as a study aim (n = 7), due to not being published in English (n = 3), or not being published as a peer-reviewed research article (n = 1). Hence, 21 studies from database searches were included in the scoping review. Manual searches on the TIPI website and in reference lists resulted in an additional eight studies being included (website: n = 3; reference lists: n = 5). In total, 29 studies were included in the scoping review. The study selection process is illustrated in Figure 1.

The 29 included studies were based on a total of 27,427 participants from 20 countries (Bangladesh, Brazil, China, Croatia, France, Georgia, Germany, Indonesia, Iran, Italy, Japan, Netherlands, Norway, Poland, Portugal, South Africa, Spain, Turkey, the United Kingdom, and the United States), published from 2003 (Gosling et al., 2003) to 2022 (DeBell et al., 2022; Shi et al., 2022). Sample sizes ranged from N = 100 (Furnham, 2008) to N = 5,009 (Thørrisen et al., 2021). Characteristics of the included studies are presented in Table 2.

The aim of this scoping review was to generate an overview of different versions of the TIPI, and their psychometric properties in terms of two aspects of validity (convergent and structural) and two aspects of reliability (internal consistency and test–retest reliability). A total of 27 TIPI versions were identified in 29 studies, covering 18 different languages. Across versions, and held up against conventional standards of psychometric properties, the TIPI has demonstrated acceptable test–retest reliability, mixed results for convergent and structural validity, and inappropriate internal consistency.

The TIPI is a very brief instrument that intends to capture the breadth of the FFM personality dimensions by means of five subscales, each consisting of two items. It has been emphasized that such an instrument cannot be expected to excel in terms of psychometric properties such as structural validity and internal consistency (Gosling et al., 2003). As noted by Chiorri et al. (2015, p. 110), improved structural validity and internal consistency could quite easily have been achieved by including only “items with a very high correlation (e.g., r > 0.70), which, given their unavoidable redundancy, would have undermined content coverage.” Not surprisingly, of the 23 TIPI versions tested for internal consistency, only one version demonstrated acceptable consistency on all five FFM dimensions. It is noteworthy that the vast majority of tests of internal consistency in the included studies utilized Cronbach’s α. Estimates of α are strongly influenced by the number of items in each subscale (Kline, 2000), which is why authors have recommended application of S-B coefficients rather than α coefficients when exploring internal consistency of instruments with brief subscales (e.g., Eisinga et al., 2013). On the other hand, the four TIPI versions actually explored with S-B coefficients did not stand out as substantially more or less internally consistent than those versions investigated by means of alpha (α) and Pearson (r) coefficients.

Although acceptable structural validity may not be expected for brief instruments aiming to maximize content coverage, five-factor structures theoretically corresponding with the FFM were identified for 8 of the 19 TIPI versions that were tested for structural validity. As such, some evidence of structural validity of the TIPI does exist, even though results were quite mixed across the different versions.

Given the TIPI’s brevity (five two-item subscales) and purpose (maximization of content coverage across the FFM dimensions), the developers of the instrument emphasized the relevance and importance of convergent validity and test–retest reliability when evaluating psychometric properties of the instrument (Gosling, n.d.; Gosling et al., 2003). All 17 versions that were tested for test–retest reliability displayed acceptable temporal stability on all five FFM dimensions. Hence, this scoping review indicates evidence of acceptable test–retest reliability of the TIPI. However, results for convergent validity were somewhat mixed. Overall, the TIPI displayed strongest convergence with the BFI, with 6 out of 9 tested versions indicating acceptable convergence on all five subscales. Only one version converged satisfactory with the NEO-PI-R on all five dimensions, and none of the tested TIPI versions displayed acceptable convergent validity with all five NEO-FFI dimensions. Still, mean convergences for all tested TIPI versions across all five dimensions reached acceptable levels of correlation (r ≥ 0.50) with the BFI, the NEO-FFI, and the NEO-PI-R dimensions.

