Figure 2.

Screenshot of a vignette and the questions asked. All questions were compulsory, except for the last one. To avoid order effects, general practitioners (GPs) were randomly assigned to view the response categories in 1 of 2 orders: order 1 (depicted here) presented the response categories in the order of “yes,”“no” (chest X-ray question) and “refer to specialist urgently,”“refer to specialist routinely,”“not refer at this stage” (referral question). Order 2 presented the response categories in the opposite order for both questions. Order was held constant for a given GP across parts A and B.