TY - JOUR T1 - The validity of recommendations from clinical guidelines: a survival analysis JF - Canadian Medical Association Journal JO - CMAJ SP - 1211 LP - 1219 DO - 10.1503/cmaj.140547 VL - 186 IS - 16 AU - Laura Martínez García AU - Andrea Juliana Sanabria AU - Elvira García Álvarez AU - Maria Mar Trujillo-Martín AU - Itziar Etxeandia-Ikobaltzeta AU - Anna Kotzeva AU - David Rigau AU - Arturo Louro-González AU - Leticia Barajas-Nava AU - Petra Díaz del Campo AU - Maria-Dolors Estrada AU - Ivan Solà AU - Javier Gracia AU - Flavia Salcedo-Fernandez AU - Jennifer Lawson AU - R. Brian Haynes AU - Pablo Alonso-Coello A2 - , Y1 - 2014/11/04 UR - http://www.cmaj.ca/content/186/16/1211.abstract N2 - Background: Clinical guidelines should be updated to maintain their validity. Our aim was to estimate the length of time before recommendations become outdated.Methods: We used a retrospective cohort design and included recommendations from clinical guidelines developed in the Spanish National Health System clinical guideline program since 2008. We performed a descriptive analysis of references, recommendations and resources used, and a survival analysis of recommendations using the Kaplan–Meier method.Results: We included 113 recommendations from 4 clinical guidelines with a median of 4 years since the most recent search (range 3.9–4.4 yr). We retrieved 39 136 references (range 3343–14 787) using an exhaustive literature search, 668 of which were related to the recommendations in our sample. We identified 69 (10.3%) key references, corresponding to 25 (22.1%) recommendations that required updating. Ninety-two percent (95% confidence interval 86.9–97.0) of the recommendations were valid 1 year after their development. This probability decreased at 2 (85.7%), 3 (81.3%) and 4 years (77.8%).Interpretation: Recommendations quickly become outdated, with 1 out of 5 recommendations being out of date after 3 years. Waiting more than 3 years to review a guideline is potentially too long. ER -