1Department of Psychology & Counselling, Faculty of Human Development, Sultan Idris Education University, Tanjung Malim, Malaysia; 2Department of Psychological Medicine, University Malaysia Sarawak, Sarawak, Malaysia; 3Department of Community Medicine, Universiti Sains Malaysia, Kelantan, Malaysia; 4Department of Cardiology, Institut Jantung Negara, Kuala Lumpur, Malaysia; 5Department of Cardiology, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia *Corresponding Author’s e-mails: norfirdous@fpm.upsi.edu.my and norfirdous.m@gmail.com التطوير والتحقق من صحة استبيان نوعية احلياة عرب الثقافات اخلاص بالفشل القليب نور فردو�س حممد، �شيتي رودزه غزايل، نور عزواين يعقوب، اإيزيا عزان عبدالرحيم، اأوتيه م�شكون abstract: Objectives: Heart failure (HF) is a common clinical syndrome with an enormous impact on prognosis and lifestyle. Accordingly, rehabilitation measures need to be patient-specific and consider various sociocultural factors so as to improve the patient’s quality of life (QOL). This study aimed to develop and validate a HF-specific QOL (HFQOL) questionnaire within a multicultural setting. Methods: This study took place at the National Heart Institute and Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia, between March 2013 and March 2014. A self-administered 75-item HFQOL questionnaire was designed and administrated to 164 multi-ethnic Malaysian HF patients. Exploratory factor analysis was performed to assess the instrument’s construct validity. Cronbach’s alpha coefficients were used to determine internal consistency. Results: A total of 33 out of 75 items were retained in the final tool. The HFQOL questionnaire had three common factors—psychological, physical-social and spiritual wellbeing—resulting in a cumulative percentage of total variance of 44.3%. The factor loading ranges were 0.450–0.718 for psychological wellbeing (12 items), 0.394–0.740 for physical-social wellbeing (14 items) and 0.449–0.727 for spiritual wellbeing (seven items). The overall Cronbach’s alpha coefficient of the questionnaire was 0.82, with coefficients of 0.86, 0.88 and 0.79 for the psychological, physical-social and spiritual wellbeing subdomains, respectively. Conclusion: The HFQOL questionnaire was found to be a valid and reliable measure of QOL among Malaysian HF patients from various ethnic groups. Such tools may facilitate cardiac care management planning among multi-ethnic patients with HF. Keywords: Heart Failure; Quality of Life; Culturally Competent Care; Ethnic Groups; Questionnaire Design; Reliability and Validity; Malaysia. تكون اأن يجب ذلك، على وبناًء احلياة. واأمناط التكهن على هائل تاأثري ذات �شائعة �رصيرية متالزمة هو القلب ف�شل الهدف: امللخ�ص: تدابري التاأهيل حمددة للمر�شى واأن تراعي العديد من العوامل الجتماعية والثقافية لتح�شني نوعية حياة املري�س. تهدف هذه الدرا�شة معهد يف الدرا�شة هذه اأجريت الطريقة: الثقافات. متعددة بيئة يف القلب لف�شل احلياة نوعية ا�شتبيان �شحة من والتحقق تطوير اإىل مت .2014 ومار�س 2013 مار�س بني ما الفرتة يف ماليزيا، لمبور، كوال ماليزيا، كيباجن�شان جلامعة الطبي واملركز الوطني القلب ت�شميم ا�شتبيان نوعية احلياة لف�شل القلب ذو 75 عن�رًصا باإدارة ذاتية وتوزيعه على 164 مري�شا متعدي الأعراق م�شابني بف�شل القلب. النتائج: الداخلي. الت�شاق لتحديد كرونباخ األفا معامالت ا�شتخدام مت ال�شالحية. اأدوات لتقييم ال�شتق�شائية العوامل حتليل اإجراء مت م�شرتكة- عوامل ثالثة القلب لف�شل احلياة نوعية ل�شتبيان كان النهائية. الأداة يف عن�رصا 75 اأ�شل من 33 جمموعه مبا الحتفاظ مت النف�شية والبدنية-الجتماعية والرفاهية الروحية، مما اأدى اإىل ن�شبة تراكمية من التباين الكلي من %44.3. كانت نطاقات حتميل العوامل 0.718-0.450 للرفاهية النف�شية )12 عن�رص(، 0.740-0.394 للرفاهية البدنية-الجتماعية )14 عن�رص( و 0.727-0.449 للرفاهية الروحية )�شبعة عنا�رص(. بلغ معامل األفا كرونباخ الإجمايل لال�شتبيان 0.82، مع معامالت بلغت 0.86، 0.88 و 0.79 بالن�شبة للنطاقات الفرعية م�شداقية ذو التوايل. اخلال�صة: يعترب ا�شتبيان نوعية احلياة لف�شل القلب مقيا�س والبدنية-الجتماعية والرفاهية الروحية على النف�شية وموثوق لنوعية احلياة بني مر�شى ف�شل القلب من خمتلف املجموعات العرقية. ميكن ملثل هذه الأدوات اأن ت�شهل تخطيط اإدارة الرعاية القلبية بني املر�شى متعددي الأعراق امل�شابني بف�شل القلب. الكلمات املفتاحية: ف�شل القلب؛ نوعية احلياة؛ ثقافة الرعاية املتخ�ش�شة؛ فئات عرقية؛ ت�شميم ال�شتبيان؛ املوثوقية وامل�شداقية؛ ماليزيا. Development and Validation of a Cross-Cultural Heart Failure-Specific Quality of Life Questionnaire *Nor F. Mohamed,1 Siti R. Ghazali,2 Nor A. Yaacob,3 Aizai A. A. Rahim,4 Oteh Maskon5 clinical & basic research Sultan Qaboos University Med J, November 2018, Vol. 18, Iss. 4, pp. e494–500, Epub. 28 Mar 19 Submitted 2 Apr 18 Revision Req. 28 May 18; Revision Recd. 12 Jul 18 Accepted 2 Aug 18 Advances in Knowledge - This study provides a valid and reliable heart failure (HF)-specific questionnaire to measure quality of life (QOL) in a multi-ethnic population. Application to Patient Care - The HF-specific QOL questionnaire can be used to assess the QOL of Malaysian HF patients, regardless of ethnic, cultural or religious background. - Such instruments facilitate patient-specific management by prioritising items with a lower QOL domain, enhancing the effectiveness of care as well as patient satisfaction. doi: 10.18295/squmj.2018.18.04.011 Nor F. Mohamed, Siti R. Ghazali, Nor A. Yaacob, Aizai A. A. Rahim and Oteh Maskon Clinical and Basic Research | e495 The number of heart failure (hf) patients worldwide is increasing, with the condition aff- ecting an estimated 26 million people globally.1 In Southeast Asia, the population is growing, with the majority younger than 65 years old; however, rapid epid- emiological transition has led to high rates of premature death from noncommunicable diseases, particularly cardiovascular disease.2 Southeast Asians also have a high prevalence of HF risk factors, including hypertension, tobacco smoking, physical inactivity, overweight/obesity and raised blood glucose levels. Moreover, Southeast Asian patients with HF tend to be younger and have more severe clinical features, with higher rates of mechanical ventilation and longer hospital stays compared to those in developed countries.2 In Malaysia, ischaemic heart disease is a major cause of death, with the condition contributing to 13.2% of all deaths in 2016.3 Unfortunately, as Malaysia has an ageing population, the prevalence and burden of HF is expected to increase in the future.4 Among patients with HF, quality of life (QOL) is not only affected by the physical symptoms of illness but also by a myriad of social, emotional, sexual and mental factors.5 In particular, patients may suffer from significant psychological distress due to changes in functional level, work status and family relationships.5 As such, the treatment goal in HF is not only to enhance survival rates, but to improve the patient’s QOL (i.e. meaningful survival).6,7 However, most existing QOL measures for HF patients are based on expert opinions, with only a limited number based on actual patient exp- eriences.8–11 Dunderdale et al. opined that QOL measures based on expert opinions rather than on patients’ perc- eptions might demonstrate lower accuracy and use- fulness in real-life settings.10 Furthermore, QOL may vary in the context of the patient’s unique culture and value systems and in relation to their specific goals, expectations, standards and con- cerns.6 Yusuf et al. recommended that cultural and ethnic differences be taken into consideration when designing QOL tools, especially in view of the collectivist nature of Southeast Asian communities.12 Recently, efforts have been made to maintain cultural sensitivity when developing QOL measures.13 This study there- fore aimed to develop and validate a HF-specific QOL (HFQOL) questionnaire within a multi-ethnic setting in Malaysia. Methods This study was conducted at the National Heart Institute (IJN) and Universiti Kebangsaan Malaysia Medical Centre (UKMMC), Kuala Lumpur, Malaysia between March 2013 and March 2014. A preliminary version of the HFQOL questionnaire was developed based on qual- itative findings from in-depth interviews conducted with 19 HF patients. During the interviews, the questions focused on the patients’ experiences during HF and the recovery stage; interview guides were developed based on a literature review and feedback from experts in cardiology management. Qualitative data from the inter- views were then analysed to identify themes for the quest- ionnaire constructs.14 The preliminary constructs were physical wellbeing (i.e. restrictions in physical function), social wellbeing (i.e. dependency on social support net- works), psychological wellbeing (i.e. the grieving process and negative emotions regarding adapting to the cond- ition) and spiritual wellbeing (i.e. a personal or religious belief system). Subsequently, the content of the preliminary HFQOL questionnaire was reviewed by seven experienced prof- essionals, including four cardiologists and three cardiac unit nurses, all of whom had experience managing HF patients of various ethnicities. Each reviewer was asked to rate the relevance of each item for the purposes of the tool from 1–10. They were also asked to evaluate each item’s agreement with the identified constructs, which resulted in the rephrasing of some items. The final version of the HFQOL questionnaire was admin- istered in either Malay or English, according