GRP logo
Evaluating and Documenting Content Validity for the Use of Existing Instruments and Their Modification

Use of Existing Patient-Reported Outcome (PRO) Instruments and Their Modification: The ISPOR Good Research Practices for Evaluating and Documenting Content Validity for the Use of Existing Instruments and Their Modification PRO Task Force Report

The citation for this report is:
Rothman M, Burke L, Erickson P, et al. Use of Existing Patient-Reported Outcome (PRO) Instruments and Their Modification: The ISPOR Good Research Practices for Evaluating and Documenting Content Validity for The Use of Existing Instruments and Their Modification PRO Task Force Report. Value Health 2009;12;1075-83.

Task Force Chair
Margaret Rothman, PhD, Executive Director, WW Patient-reported Outcomes Center of Excellence, Johnson & Johnson Pharmaceutical Services, LLC, Washington, GA, USA

Leadership Group
Laurie B. Burke, RPh, MPH, Director, Study Endpoints and Labeling Developments, Office of New Drugs, CDER, FDA, Washington, DC, USA
Pennifer Erickson, PhD, Founder, OLGA, State College, PA, USA
Nancy Kline Leidy, PhD, Senior Vice President of Scientific Affairs, United BioSource, Bethesda, MD, USA
Donald Patrick, PhD, MSPH, Professor, University of Washington, Seattle, WA, USA
Charles Petrie, PhD, Senior Director/Group Leader, Worldwide Outcomes Research – Neurosciences, Groton, CT, USA

Background
A wide variety of Health Technology Assessors at different levels of the health system and a number of other stakeholders in medical product use consider PRO studies of efficacy and effectiveness of medical products. Although formal guidelines may not be available, good research practices in PRO development are important in improving the value of this information to decision-makers.

In July 2005, the Committee for Medicinal Products for Human Use of the European Medicines Agency issued a Reflection Paper on the Regulatory Guidance for the Use of Health Related Quality of Life (HRQL) Measures in the Evaluation of Medicinal Products. Recommendations of this Paper came into effect January 2006. The scope of the EMEA document was to discuss the place that a HRQL type of PRO may have in the drug evaluation process and to give some broad recommendations on its use in the context of already existing guidance documents. The EMEA reflection paper and existing documents also point out the need for standardization of research practices in the evaluation of medical products using PROs.

In February 2006, the U.S. Food and Drug Administration issued a draft version of Guidance for Industry titled “Patient-Reported Outcome Measures: Use in Medical Product Development to Support Labeling Claims.”

Draft FDA Guidance for Industry - Patient-Reported Outcome Measures: Use in Medical Product Development to Support Labeling Claims Draft Guidance

Chapter IV: Evaluating PRO Instruments, Part D: Modification of an Existing Instrument:

When a PRO instrument is modified, additional validation studies may be needed to confirm the adequacy of the modified instrument’s measurement properties. The extent of additional validation recommended depends on the type of modification made. For example, small nonrandomized studies may be adequate to assess the results of changing a response scale from vertical to horizontal. On the other hand, if the PRO instrument is to be used in an entirely new population of patients, a small randomized study to ascertain the measurement properties in the new population may minimize the risk that the instrument will not perform adequately in a phase 3 study. The FDA intends to consider a modified instrument as a different instrument from the original and will consider measurement properties to be version-specific. The FDA recommends additional validation to support the development of a modified PRO instrument when one or more of the following modifications occur.

The adequacy of a PRO instrument depends on the developmental history and demonstrated measurement properties. Sponsors need to identify all endpoint measurement goals to provide the basis for approval or claim substantiation. If sponsors determine that no existing instrument is applicable or adequate for their product, they can develop or modify an existing instrument. The FDA generally plans to evaluate the modified instrument in the same way that it evaluates a new instrument. It is important to have documentation supporting the original development process, modifications made and updated assessment of the measurement properties.

The FDA identifies 5 specific issues to address when modifying an existing PRO instrument:

  1. Revised Measurement Concept
  2. Application to a New Population or Condition
  3. Changed Item Content or Instrument Format
  4. Changed Mode of Administration
  5. Changed Culture or Language of Application

This Task Force will address the first three issues in its development of good research practices for assessing existing instruments for use in label claim studies, identifying the concepts contained in existing instruments, obtaining patient input if not used in original instrument, development of instruments used in a battery and modification of these instruments including use in new measurement concept, use in new population, change in item content, and assessment of measurement properties for revised instruments.

The final two issues are addressed by the PRO Task Forces bearing those names.

Draft Final Report
The Task Force presented their final draft report including responses to comments at ISPOR's 14th Annual International Meeting in Orlando. This forum session focused on issues related to the selection and use of existing PRO measures in the context of providing evidence to support a labeling claim for medical products as well as topics that need to be considered when generating and presenting evidence to support adequate content validity of existing measures used as endpoints.  The task force's presentation can be viewed at: http://www.ispor.org/TaskForces/PROIU_presentations.asp

Collectively, during two rounds of review, the task force received 41 written reviews by 52 ISPOR members submitted individually or representing an organization.  In addition, verbal comments were received during two forum presentations at the ISPOR 15th and 16th Annual International Meetings in 2010 and 2011.  Special thanks to those who reviewed and commented on the draft task force report. 


ISPOR Good Practices For Outcomes Research Index