Developing strategies and quality control in the Ageing and Brain Working Study in ELSA-Brasil.

OBJECTIVE

To describe all stages of developing strategies and quality control in the Aging and Brain Working Study linked to the Estudo Longitudinal de Saúde do Adulto (ELSA-Brasil - Brazilian Longitudinal Study of Adult Health), a prospective cohort of 15,105 civil servants (aged 35-74) followed up since 2008.

METHODS

Based on the sample of participants alive at the beginning of the sample selection in September 2022 (n = 4,566) from ELSA-Brasil (Centro Investigação São Paulo), a representative sample of 2,165 individuals was calculated according to the following criteria and divided into two subsamples: (1) Sample of participants < 70 years old in Wave 3 (2017-2019) randomized according to cognitive trajectory from Wave 1 to 3, n = 1,670; (2) SuperAgers case-control sample, individuals aged ≥ 70 years in Wave 3, based on episodic memory in Wave 3, n = 495 participants (171 cases, 324 controls). The processes implemented to ensure quality control of information prior to data collection were selection of data collection instruments, training and certification of teams, preparation of a manual of definitions and standardized operating procedures, pilot studies, data collection logistics, harmonization of imaging protocols, and creation of an anti-noise device. Given the scope of the study, its multicenter nature, and the diversity of measures involved, this project required the implementation of effective quality assurance and control protocols, ensuring standardization, methodological consistency, and data integrity at all stages.

RESULTS

After implementing the quality assurance and control processes, the final stages related to clinical and imaging data collection, management, and continuous monitoring of field activities were conducted, with weekly reports and statistical monitoring of the sample.

CONCLUSIONS

The adoption of systematic stages of development and quality control was fundamental to ensure the production and reliability of information from brain neuroimaging studies.