Table 2.

Characteristics of included studies

First author, year	Study type	Number of patients (women)	US/CT	Aortic diameter measured	Frequency of follow-up	Cardiovascular risks	Length of follow-up (enrolment dates)	Method of growth rate estimating and reporting	Baseline AAA/cm	Growth rates cm/year
Li, J., 2008	Obs R	78 (3)	US	Maximal external cross-sectional in any plane	Once a year	Hypertension (n = 57) DM (n = 18) CHD (n = 62) MI (n = 32) Hypercholesterolemia (n = 44) Smoking (n = 52)	1~25 years, mean 7.9 ± 5.5 years (1975–2007)	Not reported; x ± sd	Overall: 2.1–5.7 (n = 64), [Growth rate only calculated for 64 patients	0.18 ± 0.23
									2.1–2.9 (n = 27)	0.13 ± 0.16
									3.0–4.9 (n = 30)	0.09 ± 0.07
									≧5.0 (n = 14)	0.46 ± 0.33
Wu, Q., 2009	Obs R	66 (4)	US	Maximal external cross-sectional in any plane	unclear	Hypertension (n = 66) DM (n = 28) CHD (n = 62) Hyperglycemia (n = 61) Peripheral atherosclerosis (n = 63) CI (n = 30) Smoking (n = 62)	11 years maximum (1997–2008)	Not reported; x ± sd	Overall:3.0–9.2 (n = 66)	0.75 ± 0.34
									3.0~4.9 (n = 31)	0.45 ± 0.24
									≧5.0 cm (n = 35)	1.02 ± 0.10
Zhang, L.F., 2006	Obs P	37 (4)	US	Maximal external cross-sectional in any plane	unclear	Hypertension (n = 21) CHD (n = 17) DM (n = 7) CI (n = 11) CRF (n = 3) PHD (n = 3) Other (n = 9)	0.5~11 years, mean 6.1 (unclear)	Not reported; x ± sd	Overall:3.0–8.9 (n = 37)	X = 0.38 ± 0.26
									3.0~3.9 (n = 14)	0.23 ± 0.11
									4.0~5.9 (n = 15)	0.37 ± 0.24
									6.0~8.9 (n = 8)	0.67 ± 0.29
Song, H.G., 2013	Obs R	57 (25)	US	Maximal external cross-sectional in any plane	Unclear	Unclear	1~8 years, mean 4.1 ± 1.6 years (unclear)	Not reported;x ± sd	Overall: unclear (n = 57)	0.40 ± 0.22
									3.0–3.9 (n = 21)	0.21 ± 0.05
									4.00~5.9 (n = 22)	0.38 ± 0.13
									> 6.0 (n = 14)	0.71 ± 0.14

Abbreviations: Obs observational study, P prospective study, R retrospective study, US ultrasonography, CT computed tomography