title: Evaluation of a complex intervention to improve primary care prescribing: a phase IV segmented regression interrupted time series analysis.
abstract: BACKGROUND
  It is uncertain whether improvements in primary care high-risk prescribing seen in research trials can be realised in the real-world setting.
  
  
  OBJECTIVE
  To evaluate the impact of a 1-year system-wide phase IV prescribing safety improvement initiative, which included education, feedback, support to identify patients to review, and small financial incentives.
  
  
  METHODS
  An interrupted time series analysis of targeted high-risk prescribing in all 56 general practices in NHS Forth Valley, Scotland, was performed. In 2013-2014, this focused on high-risk non-steroidal anti-inflammatory drugs (NSAIDs) in older people and NSAIDs with oral anticoagulants; in 2014-2015, it focused on antipsychotics in older people.
  
  
  METHODS
  The primary analysis used segmented regression analysis to estimate impact at the end of the intervention, and 12 months later. The secondary analysis used difference-in-difference methods to compare Forth Valley changes with those in NHS Greater Glasgow and Clyde (GGC).
  
  
  RESULTS
  In the primary analysis, downward trends for all three NSAID measures that were existent before the intervention statistically significantly steepened following implementation of the intervention. At the end of the intervention period, 1221 fewer patients than expected were prescribed a high-risk NSAID. In contrast, antipsychotic prescribing in older people increased slowly over time, with no intervention-associated change. In the secondary analysis, reductions at the end of the intervention period in all three NSAID measures were statistically significantly greater in NHS Forth Valley than in NHS GGC, but only significantly greater for two of these measures 12 months after the intervention finished.
  
  
  CONCLUSIONS
  There were substantial and sustained reductions in the high-risk prescribing of NSAIDs, although with some waning of effect 12 months after the intervention ceased. The same intervention had no effect on antipsychotic prescribing in older people.
authors.affiliation: Division of Population Health Sciences, School of Medicine, University of Dundee, Dundee, Scotland.
authors.forename: Sean
authors.initials: S
authors.lastname: MacBride-Stewart
authors.affiliation: Division of Population Health Sciences, School of Medicine, University of Dundee, Dundee, Scotland.
authors.forename: Charis
authors.initials: C
authors.lastname: Marwick
authors.affiliation: Dollar Health Centre, Dollar, Clackmannanshire, Scotland.
authors.forename: Neil
authors.initials: N
authors.lastname: Houston
authors.affiliation: Falkirk Community Hospital, Falkirk, Scotland.
authors.forename: Iain
authors.initials: I
authors.lastname: Watt
authors.affiliation: Division of Population Health Sciences, School of Medicine, University of Dundee, Dundee, Scotland.
authors.forename: Andrea
authors.initials: A
authors.lastname: Patton
authors.affiliation: Division of Population Health Sciences, School of Medicine, University of Dundee, Dundee, Scotland.
authors.forename: Bruce
authors.initials: B
authors.lastname: Guthrie
mesh_terms: D000328:Adult; D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D000925:Anticoagulants / Q000627:therapeutic use; D014150:Antipsychotic Agents / Q000627:therapeutic use; D011307:Drug Prescriptions / Q000706:statistics & numerical data*; D017723:Drug Utilization Review; D058006:General Practice / Q000706:statistics & numerical data*; D006801:Humans; D008875:Middle Aged; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D012606:Scotland / Q000453:epidemiology
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000925:Anticoagulants; D014150:Antipsychotic Agents
keywords: antipsychotic drugs; general practice; high-risk prescribing; interrupted time series analysis; non-steroidal anti-inflammatory drugs; quality improvement