# Validation of the Player Personality and Dynamics Scale
## 2 Materials and Methods
### Instruments  
To identify different player personalities and dynamics, an ad hoc questionnaire was developed specifically for this research project. The complete instrument, together with the anonymized response data, has been deposited in Zenodo [11] to ensure transparency and facilitate replication. The instrument comprised a set of questions covering sociodemographic data, lifestyle-related aspects, information on the participant's relationship with video games, and the Player Personality and Dynamics Scale:  
**Sociodemographic data:** Given that the study focused on young individuals and students, the sociodemographic section emphasized educational background and household structure. Variables included gender, age, level of education, place of residence (country and autonomous city or region, if in Spain), employment status, academic field, average academic performance, class attendance frequency, academic repetition, living arrangements, and monthly family income.  
**Lifestyle data:** In light of existing stereotypes that associate gamers with unhealthy lifestyles, this section aimed to provide a broader view of participants' habits. It included items on dietary practices, body mass index (BMI) as a reference for general health, and substance use (alcohol, tobacco, and other substances).  
**Gaming habits:** Closely aligned with the scale's focus, this section explored both the quantitative and qualitative aspects of players' relationship with video games. Variables included: time spent gaming (in hours per session), the year participants started playing video games, engagement in eSports, and self-assessed skill level.  
**Scale:** The Player Personality and Dynamics Scale initially consisted of 40 items rated on a 6-point Likert scale measuring the frequency of specific behaviors described in each item. The first three response options reflected low or moderately low frequency (1 = Never, 2 = Almost never, 3 = Occasionally), while the next three indicated medium to high frequency (4 = Sometimes, 5 = Often, 6 = Always). The decision to adopt a six-point scale was based on findings by [PERSON] et al. [12], who recommended between four and seven response options for optimal reliability and validity. Using six points--rather than the more common five--helped minimize the tendency for respondents to select a neutral midpoint (typically option 3). Given that some items described undesirable or socially sensitive behaviors, this format reduced the likelihood of participants defaulting to neutrality to avoid social desirability bias.  
To refine the original 40-item instrument, we applied statistical and theoretical criteria iteratively. In each round of confirmatory factor analysis performed using Mplus 8 (Muthen & Muthen, Los Angeles, CA, USA) [13], we removed items with factor loadings below 0.40 or with substantial cross-loadings on two or more factors. Additionally, any item whose content lacked narrative coherence with the other indicators of its factor, despite slightly exceeding the loading threshold, was discarded to ensure conceptual consistency within each dimension. This process yielded the final 21-item scale.  
The inclusion of sociodemographic, lifestyle, and gaming habit variables was also intended to allow for future research exploring mean differences between these criterion variables and the factors extracted from the Player Personality and Dynamics Scale.