Do breadcrumbs aid navigation and help users accomplish their goals?
Lazar & Eisenbrey (2000) studied efficiency in completing tasks on websites with different navigation options. Participants in their study completed tasks on three websites; some were given breadcrumbs as an option and others were not. On average, it took participants 60 seconds less time to complete tasks in sites with breadcrumb nav bars than in those without.
Hull's study (2004) supports Lazar & Eisenbrey's evidence. One goal of this study was to determine whether breadcrumb usage improved efficiency in finding items to purchase on the Wal*Mart website. Participant Group 1 received both exposure and instruction about the breadcrumbs, group 2 received only exposure, and group 3 was not given exposure nor instruction. Group 1 completed the same set of tasks in significantly less time with fewer page views than groups 2 and 3. Those who were educated about the breadcrumbs used them, and those who did completed tasks in less time than the others.
On the other hand, two studies performed in 2003 (Lida et. al.; Rogers et. al.) found no statistical evidence that breadcrumbs help users complete tasks with more precision or more efficiency. However, Rogers et. al. did report that those who used breadcrumbs reported a more accurate understanding of the hierarchical nature of the test site.
With conflicting evidence on both sides, it is impossible to assert with confidence that breadcrumb navigation significantly aids user navigation and helps users accomplish their goals. It is thus worth considering whether including breadcrumbs is at all detrimental to users. None of the studies cited here report evidence to that end.
Without a clear empirically tested indication either way on the efficacy issue, we might best turn to the advice of usability experts. Nielsen (2000) states that breadcrumbs help users interpret a product, seeing which family to which it belongs, and also allows them to navigate easily to a broader page higher in a hierarchy. He claims that breadcrumbs help to contextualize pages for users. Hudson (2004) outlines reasons why breadcrumbs are good for navigation, namely: they enable users to stay in a general area of interest without backing out to the homepage, it is otherwise hard to navigate backwards, and they help users understand a site's hierarchy. Finally, Krug (2000) believes breadcrumbs are "self-explanatory, they don't take up much room, and they provide a convenient, consistent way to do two of the things you need to do most often: back up a level or go Home."