Article Text

Conceptualising interventions to enhance spread in complex systems: a multisite comprehensive medication review case study
  1. Laura Lennox1,2,
  2. Susan Barber1,2,
  3. Neil Stillman1,
  4. Sophie Spitters1,
  5. Emily Ward3,
  6. Vanessa Marvin3,
  7. Julie E Reed4,5
  1. 1 Primary Care and Public Health, Imperial College London, London, UK
  2. 2 NIHR ARC Northwest London, Chelsea and Westminster Hospital NHS Foundation Trust, London, UK
  3. 3 Pharmacy, Chelsea and Westminster Hospital NHS Foundation Trust, London, UK
  4. 4 School of Health and Welfare, Halmstad University, Halmstad, Sweden
  5. 5 Julie Reed Consultancy Ltd, London, UK
  1. Correspondence to Dr Julie E Reed, School of Health and Welfare, Halmstad University, Halmstad 301 18, Sweden; julie.reed{at}


Background Advancing the description and conceptualisation of interventions in complex systems is necessary to support spread, evaluation, attribution and reproducibility. Improvement teams can provide unique insight into how interventions are operationalised in practice. Capturing this ‘insider knowledge’ has the potential to enhance intervention descriptions.

Objectives This exploratory study investigated the spread of a comprehensive medication review (CMR) intervention to (1) describe the work required from the improvement team perspective, (2) identify what stays the same and what changes between the different sites and why, and (3) critically appraise the ‘hard core’ and ‘soft periphery’ (HC/SP) construct as a way of conceptualising interventions.

Design A prospective case study of a CMR initiative across five sites. Data collection included: observations, document analysis and semistructured interviews. A facilitated workshop triangulated findings and measured perceived effort invested in activities. A qualitative database was developed to conduct thematic analysis.

Results Sites identified 16 intervention components. All were considered essential due to their interdependency. The function of components remained the same, but adaptations were made between and within sites. Components were categorised under four ‘spheres of operation’: Accessibility of evidence base; Process of enactment; Dependent processes and Dependent sociocultural issues. Participants reported most effort was invested on ‘dependent sociocultural issues’. None of the existing HC/SP definitions fit well with the empirical data, with inconsistent classifications of components as HC or SP.

Conclusions This study advances the conceptualisation of interventions by explicitly considering how evidence-based practices are operationalised in complex systems. We propose a new conceptualisation of ‘interventions-in-systems’ which describes intervention components in relation to their: proximity to the evidence base; component interdependence; component function; component adaptation and effort.

  • complexity
  • healthcare quality improvement
  • implementation science
  • collaborative
  • breakthrough groups
  • clinical practice guidelines

Data availability statement

All data relevant to the study are included in the article or uploaded as supplemental information.

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See:

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Data availability statement

All data relevant to the study are included in the article or uploaded as supplemental information.

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  • Twitter @lauralennox3, @julie4clahrc

  • LL and JER contributed equally.

  • Contributors LL and JER contributed equally to the paper. JER and LL conceived of the study. LL and JER developed the research protocol with contributions from NS and SB. VM and EW led the CMR initiative. LL undertook the interviews. JER, LL and SB conducted the observations. SB conducted the focus group. NS performed the initial analysis of the data. LL and JER refined and developed the emerging themes and findings and conducted further analysis. SS, VM, EW and SB reviewed and commented on themes and findings. LL drafted the first version of the paper and JER made contributions to interpret results and develop the conceptual findings of the paper. All authors contributed to the development of the manuscript content. All authors read and approved the final manuscript.

  • Funding This research was funded by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care Northwest London (CLAHRC NWL), now recommissioned as NIHR Applied Research Collaboration NWL (ARC NWL). The research team also acknowledges the support of the NIHR Clinical Research Network (CRN). JR was also funded by a Health Foundation Improvement Science Fellowship.

  • Disclaimer The views expressed in this publication are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care.

  • Competing interests None declared.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.