Table 2

Meta-regression of the risk of all-cause dementia according to marital status, stratified by study time period, case ascertainment methodology, study type and study quality

Widowed versus marriedDivorced versus marriedLifelong single versus married
Stratified analysis:
Relative risk (95% CI)
Number of studies
Meta-regression coefficient (95% CI) p valueStratified analysis:
Relative risk (95% CI)
Number of studies
Meta-regression coefficient (95% CI) p-valueStratified analysis:
Relative risk (95% CI)
Number of studies
Meta-regression coefficient (95% CI) p value
Method of case ascertainmentClinical assessment1.20 (1.02 to 1.41)
n=9
b=−0.06 (−0.18 to 0.05) p=0.290.99 (0.71 to 1.37)
n=7
b=0.34 (0.06 to 0.62)
p=0.02
1.42 (1.07 to 1.90)
n=6
b=−0.27 (−0.55 to 0.01)
p=0.06
Clinical registers1.12 (1.07 to 1.18)
n=2
1.11 (0.52 to 2.38)
n=2
1.23 (1.17 to 1.29)
n=2
Study typeCohort1.10 (1.05 to 1.28)
n=7
b=0.28 (0.09 to 0.46)
p=0.004
1.16 (0.87 to 1.55)
n=6
b=−0.83 (−1.69 to 0.03)
p=0.06
1.24 (1.17 to 1.30)
n=5
b=0.08 (−0.45 to 0.62)
p=0.76
Case–control/cross-sectional1.39 (1.16 to 1.67)
n=4
0.55 (0.23 to 1.31)
n=3
1.21 (0.67 to 2.18)
n=3
Global quality scoreHigher quality ≥61.13 (1.02 to 1.31)
n=4
b=0.08 (-0.06 to 0.23)
p=0.27
1.16 (0.83 to 1.62)
n=4
b=−0.40 (-0.88 to 0.08)
p=0.10
1.26 (1.09 to 1.45)
n=3
b=0.20 (-0.17 to 0.57)
p=0.29
Lower quality <61.22 (0.96 to 1.54)
n=7
0.88 (0.54 to 1.44)
n=5
1.33 (0.92 to 1.92)
n=5
Increase in quality by one pointb=−0.04 (−0.08 to −0.002)
p=0.04
n=11
b=0.12 (0.01 to 0.24)
p=0.04
n=9
b=−0.05 (−0.13 to 0.03)
p=0.21
n=8
Time periodMean DoB before 19271.11 (0.93 to 1.31)
n=6
b=0.15 (−0.14 to 0.43)
p=0.32
0.98 (0.71 to 1.37)
n=6
b=0.35 (0.08 to 0.63)
p=0.01
1.40 (1.06 to 1.85)
n=5
b=−0.22 (−0.50 to 0.06)
p=0.13
Mean DoB after 19271.23 (1.06 to 1.43)
n=5
1.08 (0.50 to 2.35)
n=3
1.24 (0.94 to 1.62)
n=3
Mean year of birth 10 years laterb=0.08 (−0.08 to 0.23)
p=0.34
n=11
b=0.24 (0.01 to 0.47)
p=0.04
n=9
b=−0.15 (−0.33 to 0.02)
p=0.09
n=8
  • Figures are based on random-effects meta-analysis.

  • DoB, date of birth.