Table 4 Threshold effect analysis of serum carotenoids on VAI using piece-wise linear regression
VAI | Adjusted β (95% CI) P value | |
|---|---|---|
α-carotene | ||
One line slop | −0.26 (− 0.31, − 0.20) < 0.0001 | |
Log likelihood ratio test | 0.071 | |
β-carotene | ||
Inflection point (K) | 2.44 | |
<K slope | −0.63 (− 0.89, − 0.37) < 0.0001 | |
>K slope | −0.33 (− 0.40, − 0.25) < 0.0001 | |
Log likelihood ratio test | 0.038 | |
β-cryptoxanthin | ||
One line slop | −0.24 (− 0.32, − 0.17) < 0.0001 | |
Log likelihood ratio test | 0.447 | |
Lutein/zeaxanthin | ||
One line slop | −0.26 (− 0.37, − 0.15) < 0.0001 | |
Log likelihood ratio test | 0.354 | |
Trans-lycopene | ||
Inflection point (K) | 3.80 | |
<K slope | −0.11 (− 0.27, 0.06) 0.1966 | |
>K slope | −0.47 (− 0.62, − 0.33) < 0.0001 | |
Log likelihood ratio test | 0.005 |