Final answer:
The statement is false; additional signs and symptoms should be coded when present as they can provide important clues and help in diagnosing atypical presentations of diseases.
Step-by-step explanation:
The statement is False. Additional signs and symptoms that may not routinely be associated with a disease should indeed be coded when present as they can provide important diagnostic clues for healthcare providers. While a specific group of signs and symptoms might characterize a particular disease, forming what is known as a syndrome, many diseases can have overlapping signs and symptoms. Thus, it's crucial to record all pertinent clinical features even if they are not the most common or characteristic for the disease. Moreover, some diseases may present with atypical signs and symptoms, or none at all, such as in asymptomatic presentations. For accurate diagnosis and treatment, medical professionals must consider both typical and atypical manifestations of diseases.