Final answer:
Chronological classification is the type of patient file classification that uses a time frame of 6 months or longer.
Step-by-step explanation:
The type of patient file classification that uses a time frame of 6 months or longer is Chronological classification. Chronological classification organizes patient files according to the date and time of their medical visits or treatments. This type of classification allows healthcare providers to easily track the progression of a patient's medical history over an extended period of time.