KLK3 and Anxiety: Patients registered with a GP with a high score on anxiety caused by uncertainty (odds ratio [OR] 1.03, 95% confidence interval [CI] = 1.00 to 1.06, P = 0.025) or concern about bad outcomes (OR 1.04; 95% CI = 1.00 to 1.08, P = 0.034) were more likely to have an incident PSA test, whereas those registered with a GP with increased tolerance for ambiguity were less likely (OR 0.98, 95% CI = 0.96 to 1.00, P = 0.025).