Guideline Impact Factor – A new indicator to assess journals cited in medical guidelines

Despite of its many limitations, the Journal Impact Factor (JIF) is widely used to evaluate research institutions and individual researchers. Using references from 41 German medical guidelines we show that clinical relevance as assessed by guideline authors is uncorrelated to the JIF suggesting that a journal’s clinical relevance is independent of its JIF. As a consequence, evaluations solely relying on the JIF end up under-valuing clinically important research. We therefore propose a Guideline Impact Factor (GLIF) quantifying the relevance of journals for medical guideline development as an independent quality criterion for journals.