Google Scholar coverage of a multidisciplinary field

This paper evaluates the content of Google Scholar and seven other databases (Academic Search Elite, AgeLine, ArticleFirst, GEOBASE, POPLINE, Social Sciences Abstracts, and Social Sciences Citation Index) within the multidisciplinary subject area of later-life migration. Each database is evaluated with reference to a set of 155 core articles selected in advance—the most important studies of later-life migration published from 1990 to 2000. Of the eight databases, Google Scholar indexes the greatest number of core articles (93%) and provides the most uniform publisher and date coverage. It covers 27% more core articles than the second-ranked database (SSCI) and 2.4 times as many as the lowest-ranked database (GEOBASE). At the same time, a substantial proportion of the citations provided by Google Scholar are incomplete (32%) or presented without abstracts (33%).