Antony MorganAssociate Director

Centre for Public Health Excellence

Evidence Based Guidance for Public Health and the role of NICE -Purpose, Process and Issues

What is NICE?

The National Institute for Health and Clinical Excellence (NICE) is

the independent organisation responsible for providing national

guidance on the promotion of good health and the prevention and

treatment of ill health.

• Public health – guidance on the promotion of good health and the prevention of ill health – for those working in the NHS, local authorities and the wider public and voluntary sector.

• Health technologies – guidance on the use of new and existing medicines, treatments and procedures within the NHS.

• Clinical practice – guidance on the appropriate treatment and care of people with specific diseases and conditions within the NHS.

Programme guidance: key stages

• Scoping• Development• Validation• Publication

• Committees (PHIAC, Programme Development Groups)

• Stakeholders• Timeframes

Scopes aim to specify

• The intervention

• The outcome the assumed mechanism/mediator/link between intervention and outcome

• The research questions

• Approach to dealing with equity

• Current policy and practice context

• Conceptual model of how it works

Development: reviewing the evidence• Extensive use of reviews and primary

research– Rapid reviews– assess quality and strength of evidence– assess applicability

• Economic appraisal– economic evaluations and modelling

Key questions

• What is effective?

• What is ineffective?

• What is harmful or dangerous?

Age, sex & hereditary

factorsAgriculture

and food

Production

Education

Work environment

Housing

Health

care

services

Water & sanitation

Unemployment

Living & working conditions

Finding, collating and synthesising evidence

• Broad spectrum of possibilities.

• Quality of the research, not privileging types of or hierarchies of evidence

Areas of enquiry: Our reviews aim to address the following areas – looking

explicitly at evidence on variation and inequalities - in answering questions about effect and effectiveness:

• Intervention: aims & objectives, delivery mode, intervener • Target group characteristics & views• Setting & context• Intensity/duration • Cost • Implementation & feasibility

Drafting recommendations

• Advisory committees draft the guidance

This is prepared on the basis of the best available evidence

Drafting the recommendations

• Recommendations– strength and applicability of evidence– cost effectiveness– impact, including on inequalities in health– risks, benefits– implementability

Generating and synthesising evidence - issues so far……….

Searching for evidence

• The need for comprehensive assessment for available evidence versus ‘forensic searching’ for most appropriate evidence.

• Lack of emphasis on ‘how things work’.

• Lack of match between our research questions and strategies for finding most appropriate studies.

On inequalities - a limited evidence base

• Evidence about what works to reduce inequalities very limited

• About 0.4% of published scientific papers discuss interventions which might reduce inequalities

• About the same percentage of funded research concerned with interventions

• Rich in description, weak on solution.

And why?

• Gaps in the initial formulation of primary research studies.

• Gap between evidence and practice

• Failure to distinguish between determinants of health and determinants of inequalities in health

The classification system

• The conceptual and operational apparatus for capturing different dimensions of inequalities is underdeveloped.

• The precise nature of the causal pathways and the different dimensions of inequality is under-investigated

• The health interaction between different aspects of inequalities not highly developed.

• The ways in which interventions work in different segments of the population not well understood

We need to move towards better conceptual frameworks for ….

• Helping to identify the causal models which operate from the social to the biological

• Need to distinguish proximal, intermediate and distal causes

• Need to establish necessary and sufficient conditions

• Need to establish biological and social plausibility

How can the review process help

• Getting the questions right

• Achieving methodological diversity

• Maintaining the need for quality

Getting the questions right – understanding the problem – primary research

• Placing questions in policy context - distinction between health disadvantages, health gaps and health gradients

• Make explicit models used to explain inequities in health and help us to understand the mechanisms by which health inequities are generated.

• Make better use of life course approach for understanding relationship between different interventions

Getting the questions right – review stage

• Distinguishing between impact, process and experience

• Distinguishing between audience, high level policy makers or local providers of services.

Achieving methodological diversity

• Internal to systematic review process – Starting further down the chain - more focus on the how things

work rather than what works?– Synthesising qualitative and quantitative – Synthesising impact, process and experience

• External to systematic review process– Different forms of knowledge – Whitehead’s ‘Evidence Jigsaw’.– Dealing with issues of transferability and plausibility of proposed

actions– Dealing with tacit knowledge of stakeholders – professionals and

the public

Maintaining the need for quality - assessment• Transparency, systematicity, relevance

• New tools for assessing strength of evidence

Also:• Importance of the outcomes – burden of ill health• Equity versus health impact• Risks of not taking action

How much should and can the review process help in

addressing these issues?

www.nice.org.uk