Practical Issues in Implementation: Colorectal Cancer Case Study - PowerPoint PPT Presentation

Practical Issues in Implementation: Colorectal Cancer Case Study Miqdad Asaria 1

Case studies • Aim to use case studies to illustrate – Practical issues in implementation – Presentation of results to decision makers 2

Colorectal Cancer Screening • Differential impact of disease – Association between socio-economic deprivation and incidence of CRC • Differential impact of healthcare (i.e. screening) – Association between socio-economic deprivation and screening uptake – Screening for CRC reduces mortality • Tappenden et al evaluated population-based colorectal cancer screening programmes – Focus on biennial FOBT between ages 50-69 combined with follow up colonoscopy (our base case strategy) – Aim to adapt evaluation to estimate adjusted distribution 3

Data for Standard CEA • CRC incidence • CRC progression • CRC HRQoL • CRC mortality • Non-CRC mortality • CRC treatment costs • By strategy – Uptake of screening – Uptake of follow up colonoscopy – Screening costs 4

Additional for Framework Value judgements to distinguish unfair inequalities • – In this case inequalities associated with deprivation and ethnicity are deemed unfair • Parameters that vary by demographic variables of interest to calculate health gains and costs by group – Pilot studies gave odds ratio for screening/colonoscopy uptake by Gender, age, deprivation and ethnicity • – For other parameters such as mortality • IMD used for deprivation in other studies but selected ethnicity variable less common Population size and life expectancy by variables of interest to calculate health • levels – Covariance between ethnicity and IMD not reported • How to allocate opportunity costs of this programme – Assume equal across all users of NHS 5

Comparator Strategies • Hypothetical comparator policy – Social marketing to increase screening and follow up colonoscopy uptake – 100% uptake of both in all groups (max possible gain) – Arbitrary cost £100 million • Results by variables of interest in terms of expected – Level of health – Change in health 6

Unadjusted Bivariate IMD Total Health by Socio-Economic Group 0.0047 81 FOBT 80 FOBT+marketing 0.0072 79 QALYs 78 0.0082 77 76 0.0082 0.0091 75 74 Most IMD4 IMD3 IMD2 Least deprived deprived Socio-economic deprivation (IMD5) (IMD1) 7

Unadjusted Bivariate Ethnicity Total Health by Ethnicity Group 100 FOBT FOBT+marketing 0.0046 0.0066 80 60 QALYs 40 20 0 ISC1_4 ISC5 Ethnicity Groups 8

Adjusted Univariate (per person) Univariate Health Distribution 81 0.0048 0.0038 FOBT 80 FOBT + £100 million 79 0.0073 0.0069 marketing 78 QALYs 0.0083 0.0080 77 76 0.0083 0.0079 75 0.0092 0.0091 74 Lowest health level → Highest health level IMD5*ISC1_4 IMD5*ISC5 IMD4*ISC1_4 IMD4*ISC5 IMD3*ISC1_4 IMD3*ISC5 IMD2*ISC1_4 IMD2*ISC5 IMD1*ISC1_4 IMD1*ISC5 Population Groups (not equal size) 9

Treatment Effect (per person) 0.01 0.8 Health 0.009 FOBT 0.7 Colonoscopy 0.008 0.6 0.007 Screening uptake 0.5 0.006 0.005 0.4 QALYs 0.004 0.3 0.003 0.2 0.002 0.1 0.001 0 0 10

Discussion • Additional data – CEA limited by prior data collection and adjusted analyses – Easier to accommodate common socio-demographic variables – Covariance an issue in parameter estimation and population size • Small absolute differences – In health per person, in gradient and measures of inequality – Should results be presented per person or at population level? Further work to characterise uncertainty • – In parameter values – In value judgements In further case study work what should we aim to illustrate? • 11