The scientific community needs to be aware of the limitations of Google Scholar's personalized citation reports. Clicking on 'My citations' on the site may offer a nice ego boost, but I would not recommend using the reports for decisions that could affect careers.

Google Scholar overestimates the number of citable articles (in comparison with formal citation services such as Scopus and Thomson Reuters) because of the automated way it collects data, including 'grey' literature such as theses. For my own publications, for example, Google Scholar yields 38% more citations and boosts the h-index by 26%.

A citation report for one of my articles revealed that Google Scholar had counted as independent citations four web pages on which authors had posted copies of their articles, plus one listing only an article title; and one to a paper in which my name didn't appear. Personalized searches by my colleagues exposed comparable errors.

These drawbacks might also allow unscrupulous individuals to use such tactics to inflate their citation reports, particularly as independent vetting is blocked by password access.