Tobacco harm reduction (THR), especially in the context of electronic cigarette (EC) research, remains highly contested within public health, often due to studies compromised by methodological flaws. These shortcomings in study design, analysis, terminology, or interpretation can distort scientific record, erode public trust, and generate misleading or uncritical media coverage and policy reports. These challenges become especially consequential when flawed evidence is aggregated and amplified through meta-analyses, which play a central role in shaping policy and clinical guidance.
In this issue of Internal and Emergency Medicine, Rodu and colleagues critically assess a widely cited 2024 meta-analysis by Glantz et al., published in NEJM Evidence. Glantz and coauthors concluded that e-cigarette use is associated with disease odds similar to those of cigarette smoking for cardiovascular conditions, and still substantial, though lower, for asthma, COPD, and oral diseases. Rodu et al. identify major methodological flaws that call these conclusions into question. This underlines the urgent need for rigorous and transparent evidence synthesis in tobacco harm reduction science.