1. Comparing the multiple sources of cancer treatment data
No acronym for the title yet
Sean McPhail, Sam Johnson, Daniela Tataru, Margreet Lüchtenborg, Sally Vernon, Michael Peake
(and thanks to James Thomas)

2. Background
We are reasonably good at counting tumours, mortality, and calculating survival. Historically we have been less good at counting treatments. Is that still true?
Comparing the multiple sources of cancer treatment data

3. Treatment Treatment Surgery Radiotherapy (RT) Chemotherapy (CT)
Comparing the multiple sources of cancer treatment

4. 5 Treatment data sources
Inpatient Hospital Episode Statistics: HES
Cancer Waiting Times: CWT
Radio-therapy Data Set: RTDS
Systematic Anti-Cancer Therapy: SACT
Cancer Registration
Comparing the multiple sources of cancer treatment data

5. Motivation
Can we measure the fraction of patients are treated with each modality in each of these datasets?
Are these sources consistent with one another?
Can we use the most complete of these sources, or a combination, to assess the overall level of cancer treatment?
Comparing the multiple sources of cancer treatment data

6. Methods
Look at - Invasive tumours excluding non-melanoma skin Persons diagnosed to Treatment in -30 to +182 days of diagnosis Concentrate on – Fact of treatment Trust of first treatment Date of first treatment
Comparing the multiple sources of cancer treatment data

7. The group of tumours under discussion
143,132 tumours in 6 months. 43,073 CTs. 30,927 RTs.
Comparing the multiple sources of cancer treatment data

8. Linking these tumours to treatments
Comparing the multiple sources of cancer treatment data

9. Fraction of tumours treated by CT and RT
Registry
CT: 24.8% RT: 18.3%
Hospital Episode Statistics
CT: 22.4% RT: 3.4%
Cancer Waiting Times
CT: 22.9% RT: 18.6%
Systematic Anti-Cancer Therapy / RadioTherapy DataSet
CT: 21.4% RT: 20.2%
All of the above…
CT: 30.1% (43,073) RT: 21.6% (30,927)
Comparing the multiple sources of cancer treatment data

10. Dividing up a dataset with Venn Diagrams
Of the people in this room how many have been to London and/or Dublin this year?
London
Dublin 30 20 20
Comparing the multiple sources of cancer treatment data

11. 2-way and 3-way Venn Diagrams
Comparing the multiple sources of cancer treatment data

12. Distribution of 43,073 chemotherapies
HES
CWT
Registry
SACT
Comparing the multiple sources of cancer treatment data

13. Distribution of 43,073 chemotherapies
HES
CWT
Registry
SACT 3% 2% 1% 4% 1%
11% 4% 4% 4%
43% 4% 2%
10% 6% 1%
Comparing the multiple sources of cancer treatment data

14. Are chemotherapy datasets consistent?
Trust Matches Date Matches (exact)
Results
Implications
Comparing the multiple sources of cancer treatment data

15. Are chemotherapy datasets consistent?
Trust Matches Date Matches (30 day)
Results
Implications
Comparing the multiple sources of cancer treatment data

16. Distribution of 30,927 Radiotherapies
HES
CWT
Registry
RTDS
Comparing the multiple sources of cancer treatment data

17. Distribution of 30,927 Radiotherapies
HES
CWT
Registry
RTDS 1% 1% 0% 1%
11% 0% 1% 2% 5%
11% 1% 1%
61% 1% 3%
Comparing the multiple sources of cancer treatment data

18. Are radiotherapy datasets consistent?
Trust Matches Date Matches (exact)
Results
Implications
Comparing the multiple sources of cancer treatment data

19. Are radiotherapy datasets consistent?
Trust Matches Date Matches (30 day)
Results
Implications
Comparing the multiple sources of cancer treatment data

20. The overall level of cancer treatment?
If data sources were independent…
… and capture of treatment data was also at random…
… then flattening of cumulative completeness would imply complete data.
But… registry feeds from CWT & HES
systematic effects (e.g. private care, primary chemo, local issues, other reasons…)
Comparing the multiple sources of cancer treatment data

21. But, what datasets do we believe?
Combining all sources:
CT: 30.1% RT: 21.6%
Insist on dual source confirmation:
CT: 26.4% RT: 19.7%
Accept single source Registry, SACT/RTDS. Only accept HES with CWT:
CT: 28.7% RT: 21.3%
Lazy solution: Registry and SACT/RTDS only:
CT: 28.2% RT: 21.3%
Comparing the multiple sources of cancer treatment data

22. Summary
Can we measure completeness in each? Yes Are they consistent? Yes Good agreement between both trust of diagnosis and treatment period (except RT for HES) – we appear to be matching clinical treatments. Can we define an overall cohort? Yes (-ish) CT nearly 30%, RT just over 20% We think we have eliminated much of the “random” missing data – “systematically” missing data may still be missing. Some clinical input and additional work to finalise definitions.
Comparing the multiple sources of cancer treatment data

23. Thank you for listening!
Background
Methods
Results
Implications
Comparing the multiple sources of cancer treatment