Browsing by Author "Richiardi L"

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    Association between recruitment methods and attrition in Internet-based studies.
    (PUBLIC LIBRARY SCIENCE, 2014) Bajardi P; Paolotti D; Vespignani A; Eames K; Funk S; Edmunds WJ; Turbelin C; Debin M; Colizza V; Smallenburg R; Koppeschaar C; Franco AO; Faustino V; Carnahan A; Rehn M; Merletti F; Douwes J; Firestone R; Richiardi L
    Internet-based systems for epidemiological studies have advantages over traditional approaches as they can potentially recruit and monitor a wider range of individuals in a relatively inexpensive fashion. We studied the association between communication strategies used for recruitment (offline, online, face-to-face) and follow-up participation in nine Internet-based cohorts: the Influenzanet network of platforms for influenza surveillance which includes seven cohorts in seven different European countries, the Italian birth cohort Ninfea and the New Zealand birth cohort ELF. Follow-up participation varied from 43% to 89% depending on the cohort. Although there were heterogeneities among studies, participants who became aware of the study through an online communication campaign compared with those through traditional offline media seemed to have a lower follow-up participation in 8 out of 9 cohorts. There were no clear differences in participation between participants enrolled face-to-face and those enrolled through other offline strategies. An Internet-based campaign for Internet-based epidemiological studies seems to be less effective than an offline one in enrolling volunteers who keep participating in follow-up questionnaires. This suggests that even for Internet-based epidemiological studies an offline enrollment campaign would be helpful in order to achieve a higher participation proportion and limit the cohort attrition.
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    Heirarchical regression for multiple comparisons in a case-control study of occupational risks for lung cancer.
    (Public Library of Science, 11/06/2012) Corbin M; Richiardi L; Vermeulen R; Kromhout H; Merletti F; Peters S; Simonato L; Steenland K; Pearce NE; Maule M
    Background Occupational studies often involve multiple comparisons and therefore suffer from false positive findings. Semi-Bayes adjustment methods have sometimes been used to address this issue. Hierarchical regression is a more general approach, including Semi-Bayes adjustment as a special case, that aims at improving the validity of standard maximum-likelihood estimates in the presence of multiple comparisons by incorporating similarities between the exposures of interest in a second-stage model. Methodology/Principal Findings We re-analysed data from an occupational case-control study of lung cancer, applying hierarchical regression. In the second-stage model, we included the exposure to three known lung carcinogens (asbestos, chromium and silica) for each occupation, under the assumption that occupations entailing similar carcinogenic exposures are associated with similar risks of lung cancer. Hierarchical regression estimates had smaller confidence intervals than maximum-likelihood estimates. The shrinkage toward the null was stronger for extreme, less stable estimates (e.g., “specialised farmers”: maximum-likelihood OR: 3.44, 95%CI 0.90–13.17; hierarchical regression OR: 1.53, 95%CI 0.63–3.68). Unlike Semi-Bayes adjustment toward the global mean, hierarchical regression did not shrink all the ORs towards the null (e.g., “Metal smelting, converting and refining furnacemen”: maximum-likelihood OR: 1.07, Semi-Bayes OR: 1.06, hierarchical regression OR: 1.26). Conclusions/Significance Hierarchical regression could be a valuable tool in occupational studies in which disease risk is estimated for a large amount of occupations when we have information available on the key carcinogenic exposures involved in each occupation. With the constant progress in exposure assessment methods in occupational settings and the availability of Job Exposure Matrices, it should become easier to apply this approach.
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    Lung cancer risk in painters: results from the SYNERGY pooled case-control study consortium
    (BMJ Publishing Group Ltd, 2021-04) Guha N; Bouaoun L; Kromhout H; Vermeulen R; Brüning T; Behrens T; Peters S; Luzon V; Siemiatycki J; Xu M; Kendzia B; Guenel P; Luce D; Karrasch S; Wichmann H-E; Consonni D; Landi MT; Caporaso NE; Gustavsson P; Plato N; Merletti F; Mirabelli D; Richiardi L; Jöckel K-H; Ahrens W; Pohlabeln H; TSE LA; Yu IT-S; Tardón A; Boffetta P; Zaridze D; 't Mannetje A; Pearce N; Davies MPA; Lissowska J; Świątkowska B; McLaughlin J; Demers PA; Bencko V; Foretova L; Janout V; Pándics T; Fabianova E; Mates D; Forastiere F; Bueno-de-Mesquita B; Schüz J; Straif K; Olsson A
    OBJECTIVES: We evaluated the risk of lung cancer associated with ever working as a painter, duration of employment and type of painter by histological subtype as well as joint effects with smoking, within the SYNERGY project. METHODS: Data were pooled from 16 participating case-control studies conducted internationally. Detailed individual occupational and smoking histories were available for 19 369 lung cancer cases (684 ever employed as painters) and 23 674 age-matched and sex-matched controls (532 painters). Multivariable unconditional logistic regression models were adjusted for age, sex, centre, cigarette pack-years, time-since-smoking cessation and lifetime work in other jobs that entailed exposure to lung carcinogens. RESULTS: Ever having worked as a painter was associated with an increased risk of lung cancer in men (OR 1.30; 95% CI 1.13 to 1.50). The association was strongest for construction and repair painters and the risk was elevated for all histological subtypes, although more evident for small cell and squamous cell lung cancer than for adenocarcinoma and large cell carcinoma. There was evidence of interaction on the additive scale between smoking and employment as a painter (relative excess risk due to interaction >0). CONCLUSIONS: Our results by type/industry of painter may aid future identification of causative agents or exposure scenarios to develop evidence-based practices for reducing harmful exposures in painters.
