Health disparities
Wednesday 8 October 2025, 13.30 – 14.30 Flash
Chairs: Karen Oude Hengel, Joanne Kim
Adaptation and content validity of a battery of questionnaires for identifying occupational conditions among Chilean artisanal and small-scale miners
Natalia Lucero (presenter)
María Teresa Muñoz-Quezada, Cristobal Jeldrés, Gabriel Peña, Guillermo Farmer, Rodrigo Villegas, Karla Yohannessen, Benjamín Castillo, Fabián Araya, Rolando Villasau, Verónica Iglesias
Abstract
Objective: This study aimed to adapt and validate the content of a set of questionnaires developed to identify occupational conditions affecting artisanal and small-scale miners in Chile. Given the precarious and informal nature of this sector, existing assessment tools are often unsuitable. The goal was to design appropriate instruments to support occupational health monitoring and inform inclusive public health interventions. Material and Methods: A cross-sectional descriptive study was conducted in three phases. First, we reviewed national and international occupational health protocols related to mining. Second, we developed eight questionnaires covering key occupational conditions such as exposure to silica, ultraviolet radiation, noise, diesel exhaust, pesticides, biological hazards, and musculoskeletal strain. Third, a formal expert judgment process was conducted with 25 professionals from occupational health, epidemiology, psychometrics, statistics, and mining, who evaluated 165 items based on clarity, relevance, sufficiency, and coherence. Each criterion was rated on a four-point Likert scale. We calculated item-level and overall content validity indices and applied Aiken’s method, with a threshold of 0.80 for acceptance. Results: Overall, 87% of items met or exceeded the threshold across all four criteria. The average Aiken’s values ranged from 0.77 to 0.98. The diesel exposure module achieved the highest average content validity scores (all criteria >0.90), while the employment conditions module scored lowest in clarity (0.77), prompting revision of 26% of its items. A total of 25 items (15%) were removed and 65 items (39%) were modified. A new chemical exposure questionnaire was created by integrating items from pesticide and diesel modules. Expert feedback ensured contextual and linguistic adequacy, particularly for low-literacy populations. Conclusion: This battery is the first validated tool specifically designed for Chilean artisanal mining settings. It is intended to support participatory occupational health diagnosis. Field testing is planned to confirm reliability.
Serum organochlorine insecticide concentrations and risk of aggressive prostate cancer
Stella Koutros (presenter)
Deborah Tadesse, Lauren Hurwitz , Richard B Biritwum, Yao Tettey, Andrew Adjei, Evelyn Tay, Andreas Sjodin, Richard Jones, Mark Davis, Florence Menegaux, Mustapha Abubakar, Evans A Akpakli, Kenneth Klufio, James E Mensah, Sonja I Berndt
Abstract
Prostate cancer is one of the leading causes of cancer morbidity and mortality among men worldwide, with heightened rates in Africa and the Caribbean. Although few risk factors have been identified, studies have shown positive associations with exposure to persistent organochlorine pesticides (OCPs) and aggressive prostate cancer. Few studies have studied OCPs in Africa despite continued exposure and the high burden of prostate cancer. Here we described predictors of serum levels of OCPs in 300 prostate cancer cases (within 1-yr of diagnosis) and 300 population-based controls enrolled in the great Accra region of Ghana (2004-2012). Serum concentrations of three DDT (dichlorodiphenyltrichloroethane) metabolites were measured: pp’-DDE, pp’-DDT, op’-DDT. Chi-Square tests were used to examine the relationship between DDT and demographic/lifestyle factors in controls. Levels were reported in cancer cases by clinical factors, including high-grade (Gleason≥8) and advanced stage (T3 or T4) disease. Among 300 controls, the geometric means (and percent detected) of pp’-DDE, pp’-DDT, and op’-DDT were at 737.6 ng/g-lipid (99.7% detect), 48.4 ng/g-lipid (95.6% detect), and 16.7 ng/g-lipid (45.3% detect), respectively. Increasing BMI was associated with higher serum levels of pp’-DDE and pp’-DDT (chi-square p-value=0.064 and 0.002, respectively). In cases, higher mean levels of pp’-DDE were observed in men with high-grade compared to low-grade disease (1109.3 ng/g-lipid vs. 760.4 ng/g-lipid, p-value=0.038) and in men with advanced disease (1139.2 ng/g-lipid vs. 838.7 ng/g-lipid, p=value=0.028). Measurable levels of DDT were abundant in serum samples in men from Ghana (pp’-DDE=737.6 ng/g-lipid vs. 262 ng/g-lipid and nondetectable op’-DDT in Black men in the U.S.), suggesting ongoing exposure. Consistent with reports that DDT is highly fat soluble, higher BMI was associated with higher serum concentrations. Serum levels of pp’-DDE were higher for those with aggressive prostate cancer, offering evidence of a plausible link between exposure and aggressive prostate cancer risk in Africa.
