Tag: systematic review

Overadjustment – an important bias hiding in plain sight

Anita van Zwieten, Fiona M Blyth, Germaine Wong and Saman Khalatbari-Soltani

Epidemiologists are generally well equipped to design and conduct studies that minimise various types of bias, so as to obtain the most accurate estimates possible and therefore high-quality evidence. In observational studies, some types of bias, like confounding, have received a lot of attention, while others have been overlooked. One that has been neglected is overadjustment bias, which occurs when researchers adjust for an explanatory variable on the causal pathway from exposure to outcome when seeking to estimate the total effect.

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What are the long-term health effects of earthquakes? Meta-analysis results and implications for epidemiological practice

Alba Ripoll Gallardo, Barbara Pacelli and Elias Allara

authors

Population growth and urbanisation of seismic areas are leading to a constant increase in the health-related and economic toll of earthquakes. In 2014 alone, 324 natural disasters were reported worldwide, resulting in 141 million casualties and nearly $100 billion in damage. Geophysical disasters, including earthquakes, accounted for about 10% of these events.

Although the impact of earthquakes in the response phase – that is, immediately or shortly after the main seismic event – has been well studied, we have little knowledge of the effects of earthquakes in the medium and long term. This uncertainty may cause inefficient planning of post-earthquake epidemiological surveillance, resulting in potential underestimation of public health needs.

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Waterpipe smoking might be just as harmful as smoking cigarettes

Reem Waziry and Elie Akl

Elie_Akl[1] Reem Waziry headshotWaterpipe, also known as shisha, goza, narghile, arghile and hookah, is a traditional method for smoking tobacco. While it originated in Turkey, India and Iran, its use has spread on a global level over the past decade to the point of being labelled a global epidemic.

There are a number of explanations for the global spread of waterpipe tobacco smoking. First, people use it as a way to socialize, as it is smoked in groups. Second, the production of sweetened and flavoured tobacco (Maassel), resulting in aromatic and smooth smoke, can make it more appealing than cigarette smoking. Another major reason is a common misconception that waterpipe tobacco smoking is not harmful, or is less harmful than smoking cigarettes. Continue reading “Waterpipe smoking might be just as harmful as smoking cigarettes” →