How Quickly Do Systematic Reviews Go Out of Date? A Survival Analysis

Figure 2. The immediate decrease in survival at time zero reflects the 7 systematic reviews for which signals for updating
had already occurred at the time of publication. The low number of reviews at risk after 10 years reflects the fact that the
sample spanned 1995 to 2005 and censoring occurred on 1 September 2006. Thus, only reviews published before September 1996
and having no signals for updating could have more than 10 years of observation. Overall survival time (95% CI) free of signals for updating.
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Published online before print
July 16, 2007,
Ann Intern Med
August 21, 2007
vol. 147
no. 4
224-233