Patient-reported outcome measures are essential for assessing health-related quality of life (HRQoL) in both research and clinical practice. The Pulmonary Embolism Quality of Life (PEmb-QoL) questionnaire is a disease-specific instrument designed to measure HRQoL in patients with pulmonary embolism (PE). This study aimed to evaluate the psychometric properties of the Danish electronic version of the PEmb-QoL questionnaire.
Psychometric validation study.
Eligible patients received a digital mail 6 months after their diagnosis, with an invitation to complete an online questionnaire. A subset of patients completed a second time 7–10 days following the initial completion.
Adult patients diagnosed with PE in Denmark between March 2022 and May 2023 were included in the study.
The main outcome measure was the PEmb-QoL summary score. Validation procedures included assessments of targeting, internal reliability (IR), test–retest reliability, differential item functioning (DIF) and concurrent validity.
The study included 1017 patients. The Danish PEmb-QoL demonstrated robust IR (IR=0.95 for the total score) and adequate test–retest reliability for most domains (relative G-coefficients>0.7). However, DIF analysis revealed subgroup differences for some items, particularly those related to daily activity limitations and pain. Targeting analysis indicated moderate alignment between latent score distributions and item response distributions, with ceiling effects noted in several domains. The PEmb-QoL exhibited strong correlations with the Post-Venous Thromboembolism Functional Status Scale (r=0.82) and EuroQol-5 Domain (r=0.73), and moderate correlations with Generalised Anxiety Disorder Questionnaire (r=0.47) and Patient Health Questionnaire (r=0.57), confirming its concurrent validity.
While some items in the PEmb-QoL instrument performed inadequately on DIF and targeting, the expected overall score and the concurrent validity did not seem to be compromised by these issues. Thus, it is likely that a reduced version of the electronic Danish PEmb-QoL will possess suitable psychometric properties for measuring HRQoL in patients with PE.