TY - JOUR T1 - Healthy behaviours and COPD JF - European Respiratory Review JO - EUROPEAN RESPIRATORY REVIEW SP - 410 LP - 415 DO - 10.1183/09059180.00005414 VL - 23 IS - 134 AU - Isabella Annesi-Maesano AU - Nicolas Roche Y1 - 2014/12/01 UR - http://err.ersjournals.com/content/23/134/410.abstract N2 - In this issue of the European Respiratory Review, Young and Hopkins [1] elegantly discuss how beans (an important part of the Hispanic diet) could reduce systemic inflammation and, thereby, the risk of chronic obstructive pulmonary disease (COPD) and lung cancer, explaining the risk imbalance between Hispanics, African–Americans and non-Hispanic whites. As appropriately acknowledged by the authors, what they propose is a hypothesis, warranting confirmation in specific observational and interventional studies. The purpose of this editorial is to discuss some important issues evoked in their reasoning, focusing on COPD only. Altogether, the main question is: is causal inference between bean intake and reduction in the risk of COPD occurrence possible from available data and, if not, what would be needed to progress, considering possible confounders? In 1965, Sir Bradford Hill, an epidemiologist, proposed to consider the following criteria when assessing the causality of a relationship between two events/conditions [2]: 1) the strength of the association, as assessed by statistics (rate ratios, risk ratios and odds ratios); 2) consistency and repeatability of the association; 3) specificity of the relationship (one cause leads to one effect); 4) temporal relationship (the cause precedes the consequence); 5) presence of a dose–response relationship, i.e. greater exposure is associated with greater incidence of the effect; 6) biological plausibility; 7) coherence between epidemiological and biological/laboratory evidence; 8) experimental evidence; and 9) analogy with the effect of other, similar factors. Two other factors need to be considered: 1) the possible involvement of bias by confounding factors in the observed association(s) [3]; and 2) the specific issue of confirmation of observations by interventional approaches [4]. The need to consider the criteria of Hill [2] as a guide rather than as a definitive tool has been underlined … ER -