Table 1.

Coding for CKD by patient characteristics among those with biochemical evidence of CKD

	n with biochemical CKD at round 1	% of these who are coded for CKD	Univariable OR for coding (95% CI)	Multivariablea OR for coding (95% CI)
Sex
Female	152 194	68.8	1	1
Male	104 239	70.6	1.09 (1.06–1.11)	1.04 (1.02–1.07)
Age (years)
<50	5371	57.7	0.82 (0.77–0.87)	0.82 (0.78–0.88)
50–59	12 612	55.9	0.79 (0.76–0.82)	0.86 (0.83–0.89)
60–69	39 520	62.1	1	1
70–79	82 776	69.7	1.38 (1.34–1.42)	1.23 (1.20–1.27)
80–89	90 209	73.9	1.69 (1.64–1.75)	1.37 (1.32–1.41)
≥90	25 945	74.2	1.72 (1.64–1.80)	1.34 (1.28–1.40)
IMDb
<10 000	41 051	71.4	1	1
10 000–14 999	28 079	71.2	0.98 (0.95–1.02)	1.00 (0.97–1.04)
15 000–19 999	30 222	70.4	0.95 (0.92–0.99)	0.98 (0.94–1.02)
20 000–24 999	31 815	70.1	0.94 (0.91–0.97)	0.99 (0.95–1.02)
≥25 000	40 230	70.1	0.95 (0.91–0.99)	1.01 (0.97–1.05)
Missing	85 036	67.2	0.86 (0.78–0.95)	1.09 (0.96–1.23)
Last known CKD stagec
Stage 3a	160 100	60.8	1	1
Stage 3b	75 855	82.5	3.01 (2.90–3.12)	2.71 (2.62–2.80)
Stage 4	17 224	89.7	5.64 (5.25–6.06)	5.03 (4.70–5.38)
Stage 5	3254	90.3	5.94 (5.22–6.77)	5.81 (5.13–6.58)
Diabetes
No	187 716	67.5	1	1
Yes	68 717	75.2	1.45 (1.41–1.49)	1.11 (1.08–1.14)
Hypertension
No	74 817	59.2	1	1
Yes	181 616	73.8	1.83 (1.79–1.87)	1.50 (1.47–1.53)
Statin offered
No	84 885	62.0	1	1
Yes	171 548	73.3	1.64 (1.60–1.67)	1.38 (1.35–1.40)
Country
Wales	85 308	67.1	1	1
England	171 125	70.7	1.25 (1.12–1.40)	1.42 (1.18–1.71)

^aSimultaneous adjustment for all characteristics in the table.

^bLow IMD rank corresponds to higher deprivation.

^cBased on last eGFR measurement. Stage 3a: eGFR 46–59 mL/min/1.73 m²; Stage 3b: eGFR 31–45 mL/min/1.73 m²; Stage 4: eGFR 16–30 mL/min/1.73 m²; Stage 5: eGFR <15 mL/min/1.73 m².