Does Passion Precede Practice? A Five-Wave Longitudinal Validation of the Passion Scale in Professional Football Referees

This preprint reports a five-wave longitudinal psychometric validation of the Passion Scale (Vallerand et al., 2003) in a near-census sample of professional football referees (N = 486–619; Federação Paulista de Futebol, Brazil; 2010–2016). BACKGROUND: Despite growing application of the Dualistic Model of Passion (DMP) to sport officiating, no study has examined the psychometric properties of the Passion Scale in professional football referees across longitudinal waves, nor tested whether harmonious passion (HP) precedes or results from professional practice. METHODS: Census-design longitudinal study across five waves (T1–T5, 2010–2016) with an additional pre-certification cohort (EAFI; N = 260, T6, zero professional experience). Confirmatory factor analysis (CFA), measurement invariance testing, latent growth modelling (LGM), and exploratory factor analysis (EFA) of 22 antecedent items were conducted. The HP−OP Balance Index (IP = HP − OP) is introduced as a longitudinal composite measure. KEY FINDINGS:- Full scalar measurement invariance confirmed across T1–T5 (ΔCFI ≤ .007)- HP grows monotonically T1→T5 (d = 0.53); OP oscillates with competitive calendar- OP shows greater within-person variability than HP (d = 0.48; 66.1% of census)- EAFI pre-certification students show HP statistically equivalent to T5 professionals (d = 0.01, p = .953) and higher than T1 professionals (d = 0.50, p = .003)- HP uncorrelated with years of experience (r = −.037, ns)- EFA of 22 antecedent items yields 3 factors matching DMP internalization predictions- IP Balance Index outperforms individual HP and OP subscales as longitudinal predictor across all outcome domains CONCLUSIONS: The Passion Scale demonstrates strong psychometric properties in professional football referees. The pre-certification evidence supports the DMP proposition that harmonious passion precedes and operates independently of professional practice — not the reverse. The HP−OP Balance Index is proposed as a parsimonious longitudinal measure for future DMP research.