Article Text

Download PDFPDF
Running along parallel lines: how political reality impedes the evaluation of public health interventions. A case study of exercise referral schemes in England
  1. S L Sowden1,
  2. R Raine1,2
  1. 1
    Health Care Evaluation Group, Department of Epidemiology and Public Health, London, UK
  2. 2
    Comprehensive Biomedical Research Centre UCLH/UCL, London, UK
  1. Ms S L Sowden, Health Care Evaluation Group, Department of Epidemiology and Public Health, 1–19 Torrington Place, London WC1E 6BT, UK; s.sowden{at}


Political decisions about the way that public health initiatives are implemented have a significant impact on the ability to evaluate their effectiveness. However, the influence of the political imperative has been little explored. This case study of key research, policy and practice events concerning one initiative, exercise referral schemes (ERSs), demonstrates that these schemes were encouraged to expand by the Department of Health (DH) before DH-funded evaluations had reported their findings and with little reference to National Institute for Health and Clinical Excellence (NICE) recommendations. Policy evolved in parallel rather than in conjunction with the development of evidence, and experimental evaluations in England are now unlikely. This is due to the comprehensive coverage of schemes, widespread assumptions of effectiveness, likely difficulties in obtaining research funding, indirect adverse consequences of dismantling schemes and lack of appropriate process and outcome data. Embedding a commitment to robust evaluation prior to universal adoption of new initiatives has been shown to be feasible by policy-makers in the international setting. This is required to prevent the establishment of public health interventions that do not work and may cause harm or widen health inequalities.

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


  • Funding: SS is funded by an ESRC/MRC PhD studentship. RR is partly funded by a DH Public Health Career Scientist Award.

  • Competing interests: None.

Linked Articles

  • In this issue
    Mauricio L Barreto