This investigation consisted of an observational study, in which data from 250 records of psychological evaluations for carrying firearms performed with police officers from a police organization in the southern region of Brazil were examined. These evaluations were carried out from 2015 to 2021. The sample included both active and retired police officers. The police officers underwent psychological evaluation with the aim of restoring the right to carry firearms, which had been suspended due to internal regulations of the organization. All police officers were evaluated by police psychologists belonging to the organization’s permanent staff. The dataset used for this research was provided by the Police Organization after approval by the Human Research Ethics Committee of the Federal University of Santa Catarina, through opinion number 5,397,946.

Within the scope of the internal policies of the institution where the study was conducted, it is stipulated that, in the event of absence from work upon a medical recommendation reported on a health certificate indicating a diagnosis of mental disorder, the right to carry a firearm is compulsorily suspended. In order to reactivate the right to carry a firearm, a psychological evaluation indicating psychological aptitude for the use of firearms is required. Likewise, upon retirement, police officers lose the right to carry a firearm due to the change in employment relationship and, in order to regain that right, police officers are required to undergo a psychological evaluation conducted by psychologists belonging to the institution. It is important to highlight that the psychological evaluations of the police officers followed the guidelines of the Federal Council of Psychology and the Normative Instruction No. 78 of the Federal Police, with regard to the technical, ethical and methodological procedures of the psychological evaluation.

The data source provided by the organization contained demographic, occupational, and clinical information, as well as data on psychological instrument scores. Demographic variables included gender, age, and education. Occupational variables included data on position held, type of employment relationship with the organization, and length of police service. Clinical variables were characterized by the presence or absence of mental disorder and classification according to the International Statistical Classification of Diseases and Related Health Problems – ICD-10 (World Health Organization, 2003), i.e., the medical diagnosis reported on the health certificate. Psychological variables referred to the scores on cognitive screening instruments related to memory, logical reasoning, and general attention (mean of the scores for concentrated, divided, and alternating attention); and quantitative personality indicators from the Palographic test.

The psychological variables were measured using tests with established psychometric validity and reliability, all approved by the Brazilian Psychological Test Assessment System at the time of their application. The tests were applied individually, in the presence of the psychologist, following the application standards contained in the test manual. To assess attention, the following tests were used: Psychological Battery for Attention Assessment (Rueda, 2010), Concentrated Attention Test – TEACO – FF (Rueda, 2009), Alternating Attention Test – TEALT (Rueda, 2010), Divided Attention Test – TEADI (Rueda, 2010. To assess memory, the following tests were used: Recognition Memory Test – TEM-R (Rueda et al., 2016), Pictorial Memory Test – TEPIC-M (Rueda & Sisto, 2007). The nonverbal intelligence test – R-1 (Alves, 2012) was used to assess intelligence. The following tests were used to assess personality characteristics: Palographic Test in personality assessment (Alves & Esteves, 2019), and the Pfister test. The results obtained in the Pfister test were not reviewed in the present study.

The data were analyzed using statistical procedures. Initially, descriptive statistics were performed to characterize the sample. Subsequently, inferential statistics were performed to examine the validity of the study hypotheses. The normality of all continuous variables in the study was tested using the Kolmogorov-Smirnov and Shapiro-Wilk tests. Among the continuous variables, only general attention presented a normal distribution. Thus, statistical comparisons between general attention and the categorical variables were performed using parametric tests: Student’s t-test, analysis of variance (One-way ANOVA) and Tukey’s post hoc test. Memory and reasoning were assessed using nonparametric tests: Mann-Whitney U test and Kruskal-Wallis test, since they did not meet the assumption of normality. Spearman’s correlation coefficient was used to assess associations between quantitative variables, with effect sizes interpreted according to Cohen’s criteria. Data organization, processing, and review were carried out using Excel and IBM®SPSS® (version 21). A significance level of p < 0.05 was adopted for all analyses.

