Do users notice breadcrumbs? If so, do they understand their function?
In 2000, Lazar & Eisenbrey reported that from their informal questioning, "most people actually do not look at nav bars. They feel more comfortable just going back to the homepage and working their way through the site." Of their 67 subjects, about one-third said they did not find the breadcrumbs useful, however, only a very small percentage reported wanting to eliminate them altogether. Based on their survey, most people do not mind having the breadcrumbs present, even if they choose not to use them.
Rogers and Chaparro (2003) found that of their 30 participants who were presented a system with breadcrumbs, 40% of them clicked on breadcrumb links at least 5 times in the course of their information retrieval tasks. Information was not gathered in terms of how many actually noticed the breadcrumbs, but the fact that nearly half actually utilized them insinuates that more than half would be able to acknowledge that they were present on the site. This is not consistent with Lazar & Eisenbrey's findings, however, Rogers & Chaparro's study was performed three years later, and breadcrumbs were likely to be much less commonplace in 2000. Also of note in this study is the authors' recommendation that breadcrumb trails be positioned below the main title rather than at the top of the page, based on higher usage statistics under this condition.
In research by Lida et. al. (2003), 79 participants completed information-seeking tasks in two sites: Google and OfficeMax. Both sites utilize breadcrumb navigation. When completed, participants were asked whether they remembered seeing breadcrumbs; 57 (72.2%) recalled seeing them on Google, but only 29 (36.7%) recalled them on the OfficeMax site. This leads one to suppose that differences in a site's purpose or a site's design and the conventions used in presenting breadcrumbs can trigger better or worse visibility.
Hudson (2004) acknowledges visibility problems by asserting that users ignore breadcrumbs for many reasons: they are not widely and universally utilized, they are sometimes not used consistently even within the same site, and designers often hide them outside of the main content area or fail to make links obvious.
Krug (2000) advocates for using the words "You Are Here:" to the left of breadcrumbs to more clearly and plainly state their purpose.
Perhaps most the most illuminating of the research in this area is Hull's 2004 study that revealed that when given minimal training about and exposure to breadcrumbs, people are much more apt to notice and use them effectively. Colter et. al. revealed in 2002 that less than 20% of commercial sites use breadcrumbs. Despite information on whether this number has increased in recent years, one may presume that if breadcrumbs are becoming more commonplace, users will naturally be more educated about them, be quicker to notice their presence, and will understand their function. Hudson (2004) hints that users will eventually "catch up with the technology."