Psychometric evaluation of 3-set 4P questionnaire

Area of Science:

• Intensive Care Medicine
• Psychometrics
• Health Outcomes Research

Background:

• Former intensive care unit (ICU) patients often experience significant physical and psychosocial problems.
• Assessing these long-term effects and the need for follow-up care is crucial for patient recovery.
• Existing instruments may not fully capture the multifaceted needs of this population.

Purpose of the Study:

• To psychometrically test and evaluate the 3-set 4P questionnaire in a larger population of former ICU patients.
• To assess the validity and reliability of the questionnaire for measuring physical, psychosocial, and follow-up needs.
• To refine the 3-set 4P as a tool for post-ICU care assessment.

Main Methods:

• The 3-set 4P questionnaire was mailed to former ICU patients (length of stay >24 hours) across four Swedish ICUs.
• Exploratory factor analysis (Varimax rotation) was used for construct validity.
• Concurrent validity was assessed using the SF-36, and stability reliability was determined via test-retest analysis.

Main Results:

• Factor analysis yielded 3 factors (physical), 5 factors (psychosocial), and 4 factors (follow-up), with strong loadings and 62-77.5% explained variance.
• Concurrent validity showed moderate correlations (Spearman's r(s) 0.3-0.6) with SF-36 for most questions.
• Test-retest reliability was strong to moderate for follow-up, and moderate to fair for physical and psychosocial sets, potentially due to rapid status changes.

Conclusions:

• The 3-set 4P questionnaire demonstrates overall acceptable psychometric properties for assessing post-ICU physical and psychosocial problems.
• The instrument shows good internal consistency (homogeneity) across all three sets.
• Further cross-cultural modification is recommended before the 3-set 4P can be fully implemented in clinical practice.