New Study Evaluates Quality-of-Life Instruments for Patients With PAH

Researchers have assessed the psychometric properties of existing quality-of-life (QOL) tools for evaluating patients with pulmonary arterial hypertension (PAH). The systemic review, published in Respiratory Medicine, offers comprehensive analysis and insight into the strengths and shortcomings of 4 available assessment tools.¹

The review, which followed the 2018 Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines, included a detailed review of 4 QOL instruments: Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR), Living with Pulmonary Hypertension Questionnaire (LPHQ), emPHasis-10, and PAH-SYMPACT.

The researchers noted, "Despite some sample size limitations, these instruments demonstrated varying degrees of internal reliability, validity, and content coverage for assessing quality of life in pulmonary arterial hypertension patients."

The CAMPHOR assessment tool was awarded a Grade A rating, as it has demonstrated excellent internal reliability (Cronbach's α = 0.76-0.92) across multiple studies. Developed in 2006, it consists of 65 items spanning symptoms, functioning, and overall QOL. It also distinguishes itself by addressing nuanced aspects like planning activities and the perception of losing control over one's body. CAMPHOR's domains (energy, mood, and physical functioning) strongly correlate with established measures like the Nottingham Health Profile (NHP) and SF-36.^2-5 However, it is the longest-developed instrument, which may limit routine use in clinical settings.

The authors of this analysis emphasize the need for research to employ more rigorous methodologies to enhance the reliability and validity of QOL assessment tools for patients with PAH. | Image Credit: © Kiattisak-stock.adobe.com

PAH-SYMPACT also earned a Grade A rating for its concise 22-item format and high reliability (Cronbach's α > 0.80). It is one of the few tools that assess mental well-being alongside physical symptoms.

The LPHQ is a 21-item questionnaire. Although it performs well in internal consistency (Cronbach's α = 0.87), it received a Grade B rating due to "low-quality evidence for an indeterminate internal consistency and negative structural validity of the instrument." Despite these shortcomings, it addresses unique aspects like financial well-being and difficulty maintaining relationships.

The emPHasis-10 is a 10-item tool designed for quick assessment using a semantic differential scale and has excellent internal reliability (Cronbach's α = 0.90-0.98). Despite its ease of use and internal reliability, it received a Grade B rating due to "an indeterminate internal consistency and structural validity of the instrument, since the authors did not fully state the fit indices of the Rasch analysis."

Despite its comprehensive analysis, the review has notable limitations. Many studies relied on Cronbach’s α to assess internal consistency, which, although widely used, may not adequately reflect the multidimensional nature of QOL instruments. Recent guidelines recommend the omega hierarchical coefficient (ω_H) as a more effective alternative.⁶ Additionally, the review excluded studies published in languages other than English, Italian, and Spanish, potentially introducing selection bias.

Patient-reported outcomes play a critical role in understanding the patient's view of their health status. The authors note that "There is currently no gold standard for QOL assessment in PAH patients, though this would significantly enhance care," adding that "Generic instruments like the SF-36 and Nottingham Health Profile (NHP) have been used to assess QOL, but they often lack specificity for PAH-related concerns."

Although CAMPHOR and PAH-SYMPACT stand out as the most reliable tools, the authors caution that "critical evaluation of these tools highlights incomplete psychometric assessments and methodological limitations in reference studies," emphasizing the need for future research to employ more rigorous methodologies in order to enhance the reliability and validity of QOL assessment tools for patients with PAH.

References

1. Irene G, Cedrone N, Lommi M, Iovino P, Vellone E. Appraisal and evaluation of the quality of life in pulmonary arterial hypertension instruments: a systematic review using COSMIN methodology. Respir Med. 2024;234:107829. doi:10.1016/j.rmed.2024.107829

2. McKenna SP, Doughty N, Meads DM, Doward LC, Pepke-Zaba J. The Cambridge pulmonary hypertension outcome review (CAMPHOR): a measure of health-related quality of life and quality of life for patients with pulmonary hypertension. Qual Life Res. 2006;15(1):103-115. doi:10.1007/s11136-005-3513-4

3. Aguirre-Camacho A, Stepanous J, Blanco-Donoso LM, et al. Adaptation and validation of the Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) for use in Spain. Rev Esp Cardiol (Engl Ed). 2017;70(6):467-473. doi:10.1016/j.rec.2016.11.007

4. Gomberg-Maitland M, Thenappan T, Rizvi K, Chandra S, Meads DM, McKenna SP. United States validation of the Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR). J Heart Lung Transplant. 2008;27(1):124-130. doi:10.1016/j.healun.2007.10.004

5. Ganderton L, Jenkins S, McKenna SP, et al. Validation of the Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) for the Australian and New Zealand population. Respirology. 2011;16(8):1235-1240. doi:10.1111/j.1440-1843.2011.02030.x

6. Cho E. Reliability and omega hierarchical in multidimensional data: a comparison of various estimators. Psychol Methods. Published online September 1, 2022. doi:10.1037/met0000525