Use of THAT

[LinaFahmi]

This question is from Chapter 6 (Modifiers) of the MGMAT SC book, question 15.

Question: The patient's rare disease was treated using novel techniques developed at the medical school.

Answer: The patient's rare disease was treated through the use of novel techniques developed at the medical school.

MY QUESTIONS:
When I initially answered this question, the sentence I came up with was "The patient's rare disease was treated by a doctor using novel techniques that were developed at the medical school".

I think the part "by a doctor" is also correct, according to the answer explanation. However, would the part "that were developed at the medical school" still correct grammatically?

[RonPurewal]

Hello,
Please post this question in the appropriate folder (= MGMAT non-CAT verbal).

Thank you.