Final answer:
The use of an external cause code from Chapter 20 is not required if the external cause and intent are included in a code from another chapter, such as the accidental poisoning by penicillin represented by code T36.0X1-, which is true.
Step-by-step explanation:
The statement about the use of an External cause code from Chapter 20 is True. If the external cause and intent of the injury or health issue are included in a code from another chapter, it's not necessary to use a separate external cause code from Chapter 20. This is because the primary code, for instance, T36.0X1-, already specifies the nature of the injury (poisoning by penicillin) and the intent (accidental). Therefore, the additional external cause code would be redundant in this scenario.