Cost-effectiveness of an early awareness campaign for colorectal cancer

Sophie Whyte 1, Sue Harnan 1, Paul Tappenden 1, Mark Sculpher 2, Seb Hinde 2, Claire Mckenna 2

Policy Research Unit in Economic Evaluation of Health and Care Intervention (EEPRU)

1 School of Health and Related Research (ScHARR), University of Sheffield

2 Centre for Health Economics, University of York

Contact: Sophie.Whyte@sheffield.ac.uk

Early awareness campaigns

• The primary aim of cancer awareness campaigns is earlier presentation of symptomatic cancers through improved public knowledge of the symptoms

Data from early awareness campaigns

Data from the pilot early awareness campaign for colorectal cancer showed an increase in GP referrals for a short period following the campaign.

Awareness campaign efficacy

Key questions:• Does this data mean the campaign

‘worked’?• Should it be repeated?

To understand benefit of campaign need information on longer-term outcomes such as ‘change in cancer incidence or mortality’

• A campaign may also lead to increased numbers of GP attendances by the ‘worried well’

• Some critics assert that the campaigns will ‘undo years of work persuading patients with minor ailments to stay at home’.

Project Aim

• Estimate cost effectiveness of an early awareness campaign using data from the colorectal cancer early awareness campaign piloted in the East of England and south west regions in January 2011.

• The estimates provide an improved understanding of the benefits of such a campaign so can be used to inform policy decisions.

Potential effects of an early awareness campaign for colorectal cancer

Public awareness of signs and symptoms Increase in awareness?

Early Awareness campaign TV, radio, press, online, etc.

GP consultations Increase?

GP referrals for suspected CRC Increase?

Cancer diagnoses Change in incidence/stage distribution?

Diagnosis of other lower GI conditions Increase?

Cancer mortality Decrease?

CRC screening Increase in uptake?

lives saved

treatment costs

consultation costs

campaign costs

referral costs

screening costs

Scope of analysis

The analysis captures:• the direct costs of the campaign, • the costs any additional GP

consultations/appointments in secondary care resulting from the campaign

• benefits of the campaign due to earlier diagnosis and any change in screening uptake.

Data from the pilot campaign used in the modelling

Data observed from pilot campaign

Base case assumption in model

Scenario analyses

GP attendances 700 increase over 3 month period (532 increase if diarrhoea included as a symptom) Equivalent to 60,000-80,000 nationally.

70,000 more attendances nationally over 3 month period

Assumed 50% ‘additional’& 50% ‘earlier’

Assumed 90% ‘additional’ & 10% ‘earlier’

GP referrals 1,956 increase in referrals over 5 month period (+28%)

17,519 additional referrals nationally

Assumed 50% ‘additional’& 50% ‘earlier’

Assumed 90% ‘additional’ & 10% ‘earlier’

CRC incidence 7-11% increase in incidence for 1 month

10% increase in presentation rates for 1 month

5-20% magnitude 1-6 month duration

CRC incidence stage distribution

Numbers too small to draw any conclusions

Campaign assumed to have the same proportional effect on presentation rates for each CRC stage.

Short term increase in incidence only consists of Dukes stages C & D

CRC screening uptake

No significant change which could be attributed to the campaign

Assume screening uptake unaffected by campaign

Exploratory analysis undertaken

Cost of running campaign

£5 million £5 million -

Methods• Pilot data demonstrates short term

impacts of the awareness campaign.• A mathematical model was used in

combination with the pilot data to predict long term impacts of the campaign on cancer incidence, mortality and costs.

• An existing mathematical model [1] was adapted (representing the CRC disease natural history, symptomatic presentation and the bowel cancer screening programme).

