HTA Training - Prof Cathal Walsh - March 27th 2015

Intro to Health

Technology

Assessment

Cathal Walsh

Centre for Health Decision Science (HRB)

@CHeDS_ie

Biostatistician (NCPE) - Chair of Statistics (UL)

Decision Making

Question

Information Values

A set of

recommended

treatments

Health Technology

Assessment

• In theory, HTA provides a structured

framework for decision making.

• The framework used in Ireland is similar

to that employed in the UK and uses the

QALY and cost tradeoff.

Decision Making … the QALY

• The quality adjusted life year (QALY) is a

function of quality and duration of life.

This is best illustrated by a sketch …

• Note that it explicitly trades side effects,

disability and inconvenience of treatment

(etc!) against outcomes.

Tx 1 (Sustained)

Tx 2 (+efficacy, waning.)

Notes on the QALY

• In theory we can compare in an

equitable fashion across disease areas.

• This allows consideration of the impact

of interventions in a fair way and in a

univariate fashion.

• Thus a perfect ranking of interventions

can be obtained.

Decision Making - the C/E

plane

• The cost effectiveness plane is a core

aspect of how outcomes are

communicated and interpreted. It trades

off gains in health outcomes (on the x-

axis) and costs (on the y-axis).

Simple Decisions ... ?

*

++ Health

++ Investment

***

Simple Decisions ... ?

(Q,C) Do It

++ Health

++ Investment

Simple Decisions ... ?

(Q,C)

Don’t do It

Simple Decisions ... ?

(Q,C)

Put it on the

list of things to

do …

Simple Decisions ... ?

(Q,C)

Put it on the

list of things to

do …

ICER

Simple Decisions ... ?

Simple Decisions ... ?

Simple Decisions ... ?

Simple Decisions ... ?

Simple Decisions ... ?

*

++ Health

++ Investment

***

The Threshold … The Theory

ICER < 45k / Q good

ICER > 45k / Q bad

Simple Decisions ... ?

*

++ Health

++ Investment

***

The Threshold … The Theory

BUT … why use 45k?

The Threshold … The Theory

Utilisation

Pro

sp

ective

Th

resh

old

The Threshold … The Theory

Utilisation

Pro

sp

ective

Th

resh

old

The Threshold … Estimation in Practice

• What is the cost per QALY of the things

we stop doing to afford the new things?

• What is the cost per QALY of the things

we should stop doing to afford the new

things?

• On average, what is the marginal cost

per QALY in our health system?

The Threshold … Estimation in Practice

• What is the cost per QALY of the things

we stop doing to afford the new things?

• What is the cost per QALY of the things

we should stop doing to afford the new

things?

• On average, what is the marginal cost

per QALY in our health system?

Inefficiencies

Disinvestment

Practical Assessment

(Data?!)

Other considerations

• The Value set we use.

• The Uncertainty associated with the

parameters.

• The comparators used in the models.

• Indications for treatment.

• Structural uncertainty in models.

• Societal vs healthcare payer perspective.

Workarounds (Fudges)

• QALY loadings.

• Disease specific threshold.

• Selective alternative perspectives.

• Ring fenced budgets for selected

conditions.

• Differential discounting.

• MCDA (perhaps?).

Multi Criteria Decision

Analysis

• Affects the Value side alone.

• Allows explicit incorporation of other

factors into the value function.

• Strictly speaking cost per QALY is a form

of MCDA.

• Cannot change the budget available –

just the ordering of the interventions we

fund.

What do we do now?

• An ‘informal’ MCDA approach.

• A 45,000 / QALY ‘initial’ threshold.

• Reimbursement occurs for some

interventions above this level.

• A process for broader consideration of

the decision exists.

Exercise