The university guide published annually by the magazine US News and World Report, whose league tables routinely drive United States academics to distraction, is to be challenged by similar publications from rivals Time and Newsweek.

The US News guide called America's Best Colleges has virtually monopolised the market since its launch in 1983. This summer parents and prospective students can also choose from Time's The Best College for You and Newsweek's How to Get Into College.

Richard Detweiler, president of Hartwick College in New York state, and a persistent critic of journalistic college rankings, said: "US News has made a huge amount of money at very little real expense and the others have realised that."

Hartwick is one of a small number of colleges that refuse to cooperate with US News researchers.

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US News and World Report is relatively unknown abroad but has found a niche in consumer journalism where it can satisfy the American public's insatiable appetite for statistics.

Every summer, US News devotes a special issue to the college guide, which has proved a profitable way to boost sales in a journalistic lean season. Five hundred colleges are ranked by number in categories such as "Best universities" and "Best liberal-arts colleges". It publishes an accompanying 300-page book, with greater detail and wider coverage, which has an annual print run of about one million.

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In 1995, the US National Research Council ranked 3,634 doctoral programmes at US research universities in a 740-page work that was four years in the making.

But there has been no corresponding scientific assessment of undergraduate courses, and as a result it has been left largely to journalists. Money magazine has also published a guide, but US News is regarded as the Bible of the trade.

Its ranking system is largely based on statistical readings of answers to a questionnaire sent to colleges. Its coverage ranges from test scores for the entering class, to an institution's reputation among college officers nationwide, to expenditures per student, graduation rates, and even the percentage of alumni who give money.

David Webster, professor of education at Oklahoma State University and one of the few in favour of rankings, said: "American academics, as a rule, either 'dislike or detest' the rankings." A list of the adjectives used to describe them, which he once compiled, runs from amateurish, inaccurate and shallow to just plain wacko and totally bonkers.

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But college guides have proved difficult to ignore. Studies have shown that about half of all students consult them. Alvin Sanoff, editor of the US News guide, said: "I think that we have a reputation that we have worked to establish for openness, for seriousness, for willingness to change when people make good and valid suggestions."

Time and Newsweek will not have the benefit of US News's years of experience. Both are publishing their guides in collaboration with companies that offer training for the US Scholastic Assessment Test.

Time's 220-page book will include a self-assessment test for students and a CD-Rom to help with college applications. Newsweek's is 200 pages long and looks at more than 1,000 institutions. Spurred in part by the competition, US News has added 70 pages to its book, including figures on the level of debt of student graduates.