Critical Review of Psychometric Properties of Projective Techniques: The Case of the Lüscher Color Test and the Szondi Test

Abstract

The article presents a critical analysis of the psychometric properties of two widely used projective techniques: the Luscher Color Test and the Szondi Test. The study aimed to synthesize data on their validity, reliability, and theoretical foundations through a review of scientific sources (Scopus, PubMed, Google Scholar). Results indicate that the Luscher Test demonstrates low convergent validity (no correlations with MMPI, IPAT), unstable test-retest reliability (mean r ≈ 0.33–0.37), and lack of measurement invariance due to cultural, gender, and age influences on color preferences. Effects of social desirability and the Barnum effect were identified. The Szondi Test exhibits significant stimulus validity issues (photo selection driven by visual characteristics/social stereotypes), unconfirmed criterion validity (minimal correlation with PCL-R), undefined factor structure, and low test-retest reliability. Its theoretical basis (genotropism) contradicts modern classifications of mental disorders (DSM-5-TR, ICD-11). Both instruments, alongside other projective techniques (e.g., Koch’s Tree Test), are labeled by researchers as "probably" or "certainly discredited" due to insufficient evidence of psychometric soundness. Their use risks misdiagnosis, erroneous expert conclusions (including in legal settings), and undermines psychology’s scientific credibility. The conclusion emphasizes that developers bear responsibility for demonstrating scientific validity, and only tools with empirically confirmed psychometric properties are suitable for professional application.