Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
SiC Index, descriptive statistics: number of subject, mean value ± standard deviation. Number (percentage) of subjects with SiC Index >3.
| Year | number of subjects | SiC mean ± SD | SIC>3 n (%) |
| 1989 | 123 | 7.8 ± 0.7 | 123 (33.0) |
| 1992 | 104 | 7.4 ± 1.2 | 96 (30.5) |
| 1995 | 135 | 5.6 ± 1.8 | 77 (18.7) |
| 1999 | 133 | 5.5 ± 2.1 | 71 (17.5) |
| 2004 | 99 | 3.90 ± 2.8 | 37 (12.4) |
| Anova one way p < 0.001 | χ2 p < 0.01 |
The percentage of subjects with a SIC>3 was calculated on the total of the cohort.
