FIGURE 6.

Dose-response relations between circulating concentrations of total carotenoids (A; n = 1757), α-carotene (B; n = 2191), β-carotene (C; n = 2296), β-cryptoxanthin (D; n = 2191), lutein and zeaxanthin (E; n = 2191), and lycopene (F; n = 2296) and RRs of bladder cancer in adults. Data were modeled with random-effects restricted cubic spline models with 4 knots (5^th, 35^th, 65^th, and 95^th percentiles) and using the Greenland and Longnecker method (29) to estimate the covariances of multivariable-adjusted RRs. Lines with long dashes represent the pointwise 95% CIs for the fitted nonlinear trend (solid line). Lines with short dashes represent the linear trend.