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    Occupation and risk of upper aerodigestive tract cancer: The ARCAGE study
    (Wiley Online, 15/05/2012) Richiardi L; Corbin M; Marron M; Ahrens W; Pohlabeln H; Lagiou P; Minaki P; Agudo A; Castellsague X; Slamova A; Schejbalova M; Kjaerheim K; Barzan L; Talamini R; MacFarlane GJ; MacFarlane TV; Canova C; Simonato L; Conway DI; McKinney PA; Sneddon L; Thomson P; Znaor A; Healy CM; McCartan BE; Benhamou S; Bouchardy C; Hashibe M; Brennan P; Merletti F
    We investigated the association between occupational history and upper aerodigestive tract (UADT) cancer risk in the ARCAGE European case-control study. The study included 1,851 patients with incident cancer of the oral cavity, oropharynx, hypopharynx, larynx or esophagus and 1,949 controls. We estimated odds ratios (OR) and 95% confidence intervals (CI) for ever employment in 283 occupations and 172 industries, adjusting for smoking and alcohol. Men (1,457 cases) and women (394 cases) were analyzed separately and we incorporated a semi-Bayes adjustment approach for multiple comparisons. Among men, we found increased risks for occupational categories previously reported to be associated with at least one type of UADT cancer, including painters (OR = 1.74, 95% CI: 1.01-3.00), bricklayers (1.58, 1.05-2.37), workers employed in the erection of roofs and frames (2.62, 1.08-6.36), reinforced concreters (3.46, 1.11-10.8), dockers (2.91, 1.05-8.05) and workers employed in the construction of roads (3.03, 1.23-7.46), general construction of buildings (1.44, 1.12-1.85) and cargo handling (2.60, 1.17-5.75). With the exception of the first three categories, risks both increased when restricting to long duration of employment and remained elevated after semi-Bayes adjustment. Increased risks were also found for loggers (3.56, 1.20-10.5) and cattle and dairy farming (3.60, 1.15-11.2). Among women, there was no clear evidence of increased risks of UADT cancer in association with occupations or industrial activities. This study provides evidence of an association between some occupational categories and UADT cancer risk among men. The most consistent findings, also supported by previous studies, were obtained for specific workers employed in the construction industry. © 2011 UICC.
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    Using directed acyclic graphs to consider adjustment for socioeconomic status in occupational cancer studies.
    (B M J PUBLISHING GROUP, 2008-07) Richiardi L; Barone-Adesi F; Merletti F; Pearce N
    There is an ongoing debate on whether analyses of occupational studies should be adjusted for socioeconomic status (SES). In this paper directed acyclic graphs (DAGs) were used to evaluate common scenarios in occupational cancer studies with the aim of clarifying this issue. It was assumed that the occupational exposure of interest is associated with SES and different scenarios were evaluated in which (a) SES is not a cause of the cancer under study, (b) SES is not a cause of the cancer under study, but is associated with other occupational factors that are causes of the cancer, (c) SES causes the cancer under study and is associated with other causal occupational factors. These examples illustrate that a unique answer to the issue of adjustment for SES in occupational cancer studies is not possible, as in some circumstances the adjustment introduces bias, in some it is appropriate and in others both the adjusted and the crude estimates are biased. These examples also illustrate the benefits of using DAGs in discussions of whether or not to adjust for SES and other potential confounders.
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    Why has epidemiology not (yet) succeeded in identifying the origin of the asthma epidemic?
    (Oxford University Press, 2023-04-02) Antó JM; Pearce N; Douwes J; Garcia-Aymerich J; Pembrey L; Richiardi L; Sunyer J