Psycho-Oncology Psycho-Oncology 19: 85–92 (2010) Published online 2 February 2009 in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/pon.1538 Illness perceptions in Greek patients with cancer: a validation of the Revised-Illness Perception Questionnaire Zoe Giannousi 1Ã , Irene Manaras 2 , Vassilis Georgoulias 1 and George Samonis 1 1 Department of Medical Oncology, University General Hospital of Heraklion, Crete, Greece 2 IST/University of Hertfordshire, Athens, Greece Abstract Objective: The Revised-Illness Perception Questionnaire (IPQ-R) assesses illness perceptions according to Leventhal’s self-regulatory model. The aim of this paper is to present findings on the reliability and validity of the IPQ-R in a population of Greek cancer patients. Methods: A total of 206 patients completed a Greek translation of the IPQ-R and the Greek version of the Beck Depression Inventory (BDI). The scale’s reliability was investigated by examining its internal consistency (Cronbach’s alpha) and its test–retest reliability. Structural validity was examined through factor analyses. Predictive validity was tested by regressing BDI scores on IPQ subscale scores. Inter-relationships between IPQ-R dimensions were also examined by computing Pearson’s Correlation Coefficients. Results: Cronbach’s alpha showed satisfactory internal consistency for the IPQ-R subscales. Paired samples’ t-test showed good test–retest reliability. Factor analysis of the IPQ-R items revealed that the Greek version reflects the structure of the original with the only difference being that the ‘Consequences’ and ‘Emotional Representations’ subscales loaded on one factor. Factor analysis of the causal dimension items revealed a different structure of Causal Representations than that of the original questionnaire yielding three main factors: Psychological Attributions, Behavioral, and External Factors. Multiple regression analyses showed that Consequences, Emotional Representations, Illness Identity, and Psychological Attributions were the best predictors for depression. Conclusions: Translation of the IPQ-R has good reliability and similar structure to that of the original. Difficulties to confirm the structure of Causal Representations may represent cultural differences in understanding illness causation. Copyright r 2009 John Wiley & Sons, Ltd. Keywords: cancer; oncology; IPQ-R; psychometric properties; depression Background Few studies provide evidence regarding cancer and Illness Perceptions (IPs). Buick et al. [1] examined differences in IPs between breast cancer patients undergoing radiotherapy and chemotherapy focus- ing on causal attributions. Chemotherapy patients reported more internal, self-blame, and environmen- tal attributions, while radiotherapy patients reported more chance attributions. Chemotherapy patients believed that their illness would last longer and have more serious consequences than radiotherapy pa- tients. More recent studies on head and neck cancer patients showed that IPs are related to physical, role, emotional, cognitive, social functioning, and global health subscales of the Quality of Life Question- naire-Cancer (30 items) (QLQ-C30) [2] and that IPs were explanatory factors of health-related quality of life outcomes [3]. It has been suggested that IPs can be used as a way to understand patients’ beliefs regarding cancer and identify patients at risk of poor psychological adjustment [1,4]. The Revised-Illness Perception Questionnaire (IPQ-R) [5] is a quantitative measure of IPs as proposed by Leventhal’s self-regulatory model [6,7]. It is an extension of the original Illness Perception Questionnaire (IPQ) [8], which con- sisted of five subscales presented in the model. Specifically, Illness Identity measures symptoms of the disease reported by the participants, Timeline refers to the perceived time frame of the illness, Consequences refer to the perceived effects that the illness has on a patient’s life, Controllability/ Curability refers to the perceived control one has over the illness, and Causes refer to the perceived reasons the disease occurred. The Revised–Illness Perception Questionnaire (IPQ-R) has improved internal consistency and * Correspondence to: Department of Medical Oncology, University General Hospital of Heraklion, PO BOX 1352, 711 10 Heraklion, Crete, Greece E-mail: zgiannousi@ hotmail.com Received: 6 February 2008 Revised: 16 December 2008 Accepted: 17 December 2008 Copyright r 2009 John Wiley & Sons, Ltd.