The Turkish versions of the revised illness perception questionnaire (IPQ-R) and the brief illness perception questionnaire (Brief IPQ): Pilot validation in Turkish migrants living in Germany

Background: As compared to the majority population, Turkish migrants living in Germany experience more problems in coping with chronic diseases. This may in part be due to culture-specific illness perceptions. Hence, the consideration of these perceptions by health professionals is essential to provide adequate health care in this population group. The Revised and Brief Illness Perception Questionnaire (IPQ-R, Brief IPQ) proved being valuable instruments for this purpose. However, no validations for Turkish migrants living in Germany exist. This study aimed at pilot validating both instruments, also examining obstacles for a confirmatory factor validation.
Methods: 82 Turkish migrant patients (58.5% female) with different chronic diseases were recruited from rehabilitation clinics and self-help groups in North Rhine-Westphalia, Germany. Construct, convergent, and divergent validity and internal consistency of the Turkish IPQ-R and the translated Brief-IPQ (obtained by forward/backward translation) were assessed. Validation measures included the PANAS and SF-12. Questionnaires were interviewer- and self-administered using an in-house approach. A supplemental qualitative study examined obstacles in the recruitment process and highlighted problems in the adapted questionnaires.
Results: Structural validity of the IPQ-R part-II was slightly lower than in the Turkish validation study. Cronbach’s alpha ranged from 0.72 for “coherence” and 0.57 for “timeline acute/chronic”, however was only 0.36 for “timeline cyclical”. The four-factor structure of the IPQ-R part-III could not be confirmed. Instead, three factors have been extracted. Unlike in the Turkish validation study, part-I was not understood by Turkish migrants. The validity of the translated Brief IPQ was similar to the original version.
Conclusion: Participants experienced problems with completing the Turkish IPQ-R. This indicates differences between Turks living in Turkey and Turkish migrants living in Germany that are relevant for psychometric properties of instruments. Re-adaptation of the IPQ-R to Turkish migrants is necessary before it can be applied in research on this population group.