Bayesian Statistics Vague, variable, subjective to boot…

…and, when used as a basis for decision modelling, helpful for decision makers in NICE technology appraisals Dr Carole Longson Appraisal Programme Director

Attributes of Technology Appraisal Independent advisory committee formulates guidance Transparent and inclusive process Consultation with diverse groups All groups invited to submit evidence

Attributes of Technology Appraisal ‘Inclusive’ evidence base, not just clinical trials Multiple perspectives are often conflicting Decisions are made in the ‘real world’  lack of evidence or conflicting evidence  conflicting views of the same evidence  uncertainty

Evidence Research Evidence Patient Experience Clinical Practice

What matters? Need Size of effect Value of effect Service impact

The Appraisal Challenge Balance the evidence from different inputs Make robust decisions with less than perfect information Ensure process is transparent and decisions are justifiable

Independent technology assessment Patients and carers views and preferences Health professionals opinion Modelling the unknown Manufacturers data Balancing the Evidence

Why we need decision analytic models Uncertainty is the norm in technology appraisal! Good models help decision makers deal with complex and sometimes conflicting evidence

Why we need decision analytic models? To model or not to model?  Yes, no choice for many appraisals Decision analytic models help make better decisions at time t in the absence of perfect information  This is just what the appraisal process needs

Modelling Techniques and Decision Making ‘The good, the bad, the useful and the not so useful ’ We get them all in technology appraisals

"There is nothing more difficult to plan, more doubtful of success, nor more dangerous to manage, than the creation of a new system. For the initiator has the enmity of all who would profit by the preservation of the old institutions, and merely lukewarm defenders in those who should gain by the new ones." Machiavelli The Appraisal Challenge What have we learnt?