What does this traffic sign indicate?

You answered correctly. This traffic sign indicates a first aid station or a medical facility nearby. It is a blue square sign with a white background and a red cross in the center. In Germany, such signs are used to inform drivers about places where they can get medical assistance in case of emergencies. Recognizing this sign is important, especially if you need urgent help while on the road. It does not indicate any danger or intersection, but specifically points to available first aid services.