New FDA Draft Guidance: the Importance of Literature Search in Writing IDE Protocols

The FDA recently released a draft guidance policy categorizing investigational device exemption (IDE) devices. The guidance was developed to assist the Centers for Medicare & Medicaid Services (CMS) in determining whether or not an IDE device should be covered (reimbursed) by CMS. The guidance has significant implications for research sites and investigators who are responsible for developing research budgets.

The guidance specifically addresses new devices or approved devices that have been modified for a new use and may pose significant risk. This article addresses the latter — approved devices. The FDA intends to categorize devices based on a set of criteria and whether additional non-clinical and/or clinical data on the proposed device resolve questions of safety and effectiveness.

This means that a thorough literature search during the protocol-writing is essential to ensuring the correct categorization of a device, and therefore whether CMS will cover the device and related services.

A systematic approach to literature searches

Conducting a complete literature search requires a systematic approach. No single database searches all medical literature, and the process requires an iterative approach that searches databases such as MEDLINE, EMBASE and the Cochrane CENTRAL trials register. Medical librarians are often an excellent source of structured guidance, particularly for new investigators.

Asking the right research question – PICO

To prepare for a literature search, it is important to first craft a clear research question, which often begins with a patient question or problem. A research question has four parts, often referred to as “PICO.”

  • Patient problem or population — describe the group’s or patients’ characteristics, such as primary problem, disease or health status, and demographics
  • Intervention — identify what you plan to do for that patient or population
  • Comparison — explain what is the main alternative you are considering
  • Outcomes — specify the results you plan to achieve

Focusing the search

Developing a focused search strategy allows for an efficient process that yields the most relevant results. Investigators should:

  1. Define the types of studies to be included in the search (for example, cohort studies, editorials, randomized trials, etc.).
  2. List the main topics or terms from the PICO questions that can be used in the search. It is important to also define irrelevant terms that you may want to exclude from the search.

A thorough and methodical literature search is an essential step in writing a high quality clinical research protocol. It has implications not only for the quality of the research, but for devices, a direct impact on reimbursement and clinical trial budgets.