title: Updated recommendations: an assessment of NICE clinical guidelines.
abstract: BACKGROUND
  Updating is important to ensure clinical guideline (CG) recommendations remain valid. However, little research has been undertaken in this field. We assessed CGs produced by the National Institute for Health and Care Excellence (NICE) to identify and describe updated recommendations and to investigate potential factors associated with updating. Also, we evaluated the reporting and presentation of recommendation changes.
  
  
  METHODS
  We performed a descriptive analysis of original and updated CGs and recommendations, and an assessment of presentation formats and methods for recording information. We conducted a case-control study, defining cases as original recommendations that were updated ('new-replaced' recommendations), and controls as original recommendations that were considered to remain valid ('not changed' recommendations). We performed a comparison of main characteristics between cases and controls, and we planned a multiple regression analysis to identify potential predictive factors for updating.
  
  
  RESULTS
  We included nine updated CGs (1,306 recommendations) and their corresponding original versions (1,106 recommendations). Updated CGs included 812 (62%) recommendations 'not reviewed', 368 (28.1%) 'new' recommendations, 104 (7.9%) 'amended' recommendations, and 25 (1.9%) recommendations reviewed but unchanged. The presentation formats used to indicate the changes in recommendations varied widely across CGs. Changes in 'amended', 'deleted', and 'new-replaced' recommendations (n = 296) were reported infrequently, mostly in appendices. These changes were recorded in 167 (56.4%) recommendations; and were explained in 81 (27.4%) recommendations. We retrieved a total of 7.1% (n = 78) case recommendations ('new-replaced') and 2.4% (n = 27) control recommendations ('not changed') in original CGs. The updates were mainly from 'Fertility CG', about 'gynaecology, pregnancy and birth' topic, and 'treatment' or 'prevention' purposes. We did not perform the multiple regression analysis as originally planned due to the small sample of recommendations retrieved.
  
  
  CONCLUSIONS
  Our study is the first to describe and assess updated CGs and recommendations from a national guideline program. Our results highlight the pressing need to standardise the reporting and presentation of updated recommendations and the research gap about the optimal way to present updates to guideline users. Furthermore, there is a need to investigate updating predictive factors.
authors.affiliation: Institute of Biomedical Research (IIB Sant Pau), Barcelona, Iberoamerican Cochrane Centre, Hospital de la Santa Creu i Sant Pau, Pavelló 18 C/Sant Antoni Mª Claret 167, Barcelona, Catalunya 08025, España. laura.martinez.garcia@cochrane.es.
authors.forename: Laura
authors.initials: L
authors.lastname: Martínez García
authors.forename: Emma
authors.initials: E
authors.lastname: McFarlane
authors.forename: Steven
authors.initials: S
authors.lastname: Barnes
authors.forename: Andrea Juliana
authors.initials: AJ
authors.lastname: Sanabria
authors.forename: Pablo
authors.initials: P
authors.lastname: Alonso-Coello
authors.forename: Philip
authors.initials: P
authors.lastname: Alderson
mesh_terms: D019317:Evidence-Based Medicine; D006801:Humans; D033181:Information Dissemination; D017410:Practice Guidelines as Topic; D013222:State Medicine / Q000592:standards*; D006113:United Kingdom