Variable breakdown

fev1_second_x100

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Section and category

Physical Exam.Lung function

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Description

“Second FEV1 measurement”

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Additional information

	Metadata
validation	Soft min: 40 or (Fev1_first_x100 - 100), Soft max: 550 or (Fev1_first_x100 + 100), Hard min: 10 or (Fev1_first_x100 - 200), Hard max: 700 or (Fev1_first_x100 + 200)
contents	No. of litres (x100)
is_mandatory	No

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Data summary

Baseline

mean	sd	min	q1	med	q3	max	mad	iqr	cv	skewness	se.skewness	kurtosis	n.valid	pct.valid
223.63	66.56	10	178	219	265	551	63.75	87	0.3	0.28	0	0.11	515413	100

Qc

mean	sd	min	q1	med	q3	max	mad	iqr	cv	skewness	se.skewness	kurtosis	n.valid	pct.valid
224.22	64.28	28	182	220	264	556	60.79	82	0.29	0.27	0.02	0.27	15816	100

Resurvey 1

mean	sd	min	q1	med	q3	max	mad	iqr	cv	skewness	se.skewness	kurtosis	n.valid	pct.valid
220.87	74.69	10	171	217	267	617	71.16	96	0.34	0.33	0.02	0.32	19481	98.37

Resurvey 2

mean	sd	min	q1	med	q3	max	mad	iqr	cv	skewness	se.skewness	kurtosis	n.valid	pct.valid
213.85	74.46	12	164	209	258	700	69.68	94	0.35	0.51	0.02	0.86	24300	96.23

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Between-survey agreement

[1] “Spearman’s correlation matrix:”

	Baseline	Qc	Resurvey1	Resurvey2
Baseline	1.000	0.885	0.759	0.731
Qc	0.885	1.000	0.730	0.725
Resurvey1	0.759	0.730	1.000	0.713
Resurvey2	0.731	0.725	0.713	1.000

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International Coordinating Centre, China Kadoorie Biobank (CKB), CTSU, Nuffield Department of Population Health, University of Oxford Old Road Campus, Headington, Oxford, OX3 7LF

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Copyright China Kadoorie Biobank (CKB), University of Oxford, (2024)

Page generated: 27-02-2024