Which of the following is NOT considered a change by choice of the worker?

The correct choice identifies a situation that is fundamentally aligned with the worker's agency in deciding their medical treatment options. A change requested by the worker is clearly within their rights and represents a proactive decision on their part regarding their care. This emphasizes the worker's involvement and choice in their medical journey, which is a recognized part of their rights regarding treatment decisions.

In contrast, the other options describe instances where the worker may not have direct control or say in how their medical needs are addressed. Emergency services by a physician, referrals to radiologists, and a Worker Requested Medical Exam (WRME) involve actions where the worker's input is either minimal or predetermined by medical necessity or procedural guidelines. These options highlight scenarios where decisions are made by healthcare professionals or dictated by the circumstances surrounding the worker's condition, thus making them changes that are not purely at the worker's discretion.