J. of Biomed. & Clin. Sci. Dec 2017 Vol 2 (2), 8-13 Original Article http://apps.amdi.usm.my/journal/ [8] 1 INTRODUCTION One of the commonest psychiatric sequelae associated with cancer is depression and anxiety. In a multicentre study in Canada which involved 10,153 cancer patients, across all cancer types, 19% of patients presented with clinical level of anxiety and 12.9% presented with clinical level of depression [1]. In the Asian context, a study in Iranian cancer patients reported 16.7% of patients exhibited symptomatic anxiety while 21.3% of patients presented with symptomatic depression [2]. A Malaysian study of breast cancer patients reported even higher prevalence of anxiety which affects 31.7% of patients while depression is reported in 22% of patients [3]. The focus on positive psychology in cancer patients has been of particular importance recently as positive psychology may reduce the occurrence of psychological distresses such as depression and anxiety in cancer patients and may also improve the quality of life of cancer patients. Optimism is the stable tendency to believe good things rather bad things will happen in life [4]. There are two components in the assessment of optimism i.e. the optimism component evaluates the degree of positive expectancy of a person for their future while pessimism component assesses the degree of negative expectancy of a person for their future [4]. It is important to study optimism as evidence has shown optimism influence physical and mental well-being by promoting healthier lifestyle with better adaptive coping and cognitive responses, and greater problem solving capability. Optimism has also been shown to enhance quality of life [5]. With regard to cancer patients, optimism has been shown to be Validation of the Malay Version of the Life Orientation Test-Revised (LOT-R) among Malaysian Cancer Patients Abstract — It is important to study optimism as it is negatively correlated with anxiety and depressive and positively correlated with quality of life in cancer patients. This study translated and investigated the psychometric properties of the Malay version of the Life Orientation Test-Revised (LOT-R) among Malaysian cancer patients. The validated Malay version of the LOT-R will be used for assessing level of optimism among Malaysian cancer patients in future studies and determine factors associated with it in order to design effective psychosocial intervention which will enhance level of optimism in cancer patients. Concurrent translation and back translation of original English version of the LOT-R to Malay was performed and the Malay version was administered to 195 cancer patients of different cancer diagnoses at baseline assessment and repeated 2 months later at follow up. Reliability was assessed with internal consistency (Cronbach’s α) and test -retest reliability (intraclass correlation coefficient), validity was assessed with face, content, convergent, and discriminant validities. Construct validity was examined with exploratory factor analysis. Two third of the participants (n = 129/195; 66%) were of middle age, three forth were females (n = 142/195; 72.8%) and eight tenth were Malays (n = 160/195; 82.1%). The LOT-R (Malay) total score (Cronbach’s α = 0.58; ICC = 0.62) and its domains (Cronbach’s α [Optimism) = 0.60; Cronbach’s α[Pessimism) = 0.42; ICC[Optimism] = 0.61; ICC[Pessimism] = 0.59) demonstrated questionable internal consistencies but acceptable test-retest reliability. Convergent and discriminant validities were achieved by the LOT-R (Malay). Construct validity was also demonstrated by the LOT-R (Malay) as exploratory factor analysis showed that all the items had factor loadings > 0.4. The LOT-R (Malay) has acceptable psychometric properties and suitable to assess optimism in Malaysian cancer patients. It should be validated for use in other Malaysian populations. Keywords — Life Orientation Test-Revised (Malay), Malaysian cancer patients, reliability, validity Leong Abdullah MFI 1 , Hami R 1 , Nizuwan A 2 , Mohd Sharif N 1 , Appalanaido GK 3 , Md Sharif SS 1 Lifestyle Science Cluster, 2 Division of Research and Networking, 3 Oncological & Radiological Science Cluster, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, 13200 Kepala Batas, Pulau Pinang, Malaysia. Received 14 Apr 2017. Revised 02 Aug 2017. Accepted 22 Aug 2017. Published Online 01 Dec 2017 *Corresponding author: Mohammad Farris Iman Leong Abdullah E-mail: farris@usm.my