Justificación Económica

In order to assess the potential role of mindfulness within the TPB, some way of operationalising mindfulness in the driving context is required. In the past few years, self-report questionnaires to assess mindfulness have begun to appear in the literature (e.g., Baer, Smith, & Allen, 2004; Brown & Ryan, 2003; Lau et al., 2006; Walach, Buchheld, Buttenmuller, Kleinknecht, & Schmidt, 2006). Not surprisingly, given the different conceptualisations of mindfulness reviewed earlier, these

instruments differ in the conceptualisation of mindfulness on which they are based on and the intended usage of the scales. Some of the scales include; the Freiburg Mindfulness Inventory (FMI) (Walach, Buchheld, Buttenmuller, Kleinknecht, & Schmidt, 2006), the Toronto Mindfulness Scale (TMS) (Lau et al., 2006), the Kentucky Inventory of Mindfulness Skills (KIMS) (Baer, Smith, & Allen, 2004) and, the Mindfulness Awareness Attention Scale (MAAS) (Brown & Ryan, 2003). The FMI (Walach, et al., 2006) consists of 30 items for the long version and 14 items for the short version, with both of them comprising a one-dimensional factor. It was developed to assess present-moment observation and openness to negative

experiences. All the items are rated on a 4-point Likert-type scale (rarely to almost always). It has been considered to be a reliable and consistent scale with excellent internal consistency with Cronbach’s alphas of 0.93 (30 items) and 0.86 (14 items). However, the FMI was designed based on the conceptualisation of mindfulness in Buddhist psychology and, hence, has been validated on experience of meditators who have Buddhist meditation knowledge.

Similarly, the TMS (Lau, et al., 2006) is a 13 item instrument and one-dimensional scale with adequate consistency (Cronbach’s alpha of 0.95). This scale measures attainment of a mindful state through meditation exercise and is capable of

discriminating between various levels of meditation of experienced meditators and non-meditators. The TMS is considered to be a useful instrument to investigate the mediating role of mindful awareness in mindfulness-based interventions and for observed patient outcomes. It reflects the components of mindfulness identified by Bishop (2004) in his definition of mindfulness: 1) self-regulation of attention

(individual feeling of being very alert of what occurring at the present moment), and 2) the quality of attention being generated from curiosity, acceptance, and openness to experience. However, the TMS cannot be used outside the mindfulness meditation training.

The Kentucky Inventory of Mindfulness Skills (Baer, et al., 2004) is an instrument with 39 items measuring the general tendency to be mindful in daily life.

Respondents rate each item on a 5-point Likert-type scale ranging from 1 (never or very rarely true) to 5 (almost always or always true). The KIMS divides mindfulness skills into four factors i.e., observe, describe, act with awareness, and accept without judgement. This measurement has been reported to have had an adequate to good internal consistency ranging from 0.87 to 0.91 (Baer, et al., 2004). Although mindfulness scores are often positively associated with constructs related to mental health and better coverage of internal targets of mindfulness, KIMS is grounded by the DBT (Dialectical Behaviour Therapy) conceptualisation of mindfulness. DBT is a form of psychotherapy to treat borderline personality disorder. Thus, KIMS was designed for clinical psychology to assess the general tendency to be mindful in daily life specifically those who involve in DBT.

Finally, Brown and Ryan (2003) developed the Mindfulness Awareness Attention Scale (MAAS) based on their definition of mindfulness. It is a 15 item instrument with a single factor structure. In particular, the MAAS measures the general tendency for an individual to be attentive to, and aware of, the present situation or experiences in daily life. A series of validation studies have been conducted that attest to the scale’s validity and sensitivity to change (Carlson & Brown, 2005; James MacKillop & Emily J. Anderson, 2007). The items have been designed to reflect mindfulness in general terms in daily circumstances. For example,

participants will indicate how often they experience automatic behaviour from 1 (almost always) to 6 (almost never) (i.e., “I do jobs or tasks automatically, without being aware of what I’m doing”), or how often they experience problems in paying attention to the present situation (e.g., “I find it difficult to stay focused on what’s happening at the present moment”). Individuals who score highly on the MAAS are considered to be high on mindfulness, and the scale includes items relevant to

driving (e.g., “I drive places on ‘automatic pilot’ and then wonder why I went there”) (see Appendix A to review the MAAS items).

As mentioned before, although different scales have been developed and validated, all the scales were underpinned by different conceptualisations of mindfulness. The FMI, TMS and KIMS are all based on clinical research and, thus, were measures that focused on mindfulness as relevant to the meditation context. In contrast, the MAAS has been applied mostly in non-clinical research (Giluk, 2009). Compared with the FMI, TMS, and KIMS, the MAAS does not include other dimensions tied to

mindfulness, such as acceptance or trust (Ledesma, et al., 2010). Furthermore, it has been used to validate the Attention Related Driving Errors Scale (ARDES)

(Ledesma, et al., 2010). As such, the MAAS differs from the FMI, TMS, and KIMS, given that it was designed to assess mindful states regardless of meditation or

mindfulness skill training and experience. In relation to driving activities where a driver needs to be attentive to, and aware of, the present situation around them, the MAAS is considered to be the scale most suitable for driver behaviour-related research.

In summary, several instruments have been developed to measure mindfulness. Each instrument differs based on the conceptualisation of mindfulness and the intended

usage of the scale. Accordingly, after examining each of the instruments, the MAAS has been considered as the most suitable instrument for this research.

The next section discusses other factors which may influence drivers’ compliance with the speed limit. In particular, the next section discusses the evidence related to situational factors such as other road users’ behaviour that could influence an individual’s driving behaviour.