Health Impact Assessment is a method of estimating the potential health effects of the implementation of a plan, which may or may not be aimed at influencing the health of the population. The likely positive effects are weighed up against the negative effects. A detailed guide and more information about HIA in London is available from the London Health Strategy website

Back to top ^^

At its simplest HIA is a way of looking at the health consequences of a wide range of policy, programme, or project decisions. Thus it may be applied to looking at transport, economic development, education, housing, regeneration etc - in fact just about anything that affects the way people live their lives will have some sort of effect on their health.

The assessment may be carried out prospectively, such that its conclusions can inform the decision as to whether the plan should go ahead. It can be carried out concurrently to influence decision makers during the life of the programme or policy. The assessment can also be carried out retrospectively, at a suitable time after the implementation of the plan, to assess the impact on health. If the plan is aimed at influencing health, a retrospective health impact assessment is a form of evaluation. However, in most cases, health is not the primary objective of a plan; whereas evaluation compares outcomes with what was intended, HIA examines a broad range of positive and negative effects.

The approach has its origins in environmental impact assessment. The difference is that influences on health other than the environment are considered. There are many models available which consider possible health effects. An example is Lalonde's health fields:

Back to top ^^

Overall the aim of health impact assessment is to allow a systematic consideration of likelyoutcomes regarding the health of a population to be incorporated into decision-making. Obviously the scale of any proposed plan can influence its likely effect on health, and therefore the need for a full health impact assessment. Hence the idea of 'screening' proposals to identify those for which a health impact assessment would be most useful.

The steps involved in an HIA are outlined in Introducing health impact assessment (HIA):

Stage 1: Often called screening - is the stage when you decide whether an HIA is likely to be the best way to ensure health and equity issues are address appropriately in a given situation.

Stage 2: Often referred to as scoping - is the when you decide how to undertake your HIA and begin to do your planning.

Stage 3: Often called the appraisal or assessment stage - is when you identify and consider a range of evidence about what the likely impacts of health may be, including research evidence and the qualitative evidence from stakeholders.

Stage 4: Often called developing and prioritising recommendations - is when you formulate and prioritise specific recommendations for the decision makers based on best available evidence.

Stage 5: There needs to be continued work with decision makers after the HIA is completed to reinforce the value of evidence based recommendations and to support the implementation of recommendations they agree to adopt within the proposal.

Stage 6: ongoing evaluation and monitoring to assess whether recommendations were adopted and to look at ways of monitoring long-term health and equity outcomes.

Back to top ^^

Click Here to use our HIA calculator to help work through how much money and time your HIA might take to do. As this is a new resource, we are interested in your comments to help us develop it further in future. Please forward any feedback to at the LHO.

Back to top ^^

The LHO was commissioned by Transport for London in October 2004 to conduct HIA on the proposed western extension to the central London congestion charging zone. Click Here for the final HIA report.

Back to top ^^

The contacts listed below have expertise in the field of HIA. They are not all available to be commissioned to conduct HIA. Click Here for a list of HIA consultants available to be commissioned to conduct HIA.

Click Here for points to consider and things to ask for when commissioning an HIA consultant.

Back to top ^^

• Mindell J, Ison E, Joffe M. A glossary for health impact assessment.
  Journal of Epidemiology and Community Health 2003;57 (9):647-651.
  http://jech.bmjjournals.com/current.shtml#GLOSSARY or
  http://jech.bmjjournals.com/cgi/reprint/57/9/647.pdf
• Mindell J, Joffe M. Health Impact Assessment in relation to other forms of impact assessment.
  Journal of Public Health Medicine 2003; 25 (2):107-112.
  http://pubmed.oupjournals.org/cgi/reprint/25/2/107.pdf
• Joffe M, Mindell J. A framework for the evidence base to support health impact assessment.
  Journal of Epidemiology and Community Health 2002; 56 (2): 132-138.
• Mindell J, Hansell A, Morrison D, Douglas M, Joffe M.
  What do we need for robust and quantitative health impact assessment? Journal of Public Health Medicine 2001; 23 (3): 173-178. http://pubmed.oupjournals.org/cgi/reprint/23/3/173.pdf
• Cave, B. and Curtis, S. Health impact assessment for regeneration projects. Volume I: A practical guide.
  London: East London and the City Health Action Zone and Queen Mary University of London, 2001.
  www.geog.qmul.ac.uk/health/
• Lock, K. (2000). "Health Impact Assessment." BMJ 320(2000): 1395-8. www.bmj.com
• Parry, J. and Stevens, A. (2001). "Prospective Health Impact Assessment: pitfalls, problems, and possible ways forward." BMJ 323: 1177-1182. www.bmj.com
• Scott-Samuel, A., Birley, M.H., et al. The Merseyside guidelines for health impact assessment. Liverpool: Liverpool Public Health Observatory, University of Liverpool: 20, 1998. http://www.ihia.org.uk/index.html
• European Centre for Health Policy. Health Impact Assessment: Gothenburg Consensus Paper. Brussels: WHO, 1999. http://www.who.dk/document/PAE/Gothenburgpaper.pdf

Date	Title	Format	View
Jul 2008	HIA consultants available to be commissioned to conduct health impact assessment
24 Oct 2006	HIA in the UK: a snapshot
5 Dec 2005	A report of a health impact assessment of the Mayor's draft transport strategy by the London Health Commission
5 Dec 2005	Health impact assessment: draft air quality strategy
5 Dec 2005	Health impact assessment: draft energy strategy
30 Sep 2005	HIA Cost Calculator
1 Sep 2005	Health Imapct Assessment – Draft Ambient Noise Strategy
1 Sep 2005	Health impact assessment of the Mayor's draft children and young people's strategy
1 Sep 2005	Health impact assessment: draft biodiversity strategy
1 Sep 2005	Health impact assessment: draft economic development strategy
1 Sep 2005	Health impact assessment: draft London plan
1 Sep 2005	Health impact assessment: the Mayor’s draft municipal waste management strategy
1 Mar 2003	Health impact assessment: draft culture strategy

Back to top ^^