Given that the TIPI is generally not expected to reach conventional standards of internal consistency and structural validity, some authors have raised the issue of whether the TIPI should be conceptualized as a formative rather than a reflective measure (Myszkowski et al., 2019). The TIPI, in line with other FFM instruments, is generally conceived as a reflective measure, i.e., as a measure consisting of items believed to be correlated and to constitute effects of common latent factors (Markus and Borsboom, 2013). Alternatively, one may conceptualize the TIPI items as samples of particular behaviors rather than correlated effects of common factors, i.e., as a formative measure (Markus and Borsboom, 2013). In an interesting study, Myszkowski et al. (2019) subjected the TIPI to formative measurement evaluation, and concluded that such an approach could be more appropriate for the TIPI than a traditional reflective approach. On the other hand, being developed on the basis of reflective techniques such as exploratory factor analysis (McCrae and John, 1992), one may argue that the FFM is reflective by nature, although the nature of the constructs being measured does not necessarily dictate the approach for instrument development and evaluation (Myszkowski et al., 2019). Further exploration of the TIPI as a potentially formative measurement instrument constitutes a venue for future research.

It should be noted that psychometric shortcomings and variations across different versions of the TIPI may, at least partly, be traced to issues of language and translation procedures. Adequate translation of measurement instruments requires taking psychological, linguistic and cultural considerations into account, preferably within the frame of translation-backtranslation procedures (van de Vijver and Hambleton, 1996; van de Vijver and Tanzer, 2004). The included studies and the TIPI website generally provided scarce information about the translation procedures utilized when the non-English versions of the TIPI were developed. The overall pattern of results from psychometric testing did not differ considerably between English and non-English versions of the TIPI, indicating that item bias due to suboptimal translations may not have played an important role in explaining the psychometric shortcomings identified in this scoping review. However, in some of the included studies, poor item translation necessitated reformulation of items, resulting in two or more versions in the same language. For instance, when exploring the first Dutch version of the TIPI (DUT-1), Hofmans et al. (2008) reported having to rephrase five of the items, resulting in a second Dutch version (DUT-2) that demonstrated more adequate psychometric properties.

In the original validation of the TIPI, the instrument’s developers (Gosling et al., 2003) stated that the TIPI demonstrated adequate psychometric properties and that it stood out as a reasonable proxy for more comprehensive FFM instruments in instances where brief measures are necessary to minimize participants’ response burden. The results of our current scoping review largely corroborates the developers’ initial conclusions. The TIPI stands out as a serviceable measure when researchers want to study personality as one among several constructs, and in instances where it may be appropriate to include individual differences simply as covariates or control variables. Consequently, the TIPI carries the benefit of making personality measurement available for a broad scope of studies, both within and beyond the field of psychology. However, use of the TIPI should be discouraged in studies that primarily aim to explore personality, due to the instrument’s psychometric shortcomings (compared with more comprehensive FFM instruments), and due to the TIPI not being able to measure and distinguish between narrow facet-level constructs that underlie the five broad dimensions in the FFM.

Although this scoping review provides some evidence in favor of the TIPI, it must be noted that psychometric properties and extent of exploration of such properties, varied considerably between the 27 identified versions of the instrument. For some versions, only two psychometric domains were tested. For others, psychometric properties were tested in a single study only. Moreover, more than half of the studies included in this scoping review (15 of 29) were solely based on student samples, while general population samples were included in only 7 out of the 29 studies. Therefore, further psychometric research on the TIPI is warranted.

As the first secondary research effort focusing on the TIPI, this scoping review explored 27 versions of the instrument across 29 studies, covering 18 different languages. Being a brief instrument, the TIPI is indeed characterized by certain psychometric shortcomings. However, this scoping review supports that the TIPI may represent a feasible compromise in instances where it is necessary to strike a balance between maximizing psychometric properties and minimizing survey length. In particular, the TIPI stands out as a serviceable option when researchers want to study personality as one among several constructs, and in instances where it is appropriate to include individual differences simply as covariates or control variables.

This study was designed by MT and TS. MT analyzed the data and drafted the manuscript. Study selection and data extraction were performed by MT and TS. TS provided scientific input to the different drafts and provided data interpretation. MT and TS made critical revisions and provided intellectual content to the manuscript, approved the final version to be published, and agreed to be accountable for all aspects of this work. All authors contributed to the article and approved the submitted version.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

The Supplementary material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fpsyg.2023.1202953/full#supplementary-material