OBJECTIVES: Diagnosing and assessing long COVID can be challenging, leading to potential under-diagnosis and missed opportunities. The use of Patient-Reported Outcomes (PROs) can improve this. We aimed to understand the use of PRO instruments in long COVID clinical studies and the respective measured relevant concepts, from the patient’s perspective.

METHODS: A review of qualitative studies from Medline and PsychInfo databases in long COVID was conducted to discover concepts relevant to these patients. Additional searches were performed in ePROVIDE^TM databases, ClinicalTrials.gov, and Medline to identify PRO instruments that have been used, and those specifically developed for long COVID patients, and their corresponding concepts.

RESULTS: The review of 14 qualitative studies and six online patient stories revealed concepts relevant to long COVID patients, including signs and symptoms, physical functioning, quality of life, emotional functioning, cognitive functioning, and impact on work/school. Thus far, there are eight PRO instruments developed specifically for long COVID, all described in PROQOLID database. Nevertheless, across the review of clinical studies, only 4% of the total PROs identified in long COVID studies were long COVID-specific instruments, compared to 96% for generic and other disease-specific PROs. The PROs used in the studies measured a variety of concepts, including physical functioning, fatigue, mental health, cognitive functioning, and dyspnea. However, some important concepts to long COVID patients (including activities of daily living, social functioning, illness journey, family functioning, and coping) were assessed in less than 5% of the studies.

CONCLUSIONS: There are limited number of PROs specifically developed for the assessment of long COVID, which are used in a small number of studies. Moreover, some key concepts that are important for the patients are rarely assessed in clinical studies. Our findings highlight the need for additional research in this area and for further development of long COVID-specific PROs to include these important concepts.