One type of conflict of interest is financial. It could be someone who received funding from a company with a vested interest in the study's outcome. Or that person has a relationship with the company that could lead to benefits in the future.

A recent analysis found t...

If you are looking at a clinical trial, a psychology study, or an animal study, it must be a randomized, placebo-controlled, double-blind study.

• Randomized: The participants in the study are randomly placed into the experimental group and the compari...

In science, "statistically significant" is the effect that can be picked up with a particular statistical tool called a p-value. A good p-value (or calculated probability) is arbitrary and can vary between scientific fields. The cut-off for statistically significant is a p-value ...

• The Impact Factor is the most commonly used metric to assess a scientific journal's influence. It counts the number of times a journal's papers have been mentioned in other papers, relative to their own output.
• You can find a journal's Impact Factor in the Journal ...

• Correlation: Scientists may find that two variables are correlated. They may be related, but it doesn't mean that one is causing the other. It could be a coincidence, or perhaps a third variable is causing both of the other two.
• Causation: Lots of ...

Studies can suffer from selection bias when people are recruited from a specific group that are not representative of the whole. Scientists select a smaller group to study, but the chosen set isn't random enough and is therefore somehow biased in favor of a specific outcome of th...

In a peer review system, independent, anonymous experts read over a paper submitted to a journal. They can recommend revisions to the text, new experiments that should be added, or even that the journal shouldn't publish the paper.

But reviewers aren't asked to ensure that...