Large Language Model Dependency in the UK and Italy: Cross-National Evidence from the LLM-D12 scale

Reliable and culturally comparable instruments are needed to assess psychological dependency on large language models (LLMs) across societal contexts that differ in the extent of LLM use. The present study evaluated whether the LLM-D12, originally developed in the UK, reliably measures Instrumental and Relationship Dependency in Italy, where LLM use is less widespread, and whether scores can be compared directly between the two countries. The LLM-D12 measures Instrumental Dependency, reflecting reliance on LLMs for cognitive support, and Relationship Dependency, reflecting reliance on LLMs for social and emotional support. The sample comprised 1,069 adults from the UK (N = 607; mean age = 28.67 years, SD = 6.18) and Italy (N = 462; mean age = 27.32 years, SD = 5.24). In Italy, confirmatory factor, Mokken, and network analyses supported the two-factor structure, with high internal consistency and clear empirical distinction between the subscales. Strict measurement invariance established that the same constructs were measured in the UK and Italy. UK participants reported substantially higher Instrumental Dependency and higher Relationship Dependency. More frequent use, use while on the move, and text-and-voice interaction were associated with higher dependency, and these associations did not differ by country. Internet addiction was also positively related to both dependency dimensions, with comparable associations in the two samples. Demographic effects were less consistent, with country-specific differences for gender and employment. The findings show that the LLM-D12 retains its two-dimensional structure and measurement comparability in a lower-uptake context and can detect cross-national differences even when dependency levels are relatively low.