Published online Feb 15, 2020. doi: 10.4251/wjgo.v12.i2.205
Peer-review started: October 7, 2019
First decision: October 18, 2019
Revised: October 29, 2019
Accepted: January 6, 2020
Article in press: January 6, 2020
Published online: February 15, 2020
Processing time: 130 Days and 20 Hours
A content valid assessment of neuropathy is needed for clinical research among colorectal cancer (CRC) patients receiving oxaliplatin. The authors assessed the content validity of the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity (FACT/GOG-Ntx) scale among CRC patients who had received oxaliplatin. The measure exhibited good content validity. Moreover, patients reported that foot neuropathy was most bothersome for them. This study is significant because the authors provide evidence that the FACT/GOG-Ntx is suitable for use in clinical trials and other research studies of this population.
This study examines the neuropathy experiences of CRC patients and the appropriateness (i.e., content validity) of a patient reported outcome measure of neuropathy. These topics are important to examine because patient reported outcome measures are needed to assess drug side effects in clinical trial settings.
The main objective was to test the content validity of FACT/GOG-Ntx. This objective was realized; the measure was found to have content validity and can be used in future research and clinical practice.
The authors used semi-structured patient interviews to assess the FACT/GOG-Ntx. Semi-structured interviews entail using a set list of questions, administered by a trained interviewer. Interviews typical contain a combination of closed-ended and open-ended questions. By using pre-planned and spontaneous probing questions, the interviewer is able to gather a detailed description of the key topics from the perspective on the interviewee.
The qualitative concept elicitation data, in combination with data from cognitive interviews and the literature, provide moderate to strong support for the content validity of 11 the 13 items of the FACT/GOG-Ntx-13. Two items - “I have trouble hearing” (NTX6) and “I get a ringing of buzzing in my ears” (NTX7), had limited support in our data. However, limited support is not surprising given that hearing impairment is a symptom of severe neuropathy, and oxaliplatin therapy may be discontinued or reduced prior to impacting hearing. The authors recommend retaining these items as indicators of severe neuropathy.
The FACT/GOG-Ntx has content validity for CRC patients receiving oxaliplatin. Patients related more with the term “discomfort” than “pain” when reporting neuropathy in their hands and feet. The FACT/GOG-Ntx has content validity for CRC patients receiving oxaliplatin. This study builds upon the body of evidence supporting the use of the FACT/GOG-Ntx in future research and clinical practice.
Existing patient reported outcome measures can be tested for their validity in new, specific populations. The authors anticipate continued advancement in the use of patient reported measures in clinical research and in drug development. Future work on the use of patient reported outcomes measures in clinical practice is best suited for a combination of patient-focused, qualitative research and large, quantitative surveys to assess measurement properties.