Objectives The aim of this study was to evaluate the dimensional structure of the SRQ-20 in different occupational groups. It’s a validation study that involved four sectional drawing surveys.

Method Individual analysis of the databases has been conducted by using the method of principal components. The latent class analysis has been used in the factor analysis of tetrachoric correlations in order to assess the dimensionality of the instrument, aiming to tailor the assessment method to the distribution of variable (categorical). The Vuong-Lo-Mendell-Rubin test adjusted Lo Mendell Rubin (LRT Test), the parametric bootstrap verisimilitude ratio test has been used to review the adequacy of the number of classes extracted in the recipiency of the CMD. The reliability of the latent classes has been evaluated by Latent Class Reliability Coefficient (LCRC).

Results The factor analysis of tetrachoric correlations allowed the assessment of the dimensions of the SRQ-20 and the comparison between different categories of workers. As a complement, the latent class analysis permitted the interpretation of subgroups for expressions of common mental disorders in the occupational sphere, providing in-depth research.

Conclusions The study combined two methods of analysis for assessing the dimensional structure of the SRQ 20 among workers. The factor analysis of tetrachoric correlations enabled us to verify the dimensional stability of the instrument, since the number of extracted factors and dimensions represented maintained similarities in the groups assessed. The study points to the use of measures of SRQ 20 as valid for screening TMC occupational groups.