PT  - JOURNAL ARTICLE
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
ED  - ,
TI  - The validity of recommendations from clinical guidelines: a survival analysis
AID  - 10.1503/cmaj.140547
DP  - 2014 Nov 04
TA  - Canadian Medical Association Journal
PG  - 1211--1219
VI  - 186
IP  - 16
4099  - http://www.cmaj.ca/content/186/16/1211.short
4100  - http://www.cmaj.ca/content/186/16/1211.full
SO  - CMAJ2014 Nov 04; 186
AB  - 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 Our aim was to estimate the length of time before recommendations become outdated.Methods: We used a retrospective cohort design and included recommendations from clinical guidelines developed in the Spanish National Health System clinical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 This probability decreased at 2 (85.7%), 3 (81.3%) and 4 years (77.8%).Interpretation: Recommendations quickly become outdated, with 1 out of 5 recommendations being out of date after 3 years.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.