Refinement and Validation of the Head and Neck Lymphedema and Fibrosis Symptom Inventory.

Abstract

Lymphedema and fibrosis (LEF) are common yet overlooked late effects of head and neck cancer and its therapy. Lack of reliable and valid measures of head and neck LEF is a critical barrier to the timely identification and management of head and neck LEF. To fill this gap, we developed and pilot tested a 64-item patient-reported outcome measure ( Lymphedema Symptom Intensity and Distress Survey-Head and Neck, LSIDS-H&N). This article aims to report the process of further validation and refinement of the tool. A prospective, longitudinal study was conducted, and 120 patients with oral cavity and oropharyngeal cancer were recruited. Participants completed the LSIDS-H&N at pretreatment, end of treatment, and every 3 months up to 12 months after treatment. SAS PROC VARCLUS was used to generate preliminary clusters of item responses. Internal consistency of the item responses within each cluster was assessed using Cronbach's alpha. A total of 117 patients completed the study. The participants reported that the LSIDS-H&N was easy to understand and captured their symptoms and medical conditions. However, >50% of participants indicated that the survey was burdensome due to length. Thus, we proceeded with item reduction, and the shortened tool (33-item) was named Head and Neck Lymphedema and Fibrosis Symptom Inventory (HN-LEF Symptom Inventory). The subsequent exploration of symptom clusters identified 7 symptom domain clusters (eg, soft tissue and neurologic toxicity), all of which demonstrated good internal consistency. The HN-LEF Symptom Inventory has been carefully developed and refined to allow clinicians and researchers to capture LEF-associated symptom burden and function impairments. Additional rigorous psychometric testing of the tool is ongoing to further validate the strength and internal validity of this tool.