Relationship between advertisement-recruited and street-recruited participants in differences between inner urban and suburban route environments. The mean values are expressed as sex-neutral means. The solid diagonal line represents the line of identity (slope = 1.0 and y-intercept = 0.0). The dotted line represents the linear regression line. The upper and lower dashed lines on either side of the linear regression line represent the 95% confidence interval (CI). The regression line (y = -0.19 [-0.44 - 0.06] + 1.29 [1.17 - 1.42] ×, [95% CI]) deviated slightly from the line of identity. Note that the means are sometimes minus values. The interpretation of the y-intercept could therefore be misleading. The 95% CI for the slope therefore gives a better picture, showing that the linear regression line deviated slightly from the line of identity. Pearson's correlation was 0.98.