Table 3

Associations between asthma deaths and PEF and FEV₁ monitoring in primary and secondary care in cases (n = 532) and controls (n = 532)

	3 months before index date				4–12 months before index date				1+ to 5 years before index date
	Cases	Controls	Odds ratio	95% CI	Cases	Controls	Odds ratio	95% CI	Cases	Controls	Odds ratio	95% CI
Data presented as percentages.
Odds ratios from conditional logistic regression are adjusted for sex.
p<0.05, p<0.01, **p<0.001 (trend).
Primary care
No of occasions PEF recorded				***				*
0	77.8	63.2	1.00	–	60.3	54.9	1.00	–	32.9	27.4	1.00	–
1–5	22.0	34.8	0.50	0.38 to 0.67	34.4	37.4	0.83	0.64 to 1.07	39.1	41.2	0.78	0.58 to 1.06
6–10	0.2	1.9	0.09	0.01 to 0.70	4.1	6.4	0.59	0.34 to 1.02	13.9	15.2	0.75	0.51 to 1.11
10+	0	0.2			1.1	1.3	0.78	0.26 to 2.33	14.1	16.2	0.70	0.46 to 1.04
No of occasions FEV₁ recorded
0	99.6	99.1	1.00	–	99.1	99.2	1.00	–	98.5	98.3	1.00	–
1–5	0.4	0.9	0.41	0.08 to 2.10	0.9	0.8	1.23	0.33 to 4.59	1.5	1.7	0.90	0.35 to 2.32

Secondary care
No of occasions PEF recorded in outpatients/discharge letters
0	88.0	85.9	1.00	–	78.9	73.5	1.00	–	58.1	58.1	1.00	–
1–5	12.0	14.1	0.82	0.57 to 1.19	19.9	24.8	0.75	0.56 to 1.00	28.6	28.8	0.99	0.75 to 1.31
6–10	0	0			1.1	1.3	0.83	0.28 to 2.47	7.5	7.7	0.96	0.61 to 1.52
10+	0	0			0	0.4			5.8	5.5	1.09	0.63 to 1.91
No of occasions FEV₁ recorded
0	95.1	94.4	1.00	–	88.5	88.2	1.00	–	75.8	75.2	1.00	–
1–5	4.9	5.6	0.87	0.50 to 1.50	11.5	11.8	0.97	0.66 to 1.43	19.0	21.2	0.90	0.66 to 1.23
6+	0	0							5.3	3.6	1.46	0.80 to 2.65