title: Implementation of a nurse-led behaviour change intervention to support medication taking in type 2 diabetes: beyond hypothesised active ingredients (SAMS Consultation Study).
abstract: BACKGROUND
  Implementation of trial interventions is rarely assessed, despite its effects on findings. We assessed the implementation of a nurse-led intervention to facilitate medication adherence in type 2 diabetes (SAMS) in a trial against standard care in general practice. The intervention increased adherence, but not through the hypothesised psychological mechanism. This study aimed to develop a reliable coding frame for tape-recorded consultations, assessing both a priori hypothesised and potential active ingredients observed during implementation, and to describe the delivery and receipt of intervention and standard care components to understand how the intervention might have worked.
  
  
  METHODS
  211 patients were randomised to intervention or comparison groups and 194/211 consultations were tape-recorded. Practice nurses delivered standard care to all patients and motivational and action planning (implementation intention) techniques to intervention patients only. The coding frame was developed and piloted iteratively on selected tape recordings until a priori reliability thresholds were achieved. All tape-recorded consultations were coded and a random subsample double-coded.
  
  
  RESULTS
  Nurse communication, nurse-patient relationship and patient responses were identified as potential active ingredients over and above the a priori hypothesised techniques. The coding frame proved reliable. Intervention and standard care were clearly differentiated. Nurse protocol adherence was good (M (SD) = 3.95 (0.91)) and competence of intervention delivery moderate (M (SD) = 3.15 (1.01)). Nurses frequently reinforced positive beliefs about taking medication (e.g., 65% for advantages) but rarely prompted problem solving of negative beliefs (e.g., 21% for barriers). Patients' action plans were virtually identical to current routines. Nurses showed significantly less patient-centred communication with the intervention than comparison group.
  
  
  CONCLUSIONS
  It is feasible to reliably assess the implementation of behaviour change interventions in clinical practice. The main study results could not be explained by poor delivery of motivational and action planning components, definition of new action plans, improved problem solving or patient-centred communication. Possible mechanisms of increased medication adherence include spending more time discussing it and mental rehearsal of successful performance of current routines, combined with action planning. Delivery of a new behaviour change intervention may lead to less patient-centred communication and possible reduction in overall trial effects.
  
  
  BACKGROUND
  ISRCTN30522359.
authors.affiliation: Primary Care Unit, Institute of Public Health, Forvie Site, University of Cambridge School of Clinical Medicine, Cambridge Biomedical Campus, Box 113, CB2 0SR Cambridge, UK. wh207@medschl.cam.ac.uk.
authors.forename: Wendy
authors.initials: W
authors.lastname: Hardeman
authors.forename: Laura
authors.initials: L
authors.lastname: Lamming
authors.forename: Ian
authors.initials: I
authors.lastname: Kellar
authors.forename: Anna
authors.initials: A
authors.lastname: De Simoni
authors.forename: Jonathan
authors.initials: J
authors.lastname: Graffy
authors.forename: Sue
authors.initials: S
authors.lastname: Boase
authors.forename: Stephen
authors.initials: S
authors.lastname: Sutton
authors.forename: Andrew
authors.initials: A
authors.lastname: Farmer
authors.forename: Ann Louise
authors.initials: AL
authors.lastname: Kinmonth
mesh_terms: D000368:Aged; D059019:Clinical Coding; D003142:Communication; D003376:Counseling / Q000379:methods*; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy*; D005260:Female; D015438:Health Behavior; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D008297:Male; D055118:Medication Adherence; D008875:Middle Aged; D009042:Motivation; D009723:Nurse-Patient Relations; D009726:Nurses; D014743:Videotape Recording
chemical_list: D007004:Hypoglycemic Agents