BACKGROUND: Current studies reveal a lack of consensus for the evaluation of physical and psychosocial problems after ICU stay and their changes over time. OBJECTIVES: The aim was to develop and evaluate the validity and reliability of a questionnaire for assessing physical and psychosocial problems over time for patients following ICU recovery. PATIENTS: Thirty-nine patients completed the questionnaire, 17 were retested. METHODS AND RESULTS: The questionnaire was constructed in three sets: physical problems, psychosocial problems and follow-up care. Face and content validity were tested by nurses, researchers and patients. The questionnaire showed good construct validity in all three sets and had strong factor loadings (explained variance >70%, factor loadings >0.5) for all three sets. There was good concurrent validity compared with the SF 12 (r(s)>0.5). Internal consistency was shown to be reliable (Cronbach's alpha 0.70-0.85). Stability reliability on retesting was good for the physical and psychosocial sets (r(s)>0.5). CONCLUSION: The 3-set 4P questionnaire was a first step in developing an instrument for assessment of former ICU patients' problems over time. The sample size was small and thus, further studies are needed to confirm these findings.