Empirical methods are the means by which scientists gather information about the world in order to develop theories. These include experiment, disclosure for peer review, and other ways in which theories are assessed by scientists. The term quasi-empirical methods evolved to describe aspects of the scientific method which are not amenable to disproof by experiment. These are now widely recognized to constitute much of what is loosely called 'scientific consensus', as some theories are not amenable to direct experimental invalidation, or indeed controlled experiment.
See also: hypothetico-deductive method.