Demographic, occupational and clinical characteristics are presented in Table 1.

Among the 250 psychological assessment records reviewed, the predominant demographic profile was as follows: male participants (81.6%), with an average 50 years of age (SD = 12.7), and higher education (75.0%). The age range spanned from 24 to 78 years, with the most frequent age group being 52–65 years (42.0%). Most participants (75.0%) had higher education, and the sample was nearly equally divided between active and retired police officers (51.0% and 49.0%, respectively). The majority of participants (40.0%) had between 25 and 36 years of police service, that is, they were close to retirement. The second most frequent age range was situated in the first years of the career, between 1 and 12 years of service (33.0%). The attestation of mental disorder was classified as yes (35.6%) and no (64.4%), considering the clinical condition documentary record.

Table 2 shows the distribution of mental disorders according to length of service, age group and sex.

Mental disorders were more frequent among police officers who were at the beginning of their careers, i.e., between 1 and 12 years of service (53.9%). The age group with the highest frequency of mental disorders was 38 to 51 years (56.1%), followed by the age group 24 to 37 (26.9%), with the average age being 43 years. (Table 2)

To test hypothesis 1, correlations between age and the scores obtained on the cognitive function screening instruments were examined (see Table 3). Significant negative correlations were found between age and all cognitive variables tested. Effect sizes were moderate for all of them: age and memory (r = -0.546; p < 0.01), age and reasoning (r = -0.523; p < 0.01), and age and general attention (r = -0.423; p < 0.01).

Additional assessments revealed significant differences in cognitive scores between younger officers (24–51 years old) and older officers (52–79 years old), with younger officers performing better on memory and general attention scores. Within the age subgroups, significant differences were found only for reasoning between the 24–37 and 38–51 year groups. The results suggest that cognitive decline varies by age group, which can be seen in detail in Figure 1.

These findings confirmed hypothesis 1 of the study: There is a significant difference in the performance of cognitive tests according to age. Cognitive functions declined as the age of the police officers increased. This age-related decline in cognitive performance, commonly observed in other populations (Borda et al., 2019; Nascimento et al., 2015; Rodrigues et al., 2008), has significant implications for firearm-related work, emphasizing the need for targeted preventive measures for older officers.

Cognitive test scores were compared based on two education levels: high school and higher education. Due to career policy changes requiring higher education for entry into the police force after 2009, participants with only high school education were older and had longer service or were retired.

As shown in Table 5, significant differences between the two groups for the three cognitive variables. As expected, police officers with high school education obtained lower results in memory, reasoning and general attention, compared to the group of police officers with higher education. These results converge with those found in relation to age, since the police officers belonging to the high school education group are also the oldest.

Table 6 compared the scores of the cognitive screening instruments between the types of employment: active and retired.

Significant differences were found for memory, reasoning, and general attention, with active officers demonstrating superior cognitive performance compared to retired officers.

Comparisons between groups with and without mental disorders according to the scores of the cognitive screening instruments are presented in Table 7. Contrary to expectations, officers with a mental disorder diagnosis scored higher in memory, reasoning, and general attention.

A possible explanation for this result may be associated with the fact that most police officers diagnosed with mental disorders (83.15%) belong to the youngest group in the sample, specifically in the age groups of 24 to 37 years and 38 to 51 years, who are also the most educated. As illustrated in Figure 1, police officers between 24 and 51 years demonstrated significantly better cognitive performance compared to those in the age groups of 52 to 65 years and 66 to 79 years.

The statistical analyses refuted hypothesis 2: Police officers diagnosed with mental disorder have lower performance in cognitive tests than those who do not present such a diagnosis. Instead, the findings suggest that in this sample, a mental disorder diagnosis did not negatively impact cognitive functions, diverging from trends reported in the literature.

The results highlight the importance of age, education, and employment status in understanding cognitive performance among police officers. The findings underscore the need for regular cognitive evaluations, particularly for older and retired officers, to address potential implications for firearm-related work.