01.12.2017 | Research article | Ausgabe 1/2017 Open Access

Parity and bladder cancer risk: a dose-response meta-analysis
- Zeitschrift:
- BMC Cancer > Ausgabe 1/2017
Electronic supplementary material
Background
Methods
Literature search and eligibility criteria
Data extraction and quality assessment
Statistical analysis
Results
Study characteristics and quality assessment
Author, year
|
Design, study name
|
Country, study period
|
Study quality
a
|
Age
|
Cases; participants/controls
|
Parity
|
OR (95% CI)
|
Adjustment factors
|
---|---|---|---|---|---|---|---|---|
Cantor et al. 1992 [
20]
|
Case-control study
|
USA, 1986–1989
|
5
|
40–85
|
315; 821
|
1
|
Reference
|
Not reported
|
2
|
1.4 (0.8–2.4)
|
|||||||
3
|
1.6 (0.9–2.9)
|
|||||||
4
|
0.9 (0.5–1.8)
|
|||||||
5+
|
1.5 (0.8–2.7)
|
|||||||
La Vecchia et al. 1993 [
21]
|
Case-control study
|
Italy, 1983–1992
|
6
|
Case: blow 70; Control: 58 (median)
|
68; 5619
|
0
|
Reference
|
Age, education, parity, number of abortions, oral contraceptive and other female hormone use
|
1
|
1.2
|
|||||||
2
|
1.0
|
|||||||
3
|
0.8
|
|||||||
≥4
|
0.7
|
|||||||
Pelucchi et al. 2002 [
10]
|
Case-control study
|
Italy, 1985–1992
|
6
|
Case: 30–79 Control: 26–79
|
110; 289
|
0–1
|
Reference
|
Age, study center, education, BMI, cigarette smoking, and coffee and alcohol consumption
|
2–3
|
0.83 (0.47–1.45)
|
|||||||
≥4
|
0.88(0.41–1.90)
|
|||||||
Cantwell et al. 2006 [
8]
|
Cohort study
|
USA, 1980–1998
|
7
|
Case: 55.4 ± 8.8 Participants: 70.6 ± 8.4,
|
167; 54308
|
0
|
Reference
|
Age, calendar year and smoking status (never, former or current).
|
1
|
0.65 (0.36–1.18)
|
|||||||
2
|
0.96 (0,61–1,。50)
|
|||||||
3
|
0.82 (0.5–1.34)
|
|||||||
>4
|
0.75 (0.45–1.25)
|
|||||||
McGrath et al. 2006 [
11]
|
Cohort study, US Nurses’ Health Study
|
USA, 1976–2002
|
7
|
30–55
|
336; 116598
|
0
|
Reference
|
Age (months), time period (2-year questionnaire period), smoking status (never, former, current) and pack-years of smoking (continuous), and body mass index
|
1–2
|
0.85 (0.56–1.28)
|
|||||||
3–4
|
0.70 (0.47–1.05)
|
|||||||
≥4
|
0.84 (0.54–1.32)
|
|||||||
Prizment et al. 2006 [
22]
|
Cohort study, The Iowa Women’s Health Study
|
USA, 1986–2003
|
7
|
55–69
|
192; 37459
|
0
|
Reference
|
Age, smoking status and pack-years
|
1–2
|
0.81 (0.50–1.32)
|
|||||||
3–4
|
0.79 (0.48–1.27)
|
|||||||
≥5
|
0.79 (0.46–1.37)
|
|||||||
Huang et al. 2009 [
7]
|
Case-control study
|
Spanish, 1998–2001
|
6
|
Median: case 67.4
|
152; 166
|
0
|
Reference
|
Age, smoking status, and high-risk occupation
|
Control:67.8
|
≥1
|
0.43 (0.2–0.9)
|
||||||
Davis-Dao et al. 2011 [
13]
|
USA and China,
|
6
|
LAS:25–64;
|
LAS:349/349
|
LA:1
|
LA: Reference
|
LASBCS: smoking status in the reference year (current, former, never), pack-years of smoking, and BMI; CTS: race/ethnicity, smoking status and BMI.