to the respondent’s preference, and consisted of 75 items scored on a four-point Likert scale, with specific definitions tailored to each item [Table 1].15 All of the reviewers rated the final version of the questionnaire to be relevant and adequate to measure the QOL of HF patients. A pilot study of 35 HF patients confirmed the appropr- iateness of the questionnaire from a patient’s point of view. The questionnaire could be completed by the respondents either individually or with assistance from the researchers in 20 minutes. A minimum sample of 210 patients was deemed necessary based on the sample size calculations, where- in the construct with the highest number of variables (35 variables) was multiplied by five at 80% power.16 Due to the limited number of patients with HF, a convenience sampling technique was employed to recruit participants. All respondents were either in- or outpatients at the IJN and UKMMC and had HF as identified by cardiol- ogists based on the criteria of reduced left ventricular function (ejection fraction of ≤45%).17 Patients from all three major ethnic groups in Malaysia were eligible to participate in the study; however, only those able to communicate in either Malay or English were included. Patients were assessed by cardiologists for HF severity according to the classifications of the New York Heart Association (NYHA), with class I indicating no HF symptoms and no limitations in ordinary physical activity, class II indicating mild HF symptoms and slight limitations during ordinary activity, class III Development and Validation of a Cross-Cultural Heart Failure-Specific Quality of Life Questionnaire e496 | SQU Medical Journal, November 2018, Volume 18, Issue 4 indicating significant limitations in activity due to HF symptoms and class IV indicating severe limitations and HF symptoms which persist even at rest.18 All quantitative data were analysed using the Stat- istical Package for the Social Sciences (SPSS), Version 19.0 (IBM Corp., Armonk, New York, USA). Item-level descriptions were performed to explore the distribution of responses. An exploratory factor analysis (EFA) was performed to assess construct validity using a principal component analysis with varimax rotation. The Kaiser- Meyer-Olkin (KMO) measure of sampling adequacy and Bartlett’s test of sphericity was used to assess the adequacy of the sample size for the EFA.19 Scree plots and Eigen values of >1 were used to guide the number of factors, along with the construct of four domains.20 A correlation coefficient of ≥0.3 with a P value of ≤0.050 was considered statistically significant. Following the EFA, a reliability analysis was done to assess internal consistency utilising Cronbach’s alpha coefficient for each identified factor, with a coefficient of >0.70 cons- idered acceptable.21,22 The protocols of this study were approved by the IJN Ethics Committee (#IJNEC/03/2011) and UKMMC Ethics Committee (#FF-390-2011). Informed consent was obtained from all patients following screening by a cardiologist to determine their fitness to participate in the study. Results A total of 164 HF patients participated in the study, with a mean age of 61 years. The majority of patients were Malay (64%), male (68.3%) and married (81.1%). Many participants were unemployed (37.2%) and had not been educated past secondary school level (77.4%). In terms of religious beliefs, the majority were Muslims (65.9%), followed by Buddhists (16.5%), Hindus (12.2%), Christians (4.3%) and atheists (1.2%). More than half of the respondents had a family history of heart disease (52.4%) and were currently non-smokers (90.8%). Most patients were categorised as having NYHA classes I or II HF (92.1%), with only two patients (1.2%) having class IV HF [Table 2]. The KMO measure was 0.81, with significant spheri- city (P = 0.001), thus indicating that the sample size was suitable for the EFA. In total, 42 items were elimin- ated from the HFQOL questionnaire based on poor communality, inter-item correlations and factor loading. The rotated component matrix of the remaining 33 items was loaded into three rather than four common factors, due to the combination of the physical and social wellbeing constructs into a single subdomain. The first common factor, psychological wellbeing, consisted of 12 items with a factor loading range of 0.450–0.718. The second common factor was physical-social wellbeing Table 1: Example of items in each construct in a cross-cultural heart failure-specific quality of life questionnaire Item Likert score 1 2 3 4 Psychological wellbeing I feel sad whenever thinking about my health condition Almost every day of