OBJECTIVE: No outcome measures specific to pulmonary hypertension (PH) currently exist. The aim of the study was to develop health-related quality of life (symptoms and functioning) scales and a quality of life scale that would allow comprehensive, accurate and valid patient-reported outcome assessment in clinical studies.
METHODS: The content of the Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) was derived from qualitative interviews conducted with 35 patients. Item reduction was based on the analysis of responses to a postal survey (n=75) and patient interviews (n=15) designed to determine face and content validity. A final postal validation study (n=91) was performed to determine reproducibility and construct validity.
RESULTS: The questionnaire was well received by participants who found it to be relevant, comprehensible and quick and easy to complete. Rasch and factor analyses were conducted to ensure unidimensionality of the final CAMPHOR scales; Overall symptoms (made up of Energy, Breathlessness and Mood subscales), Functioning and Quality of life. The CAMPHOR scales had good internal consistency (alpha=0.90-0.92) and reproducibility (test-retest correlations=0.86-0.92). They also exhibited convergent, divergent and known groups validity.
CONCLUSIONS: The CAMPHOR is a valuable new instrument for assessing patient-reported outcome in PH clinical trials and routine practice.