Graphology has been tested more directly than many traditional character-reading systems because its central claim is precise and falsifiable: that trained graphologists can predict a person's real, independently measured personality traits or job performance from their handwriting alone. Research from the 1980s onward, including an influential meta-analytic review by Gershon Ben-Shakhar and colleagues, compared graphologists' judgments against genuine criterion measures such as validated personality inventories and supervisor ratings of job performance. The key methodological move was separating content from form: when graphologists were given handwriting samples whose content revealed information about the writer, such as an autobiographical passage, their judgments showed a weak positive correlation with real personality and performance measures, but so did the judgments of psychologists and ordinary laypeople given the same content, working from the content alone.
When graphologists were instead given neutral, copied text that carried no information about the writer, their accuracy dropped to essentially zero, no better than chance. The consistent conclusion across this research is that any apparent validity in graphological assessment tracks the content of what a person chose to write rather than the physical form of their handwriting, which is the one thing graphological theory claims does the actual predictive work. On the strength of this evidence, professional testing bodies including major providers of personnel assessment tools have concluded graphology is not a valid selection method, and its use in hiring, once significant in France and Israel, has declined substantially in recent decades.