[1] Re-appraisal of the options for colorectal cancer screening in England; Whyte S, Chilcott J, Halloran S, (Colorectal Disease, March 2012)

CRC=colorectal cancer, LR=low risk, HR=high risk

Normal Epithelium

LR adenomas

HR adenomas

Dukes’ A CRC

Dukes’ B CRC

Dukes’ C CRC

Stage D CRC

Dead (CRC)

Dukes’ A CRC clinical

Dukes’ C CRC clinical

Stage D CRC clinical

Dukes’ B CRC clinical

Dead (non-CRC)

Transition estimated within model calibration

Transition estimated directly from mortality data

CRC natural history model CRC screening pathways

Invited to screening

Screening test completed

Do not attend screening

Do not attend follow up

No adenomas

Positive screening result – refer to follow up (colonoscopy)

Negative screening test result / LR adenomas found

Return to general screening population

LR adenomas

HR adenomas

CRC CRC treatment

Attend follow up

Surveillance (annual/ 3-yearly colonoscopy)

Model structure

Modelling methodology

• Four rates relating to symptomatic or chance presentation with Dukes’ A-D CRC. Baseline presentation rates reflect the England population from years 2004 to 2006 i.e. before screening commenced.

• The four transition probabilities are increased to result in an increase in incidence which matches the observed increase seen in the pilot campaign.

• Assumption: campaign causes a temporary change in the transition probabilities and that subsequently these probabilities will return to their pre-campaign values.

• No data available on stage distribution of incidence. -> Assume that the extra incidence due to the awareness campaign has the usual CRC stage distribution.

Results-Effectiveness

The campaign causes:­ Dukes’ stage A-C CRC presenting

symptomatically Stage D CRC presenting

symptomatically. ­ CRC presenting symptomatically. ¯ Screen/surveillance detected CRC¯ CRC specific deaths­ QALYs.

Results-Costs

Overall the campaign lead to increase in NHS costs

­ Campaign running cost¯ Screening costs (caused by a decrease in

positives at screening since more CRC presents symptomatically)

­ CRC treatment costs (1) CRC is presenting at younger ages which are

associated with higher treatment costs.

(2) A shift of cases from stage D to Dukes’ C and Dukes’ C CRC is associated with higher treatment costs than Dukes’ D.

­ Costs associated with increased GP consultations and referrals (account for only a small proportion of total costs and are considerably less than the cost of the campaign itself)

Model predictions

CRC incidence - symptomatic presentation Dukes Stage A 26B 52C 33D -92

CRC incidence - symptomatic presentation TOTAL 20CRC incidence screen/surveillance detected Dukes Stage A -0

B -1 C -2 D -2

CRC incidence - screening/surveillance detected TOTAL -5 CRC-specific deaths -66 Deaths with undiagnosed CRC -14 Total costs related to screening (discounted) 3,407-£ Cancer management (inc. pathology) costs (discounted) 94,443£ Cost of additional GP consultations/referrals (discounted) 855,716£ Cost of awareness campaign (discounted) 4,499,995£ Total cost (discounted) 5,446,745£ Total life years gained (discounted) 622 Total QALYs gained (discounted) 404 ICER 13,496£ NMB 2,624,770£

Model predictions for the current population of England evaluated over a lifetime: Change compared to 'No awareness campaign'

For a CRC awareness campaign resulting in a 10% increase in presentation rates for a period of one month

Modelling uncertainty in change in presentation rates due to campaign: duration and magnitude

0%

5%

10%

15%

20%

0 1 2 3 4 5 6

Increase in symptomatic

presentation rate (%)

Duration of increase in symptomatic presentation rate (months)

Number of CRC deaths prevented

800-900

700-800

600-700

500-600

400-500

300-400

200-300

100-200

0-100

base case= 66 deaths prevented

0.05

0.1

0.15

0.2

1 2 3 4 5 6

Increase in symptomatic presentation rate (%)

Duration of increase in symptomatic presentation rate (months)

ICER

25000-30000

20000-25000

15000-20000

10000-15000

5000-10000

0-5000

base case= ICER=£13K per QALY

Modelling uncertainty in change in presentation rates due to campaign: duration and magnitude

Priorities for future research

Co-ordinate and maximise the evaluation and dissemination of efforts that have already been made to increase cancer awareness.• comparison with non-intervention regions• clear reporting of completeness of data and potential

data limitations

Information of importance for future modelling studies:• duration of effect of campaign• effect of campaign on CRC incidence• effect of campaign on emergency presentation rates• effect of campaign by age• differential diagnoses costs associated with emergency

presentation versus two-week wait referrals • rates of diagnosis of other lower GI conditions with

similar symptoms to CRC.