Background: The field of long COVID research is rapidly evolving, however, tools to assess and monitor symptoms and recovery of the disease are limited. The objective of the present study was to develop a new patient-reported outcomes instrument, the Symptoms Evolution of Long COVID‑19 (SE-LC19), and establish its content validity.
Methods: The 40-item SE-LC19 instrument was developed based on patient-relevant empirical evidence from scientific literature and clinical guidelines that reported symptoms specific to long COVID.
Objectives: There is limited qualitative research on patients' experiences with long COVID-19, and how specific symptoms impact their daily lives. The study aimed to understand patients' lived experiences of long COVID-19 and to develop a conceptual model representing the symptoms and their impact on overall quality of life.
Setting: Qualitative study consisting of a comprehensive literature review, and in-depth clinician and patient semistructured interviews.