title: The effect of a brief action planning intervention on adherence to double-blind study medication, compared to a standard trial protocol, in the Atorvastatin in Factorial with Omega EE90 Risk Reduction in Diabetes (AFORRD) clinical trial: A cluster randomised sub-study.
abstract: OBJECTIVE
  Clinical trial patients are highly motivated but may encounter difficulty in taking study medication regularly when treatment burden is substantial. We assessed a brief behavioural intervention, given in addition to a standard trial protocol.
  
  
  METHODS
  We performed a two-arm adherence sub-study within a twelve-month randomised controlled drug trial evaluating the impact of statin and/or omega-3 EE90 treatment in 800 patients with type 2 diabetes. Fifty-nine United Kingdom general practices were cluster-randomised to action-planning or control groups. The former delivered an initial written exercise prompting participants to formulate action-plans to take study medication regularly, with brief nurse encouragement to use action-plans at later visits, whilst the latter followed the standard trial protocol. The primary outcome was proportion of days on which study medication were taken as intended measured by electronic medication containers.
  
  
  RESULTS
  Adjusted mean (95% CI) proportion of days with medication taken as intended was 79.3% (76.3-82.3%)for the 30 action-planning practices (321 participants), compared with 78.5% (75.8-81.1%) for 27 control group practices (426 participants, with a mean intervention effect of 0.9%, 95% CI -3.1% to +4.9%, p=0.67). Adjusted odds ratios for ⩾80% trial medication adherence for action-planning compared with control practices were 1.29 (0.90-1.84) and 1.38 (0.96-1.99) respectively.
  
  
  CONCLUSIONS
  Low-intensity action-planning interventions used alone are unlikely to have a clinically important impact on medication adherence, particularly in a clinical trial setting. These findings, do not exclude their contribution, as part of a multifactorial intervention, to improving treatment adherence. ISRCTN number 76737502.
authors: Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK; Diabetes Trials Unit, Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, UK. Electronic address: andrew.farmer@phc.ox.ac.uk.
authors: Andrew J
authors: AJ
authors: Farmer
authors: Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.
authors: Jason
authors: J
authors: Oke
authors: Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK.
authors: Wendy
authors: W
authors: Hardeman
authors: Diabetes Trials Unit, Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, UK.
authors: Lynne
authors: L
authors: Tucker
authors: Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK.
authors: Stephen
authors: S
authors: Sutton
authors: Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK.
authors: Ann-Louise
authors: AL
authors: Kinmonth
authors: MRC Epidemiology Unit, University of Cambridge, Cambridge, UK.
authors: Simon
authors: S
authors: Griffin
authors: Diabetes Trials Unit, Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, UK.
authors: Rury R
authors: RR
authors: Holman
mesh_terms: D000368:Aged; D000069059:Atorvastatin / Q000627:therapeutic use*; D001521:Behavior Therapy / Q000379:methods*; D016022:Case-Control Studies; D002985:Clinical Protocols; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy*; D004311:Double-Blind Method; D018479:Early Intervention, Educational; D005260:Female; D006293:Health Promotion; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use; D008297:Male; D055118:Medication Adherence; D008875:Middle Aged; D009042:Motivation; D040242:Risk Reduction Behavior; D006113:United Kingdom
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D000069059:Atorvastatin
keywords: Action planning; Adherence; Adults; Omega-3 EE90; Statin; Type 2 diabetes