Table 3.

Recording of Breast Cancer Diagnosis, Treatments, and Supporting Clinical Codes During Follow-Up in CPRD Aurum and CPRD GOLD

Breast Cancer Data Elementa	CPRD AurumN=131,936 (%)	CPRD GOLDN=69,102 (%)
Breast cancer diagnosis	120,084 (91.0)	62,877 (91.0)
Mean number codes ± st. dev.	5.8 ± 11.9	1.3 ± 1.0
Median (IQR)	2 (1–5)	1 (1–1)
Mastectomy	38,459 (29.2)	19,853 (28.7)
Mean number codes ± st. dev.	1.6 ± 2.2	1.1 ± 0.4
Median (IQR)	1 (1–2)	1 (1–1)
Lumpectomy	43,581 (33.0)	20,001 (28.9)
Mean number codes ± st. dev.	1.4 ± 1.7	1.1 ± 0.4
Median (IQR)	1 (1–1)	1 (1–1)
Breast cancer drug prescription	97,130 (73.6)	51,272 (74.2)
Mean number codes ± st. dev.	39.6 ± 35.7	31.9 ± 28.8
Median (IQR)	32 (17–55)	26 (11–44)
Radiation	26,044 (19.7)	7967 (11.5)
Mean number codes ± st. dev.	1.3 ± 0.7	1.1 ± 0.4
Median (IQR)	1 (1–1)	1 (1–1)
Chemotherapy	18,496 (14.0)	9301 (13.5)
Mean number codes ± st. dev.	2.2 ± 2.9	1.8 ± 2.0
Median (IQR)	1 (1–2)	1 (1–2)
Suspected breast cancer	24,800 (18.8)	4201 (6.1)
Mean number codes ± st. dev.	1.3 ± 1.3	1.1 ± 0.3
Median (IQR)	1 (1–1)	1 (1–1)
Lump symptom	58,434 (44.3)	30,799 (44.6)
Mean number codes ± st. dev.	1.6 ± 2.2	1.4 ± 0.9
Median (IQR)	1 (1–2)	1 (1–2)
Breast cancer biopsy	17,117 (13.0)	8913 (12.9)
Mean number codes ± st. dev.	1.2 ± 0.9	1.1 ± 0.4
Median (IQR)	1 (1–1)	1 (1–1)
Cancer care	109,088 (82.7)	54,670 (79.1)
Mean number codes ± st. dev.	2.1 ± 2.8	2.1 ± 2.9
Median (IQR)	1 (1–2)	1 (1–2)
Referral or visit to specialist	107,368 (81.4)	47,410 (68.6)
Mean number codes ± st. dev.	9.7 ± 9.5	9.1 ± 8.8
Median (IQR)	7 (3–13)	7 (3–12)
Palliative care	14,791 (11.2)	6876 (10.0)
Mean number codes ± st. dev.	3.7 ± 5.7	3.2 ± 4.6
Median (IQR)	2 (1–4)	1 (1–3)

Note: ^aNumber of codes restricted to 1 per date among patients with at least one code.

Abbreviations: IQR, Interquartile range; st.dev, Standard Deviation.