Table 3.

Measurement description for the Middle Aged Danish Twins (MADT)

	N	Range	mean ± SD
MZ
PEF
1. Blow	1,291	55–840	365 ± 133
2. Blow	1,277	57–867	384 ± 133
3. Blow	1,244	64–930	387 ± 135
MaxPEF	1,342	64–930	404 ± 132
FEV1
1. Blow	1,315	0.46–4.91	2.70 ± 0.76
2. Blow	1,266	0.49–5.16	2.74 ± 0.76
3. Blow	1,222	0.49–5.18	2.76 ± 0.77
MaxFEV1	1,341	0.51–5.18	2.81 ± 0.76
FVC
1. Blow	1,311	0.70–6.43	3.35 ± 0.91
2. Blow	1,261	0.73–6.72	3.39 ± 0.90
3. Blow	1,220	0.73–6.35	3.41 ± 0.91
MaxFVC	1,329	0.80–6.72	3.50 ± 0.90
DZ
PEF
1. Blow	1,229	58–761	372 ± 131
2. Blow	1,189	76–772	392 ± 133
3. Blow	1,157	33–796	395 ± 135
MaxPEF	1,265	76–796	413 ± 132
FEV1
1. Blow	1,232	0.42–5.08	2.76 ± 0.79
2. Blow	1,186	0.50–5.07	2.80 ± 0.78
3. Blow	1,145	0.46–5.15	2.80 ± 0.79
MaxFEV1	1,261	0.50–5.15	2.88 ± 0.78
FVC
1. Blow	1,225	0.74–6.37	3.45 ± 0.95
2. Blow	1,180	0.81–6.68	3.47 ± 0.93
3. Blow	1,145	0.47–6.92	3.47 ± 0.94
MaxFVC	1,250	0.83–6.92	3.60 ± 0.94
DOS
PEF
1. Blow	1,287	48–792	364 ± 132
2. Blow	1,268	65–817	384 ± 134
3. Blow	1,236	66–844	386 ± 137
MaxPEF	1,324	66–844	406 ± 134
FEV1
1. Blow	1,290	0.40–5.29	2.71 ± 0.79
2. Blow	1,256	0.43–5.28	2.75 ± 0.78
3. Blow	1,218	0.46–5.14	2.77 ± 0.78
MaxFEV1	1,318	0.46–5.29	2.83 ± 0.78
FVC
1. Blow	1,289	0.52–6.92	3.39 ± 0.93
2. blow	1,244	0.47–6.71	3.41 ± 0.92
3. Blow	1,214	0.51–6.63	3.45 ± 0.92
MaxFVC	1,305	0.52–6.92	3.55 ± 0.92

N number of twins, PEF values measured in L/min, FEV₁ and FVC measured in L. Values are the range and mean ± SD for spirometric measurements of PEF, FEV₁, and FVC among monozygotic twins (MZ), dizygotic same-sex twins (DZ), and dizygotic opposite-sex twins (DOS)