Qualitative interviews to evaluate content validity of the ACTIV-2 COVID-19 Symptom Diary (ACSD)

Patient-reported outcome measures are needed to assess the impact of treatments for COVID-19 on symptoms. The ACTIV-2 COVID-19 Symptom Diary (ACSD) is being used in the ongoing Accelerating COVID-19 Therapeutic Interventions and Vaccines-2 (ACTIV-2) platform clinical trial. The purpose of the current study was to conduct qualitative interviews to assess content validity of the ACSD.

Interviews were conducted with adults who had tested positive for SARS-CoV-2. The ACSD begins with global items, followed by a symptom checklist. Each interview began with concept elicitation focusing on participant experiences with COVID-19. Then, participants completed the ACSD, and cognitive interviews were conducted to evaluate the questionnaire. Interviews were recorded, transcribed, and coded following a qualitative content analysis. For the qualitative analysis, a coding dictionary was developed with a list of all potential codes and instructions for how the codes should be applied and combined.

Interviews were conducted with 30 participants (mean age = 39 years; 57% female; 17% Latinx; 17% Black/African American; 40% meeting at least one criterion for classification as high risk of progression to severe COVID-19). Commonly reported symptoms included fatigue (reported by 100% of the sample), body pain/muscle pain/aches (87%), headaches (87%), cough (83%), loss of smell (73%), shortness of breath/difficulty breathing (70%), and chills (70%). The 13 symptoms most commonly reported in this study are included in the ACSD. After completing the ACSD, participants consistently reported that it was clear and easy to complete, and all items were generally interpreted as intended. Based on participants' input, the ACSD was edited slightly after the first 13 interviews, and the revised version was used for the final 17 interviews. Two additional items assessing "brain fog" and dizziness were recommended for addition to the ACSD in future research.

This qualitative study supports the content validity of the ACSD for assessment of COVID-19 symptoms. Quantitative research with larger samples will be needed to examine the questionnaire's measurement properties.