Cause and correlation are terms that are often confused or used incorrectly, particularly the former. This is an unfortunate thing for people who ever listen to a news report or read a newspaper. If you’ve followed the many things that have been reported as causes of cancer, you might never eat, drink, or leave your home again. When we hear that there might be a link between one thing and another, we often mistakenly assume that one thing causes the other.

The main difference between cause and correlation is the strength and degree to which two things are related and the certainty with which anyone can establish a causal relationship. Essentially when you say one thing causes another, you are saying that there is a direct line between that one thing and the result. Cause means that an action will always have a predictable reaction.

When you define correlation, the terms cause and correlation become easier to understand. If you see a correlation between two things, you can see that there is a relationship between those two things. One thing doesn’t necessarily result in the other thing occurring, but it may increase likelihood that something will occur.

Understanding the difference of cause and correlation can be helped by an example. You can, perhaps, examine the statement: “Violent video games cause violent behavior.” According to all research on this matter, this statement is not true, due to the use of the word causes in the sentence. Research has shown that violent video games may influence violent behavior.

It also shows that a number of different factors may be responsible for a person being violent, among them, poorer socioeconomic status, mental illness, abusive childhoods, and bad parenting. You cannot say violent video games are the cause of violence. In order to make the above statement, you’d have to be able to prove that everyone who ever played a violent video game subsequently exhibited violence.

Instead, what you can say, and what has been studied, is the correlation between violent video games and violent behavior. Researchers have shown that there is a connection/correlation there. Such games may influence others to act in more aggressive ways but they are not the sole factor and sometimes not even a factor for predicting violence. Thus there’s a correlation there, which should be considered, but there is no cause factor. Plenty of people were violent, prior to the advent of video games, thus if you’re deciding between cause and correlation here, you must choose correlation.

In some ways, it can be almost impossible, except in extremely controlled circumstances to say any one thing causes something else, especially when you’re dealing with human health or behavior. You can, in limited ways, make blanket cause/effect statements about some things. For example, heating water to a certain temperature causes it to boil. This is a specific cause/effect relationship that no one would dispute.

Yet it can be helpful to understand the difference between cause and correlation since we are often barraged with information about things that may pose health risks to us. What most researchers arrive at in research is that some things, for instance, alcoholism and cancer are connected or co-related. Alcoholism may increase your risk of getting cancer, but it does not, in and of itself, cause cancer.

When you hear about the causes of disease, it’s important to be skeptical. Scientists define correlations all the time, and unfortunately, news media loves to call these causes, since they then translate to a much more dramatic story. Read or listen carefully for qualifying words that suggest correlation like “may,” “might increase,” “could have an effect,” to separate the differences between cause and correlation.