Development and validity of the Patient-centred COPD Questionnaire (PCQ)

Area of Science:

• Pulmonary Medicine
• Health Outcomes Research
• Psychometrics

Background:

• Current Chronic Obstructive Pulmonary Disease (COPD) guidelines emphasize evaluating airway obstruction and health status for optimal treatment.
• Existing health status questionnaires, like the Clinical-COPD-Questionnaire and COPD-Assessment-Test, have limitations in structure, content, and methodology.
• There is a need for a COPD-specific instrument that effectively measures patient-reported impairment.

Purpose of the Study:

• To develop and validate a new COPD-specific questionnaire, the Patient-centred-COPD-Questionnaire (PCQ).
• To assess the psychometric properties, including reliability and validity, of the PCQ.
• To evaluate the PCQ's ability to capture the impact of COPD on patients' daily lives.

Main Methods:

• Focus groups with COPD patients and healthcare providers informed item generation.
• Exploratory Factor Analysis (EFA) on 80 candidate items (n=541) identified key dimensions.
• Confirmatory Factor Analysis (CFA), construct, and concurrent validity assessments were performed (n=412).

Main Results:

• EFA revealed a reliable three-component solution: 'shortness of breath', 'acceptance of COPD', and 'confidence in care'.
• CFA confirmed this three-dimensional model.
• Significant correlations were found between PCQ subscales and other health measures, with more severely ill patients reporting greater impairment.

Conclusions:

• The PCQ is a reliable and valid 18-item questionnaire for assessing COPD's impact on daily life.
• It offers a unique dimension of 'confidence in care', addressing a gap in existing COPD assessment tools.
• The PCQ provides a patient-centred approach to understanding and managing COPD.