|
|
Los Angeles Bladder Cancer Study (LAS): Case-control study;
|
Los Angeles: 1987–1996;
|
SHS:25–74;
|
SHS: 131/138
|
2
|
0.41 (0.98–0.87)
|
|||
CTS: not reported
|
CTS: 196/120857
|
3
|
0.63 (0.29–1.34)
|
|||||
≥4
|
0.70 (0.35–1.39)
|
|||||||
Shanghai Bladder Cancer Study (SHS): Case-control study
|
Shanghai:1995–1998;
|
SH: 1
|
SH: reference
|
|||||
2
|
0.63 (0.23–1.74)
|
|||||||
3
|
0.47 (0.16–1.33)
|
|||||||
California Teachers Study(CTS): Cohort study
|
CTS:1995–2005
|
≥4
|
0.56 (0.21–1.48)
|
|||||
CTS:1
|
CTS: reference
|
|||||||
2
|
1.14 (0.71–1.86)
|
|||||||
3
|
0.73 (0.42–1.27)
|
|||||||
≥4
|
1.06 (0.61–1.87)
|
|||||||
Dietrich et al. 2011 [
12]
|
Case-control study
|
USA, 1994–2001; 1993
|
6
|
25–74
|
207/403
|
0
|
Reference
|
Age and smoking status
|
July; 1995–1997
|
1–2
|
0.67 (0.36–1.24)
|
||||||
3–4
|
0.75 (0.40–1.39)
|
|||||||
≥5
|
0.74 (0.35–1.57)
|
|||||||
Daugherty et al. 2013 [
23]
|
Cohort study, NIH-AARP Diet and Health Study
|
USA, 1995–2006
|
7
|
50–71
|
651/201492
|
0
|
Reference
|
Age
|
1
|
0.78 (0.58–1.07)
|
|||||||
2
|
0.72 (0.56–0.92)
|
|||||||
3–4
|
0.78 (0.62–0.98)
|
|||||||
5+
|
0.73 (0.54–0.98)
|
|||||||
Kabat et al. 2013 [
24]
|
Cohort study, Women’s Health Initiative
|
USA, 1993–1998
|
6
|
50–79
|
480/145048
|
0
|
Reference
|
Age, education, pack-years, alcohol intake, parity, oral contraceptive use (ever, never)
|
1–2
|
0.71 (0.53–0.96)
|
|||||||
3–4
|
0.84 (0.63–1.12)
|
|||||||
≥5
|
0.72 (0.51–1.03)
|
|||||||
Weibull et al. 2013 [
6]
|
Cohort study
|
Sweden, 1964–2009, Median follow-up time:16.6 years
|
7
|
40~
|
2860/2009811
|
1
|
Reference
|
Age, highest educational level, and chronic obstructive lung disease.
|
2
|
0.85 (0.77–0.95)
|
|||||||
≥3
|
0.76 (0.68–0.86)
|
Ever versus never parity
Differences with parity number
No. of reports
|
RR (95% CI)
|
I
2 (%)
|
P value
|
|
---|---|---|---|---|
Overall
|
13
|
0.76 (0.70–0.82)
|
0
|
0.795
|
Number of parity
|
||||
1 ~ 2 vs. 0
|
7
|
0.82 (0.71–0.94)
|
17.7
|
0.295
|
3 ~ 4 vs. 0
|
7
|
0.79 (0.68–0.91)
|
0
|
0.997
|
≥ 5 vs. 0
|
6
|
0.76 (0.66–0.88)
|
0
|
0.994
|
Subgroup analysis
|
||||
Study design
|
||||
Cohort study
|
6
|
0.77 (0.71–0.84)
|
0
|
0.802
|
Case-control study
|
7
|
0.71 (0.60–0.83)
|
0
|
0.598
|
Number of cases
|
||||
< 250
|
7
|
0.68 (0.56–0.81)
|
0
|
0.673
|
> 250
|
6
|
0.78 (0.71–0.84)
|
0
|
0.841
|
Location
|
||||
USA
|
9
|
0.72 (0.65–0.81)
|
0
|
0.989
|
Others
|
4
|
0.79 (0.71–0.87)
|
39.7
|
0.174
|
Smoking
|
||||
Never smoking
|
5
|
0.47 (0.35–0.63)
|
0
|
0.562
|
Ever smoking
|
4
|
0.90 (0.67–1.21)
|
0
|
0.531
|
Adjustment for smoking
|
||||
Yes
|
8
|
0.67 (0.57–0.79)
|
0
|
0.815
|
No
|
5
|
0.79 (0.72–0.86)
|
0
|
0.882
|
Adjustment for age
|
||||
Yes
|
9
|
0.77 (0.71–0.84)
|
0
|
0.850
|
No
|
4
|
0.65 (0.52–0.81)
|
0
|
0.684
|
Adjustment for BMI
|
||||
Yes
|
5
|
0.66 (0.53–0.81)
|
0
|
0.469
|
No
|
8
|
0.76 (0.70–0.82)
|
0
|
0.952
|