While there should be a diagnosis to support each procedure, it is NOT necessary to have the same number of diagnoses as procedures. Why is this?

What will be an ideal response?

Answer: Students should answer something like the following: ICD-10-CM provides many combination codes for diagnoses, but ICD-10-PCS does not use combination codes, even for procedures that are commonly performed together. One combination code can describe multiple conditions, but multiple procedure codes may be needed to properly identify all procedures performed on the patient.