Introduction The Brazilian Notifiable Diseases Information System (SINAN) includes eleven work-related diseases and injuries (in nine forms), which communication is mandatory. As a way to evaluate the quality of this database, this study aimed to rate the completeness of information reported by three cities of the São Paulo State from 2007–2016.

Methods Descriptive study as part of ‘Work Accident: from Socio-technical analysis towards the social construction of changes’ supported by the Sao Paulo Research Foundation. Data from the work-related diseases and injuries forms were retrieved from SINAN for Araraquara, Campinas and Piracicaba for the period 2007-2016(16 094 files). Completeness was assessed by the percentage of filled variables by form and city, and it were categorised as: excellent (<5% unfilled), good (≥5,<10% unfilled), regular (≥10,<20% unfilled), poor (≥20,<50% unfilled), and very poor (≥50% unfilled). Analyses were done using STATA 13.1.

Results 669 variables were analysed, one of them is a compulsory field (occupation) and its completeness was very high (≥97%) for all cities. Araraquara had 71.63% variables with excellent completeness, but the occupational dermatosis file had 34.29% variables classified as very poor. Piracicaba showed 56.24% variables classified as excellent, and the occupational dermatosis and cancer files had 41.46% and 55.07% filled very poorly, respectively. Campinas had 40.80% variables filled as excellent, and more than 30% of variables were classified as poor or very poor in all files.

Conclusion There are differences in the completeness among the cities. Routine quality data assessments are crucial to ensure information quality used by health surveillance agents.