Table 5 Difference between the mean chronological and estimated ages and their concordance

Age category

20–30

4.56

3.28; 5.83

 < 0.001

0.314

0.132; 0.497

0.001

31 40

1.32

 − 0.65; 3.27

0.181

0.338

0.140; 0.535

0.001

41–50

 − 2.48

 − 4.70; − 0.26

0.03

0.125

 − 0.066; 0.316

0.199

51–60

 − 5.1

 − 7.52; − 2.68

 < 0.001

0.106

 − 0.032; 0.244

0.133

61–70

 − 8.95

 − 11.77; − 6.12

 < 0.001

0.019

 − 0.091; 0.128

0.737

71–80

 − 9.51

 − 12.34; − 6.67

 < 0.001

0.134

 − 0.038; 0.307

0.128