Neurodivergent, other disabled and non-disabled working age people: A latent class analysis of patterns of employment and mental health
Evangelia Demou (presenter)
Martina Lippi, Kathleen Riach
Abstract
Objective: This study aimed to explore and compare patterns of employment and mental health between neurodivergent, other disabled and non-disabled people of working-age. While work is a recognised social determinant of health, its effects can be amplified for disabled people of working age, and particularly neurodivergent people. Yet, within the sparse number of studies focussing on neurodivergent people, confirmatory type analyses mainly restrict their focus to loneliness and isolation as mental health indicators for this cohort. Material and Methods: We used UK Biobank data of all working age (40-64 years old, n=289,295) adults at baseline. We divided participants in three categories – neurodivergent, other disabled and non-disabled- and performed exploratory latent class analysis to identify patterns of employment and mental health. Class prevalences were compared between groups, after adjusting for age, gender, educational qualification and area population density. We complemented the analysis with identifying mean age at diagnosis for neurodivergent people and regressing it to investigate their likelihood to be in employment. Results: Latent class analysis resulted in a five-class model ranging from employed with low mental health issues to unemployed with high mental health issues. Compared to the other groups, neurodivergent were mostly prevalent in the unemployed and high mental health issues class. Findings demonstrated a positive impact of higher educational qualification and living in urban areas on employment and mental health. The high average age of diagnosis (54.67± 9.57 years), exacerbated low employment and mental health conditions. Conclusion: Our findings demonstrate that neurodivergent are disadvantaged in terms of employment and mental health issues. This is exacerbated by challenges associated with receiving a late diagnosis and late support during their educational path. The results are highly relevant for current policy debates and highlight the need for urgent interventions targeting health, employment and education policies and practices for this group.
The social division of work injuries through occupation and industry: A synthetic measure based on massive French administrative data
Emilie Counil (presenter)
Grisela Prenga, Néné Traore
Abstract
Objective: Work-related injuries are a major social and public health problem, which can lead to a considerable reduction in healthy life years and carry a great potential for prevention. Our aim was to measure occupational inequalities in work-injury rates in France, using the largest source of information currently available, and a method recently developed by others to study occupational disparities in fatal work injury in North-Carolina. Material and Methods: We focused on “lost-time injuries” defined as accidents leading to financial compensation, using exhaustive work injury claims for private sector employees over the 2006-2012 period in France. At-risk population counts were primarily extracted from detailed census data. We estimated a standardized work-injury ratio (SIRx) using inverse probability weighting, with non-managers as the reference population, stratifying on industry. We used the method flexibly with alternative at-risk population based on exhaustive administrative data, then looking at severe injuries. Results: The rate of lost-time injury was more than ten times higher in non-managers (4 031/100 000p.y.) as compared to managers (365/100 000p.y.) overall, based on 4 670 620 accidents registered over the study period. This corresponded to a SIRx of 11.4 [6.8;14.5]. A ratio above 1 indicates work environments where non-managers are exposed to higher risks compared to their manager counterparts, adjusting for the age structure of the workforce. Our results show that the most pronounced differences occurred in manufacturing industries, as well as transportation and warehousing, with SIRx above 12. Conclusion: The gap in work injuries is large and varies according to the social division of work and hazards which is highly dependent on factors such as trade sector, company size, and actual job content. These findings have policy implications as they underscore the importance of workplace equity and the need to improve health and safety for non-managers in key industries in France.