The Naked Truth about - Scientific - Models - Part 1

Previously, Risk Bites covered the basics of dose-response, and how this helps translate what we know about the potential of the something cause harm, to the probability of harm occuring. In a couple of weeks, we'll be looking more closely as dose-response relationships. But in between, we need to say few things about models. Talking about models can get tricky, Ask ten people what a model is, and you'll likely get ten different answers. To some, it's something they'd make out of legos or modeling clay. Or it could be a scale model of a planned new building. To others, it's a naked dude posing in front of an art class, or a slightly less-naked dude posing in a fashion magazine. It could even be a stick figure drawn to illustrates some point - what that point may be is might not always obvious. And then you've got us scientists. We use the word "model" in so many different ways that we occasionally get ourselves tied up in linguistic knots. To some scientists, a model is a Heath-Robinson lashup that demonstrates some process - the mechanics of walking, perhaps. Or it could be a conceptual idea that sheds light on reality. To others a model is a complex mathematical expression that describes something, or a computer model that is designed to predict behavior - such as the weather, or what you'll most likely to buy at the grocery store. In some cases, even animals are described as models - especially when those animals are used to investigate how the stuff we're exposed to might affect our health. In other words, the word "model" can mean very different things to different people. And this can lead to some awkward misunderstandings. The good news is that models typically have a couple of basic things in common. Whether you are talking haute coture or climate change, models usually represent something else in a way that offers insight into that that "something," and allows predictions to be made about how about that "something" will behave under different conditions. Fashion models for instance offer insight into designer clothes and allow protections on fashion trends. And climate change models provide insight into what influences the climate and predictions on how it will change in the future. As a result, models are very powerful tools. This is a specially so in dose-response, where they are used to connect what we are exposed to, to how this might affect our health. But models have their limitations. And without understanding these limitations, they can be rather dangerous. Next week's Risk Bites will look more at understanding and working with the limitations of models, before diving further into dose- response relationships. Until then, stay safe.