the week At least 4–6 days per week At least 1–3 days per week Never I feel depressed whenever thinking about my health condition Almost every day of the week At least 4–6 days per week At least 1–3 days per week Never Physical wellbeing Ease of breathing Difficult even without performing any activity Difficult even when performing simple activities Easy when performing simple activities Easy when performing any activity Ability to walk Impossible even with assistance Impossible without assistance Possible without assistance, but with limitations Possible without assistance or limitations Social wellbeing Interactions with family members or friends Very distant Distant The same as before Strengthened Support from family members Not supportive Less supportive than before More supportive than before Very supportive Spiritual wellbeing Level of spiritual beliefs when having heart problems None Reduced The same as before Strengthened Involvement in spiritual activities (e.g. prayer, meditation, etc.) None Reduced The same as before Strengthened Nor F. Mohamed, Siti R. Ghazali, Nor A. Yaacob, Aizai A. A. Rahim and Oteh Maskon Clinical and Basic Research | e497 Table 2: Sociodemographic and clinical characteristics of multi-ethnic Malaysian patients with heart failure (N = 164) Characteristic n (%) Gender Male 112 (68.3) Female 52 (31.7) Ethnicity Malay 105 (64) Chinese 33 (20.1) Indian 26 (15.9) Religion Muslim 108 (65.9) Buddhist 27 (16.5) Hindu 20 (12.2) Christian 7 (4.3) Atheist 2 (1.2) Marital status Single 31 (18.9) Married 133 (81.1) Education level None 12 (7.3) Primary school 51 (31.1) Secondary school 64 (39) Diploma/college/university 37 (22.6) Employment status Employed 57 (34.8) Unemployed 61 (37.2) Retired 46 (28) Smoking status Non-smoker 104 (63.4) Ex-smoker 45 (27.4) Current smoker 15 (9.1) Family history of heart disease Yes 86 (52.4) No 78 (47.6) NYHA class I 67 (40.9) II 84 (51.2) III 11 (6.7) IV 2 (1.2) NYHA = New York Heart Association. Table 3: Factor loading* of items in a cross-cultural heart failure- specific quality of life questionnaire Item Factor loading Psychological wellbeing 1. I feel sad whenever I think about my health condition 0.718 2. I feel anxious whenever I think about my health condition 0.702 3. I feel pressured whenever I think about my health condition 0.695 4. I worry whenever I think about my health condition 0.692 5. I feel depressed whenever I think about my health condition 0.660 6. My mind is troubled whenever I think about my health condition 0.630 7. I easily feel frustrated 0.619 8. I feel something is not right with my physical abilities 0.605 9. I feel inferior 0.548 10. I blame myself for the effects of my past lifestyle choices 0.485 11. I feel angry whenever I think about my physical weaknesses 0.480 12. I often cry 0.450 Physical-social wellbeing 13. Ability to climb up stairs 0.740 14. My family responsibilities have increased 0.672 15. Ability to walk 0.654 16. Ability to bend down 0.647 17. The effects of my heart problem on my health 0.621 18. Interactions with family members or friends 0.587 19. Ease of breathing 0.565 20. Level of tiredness 0.555 21. Quality of sleep 0.538 22. Ability to perform simple exercises 0.516 23. I feel less energetic than I have in the past 0.504 24. My heart problem causes a burden 0.493 25. My recent lifestyle is far better than before 0.481 26. Appetite 0.394 Spiritual wellbeing 27. Involvement in spirituality is important to me 0.727 28. My spirituality is helpful in facing my heart problem 0.725 29. Level of spiritual beliefs when having heart problems 0.673 30. During disasters, I increase my level of worship/prayer 0.603 31. The concept of life and death is decided by God 0.542 32. Involvement in spiritual activities feels peaceful 0.476 33. During disasters, I believe God protects me from danger 0.449 *Using principal axis factoring in which all items with a factor loading of >0.2 were removed from the table. Development and Validation of a Cross-Cultural Heart Failure-Specific Quality of Life Questionnaire e498 | SQU Medical Journal, November 2018, Volume 18, Issue 4 and consisted of 14 items with a factor loading range of 0.394–0.740. Lastly, the third common factor, spiritual wellbeing, consisted of seven items with a factor loading range of 0.449–0.727 [Table 3]. The cumulative percentage of total variance expl- ained by the three common factors was adequate at 44.3%, with a factor-structure coefficient of 39%. In terms of internal consistency, the first two factors (psychological and physical-social wellbeing) had Cron- bach’s alpha coefficients of >0.80, whereas factor three (spiritual wellbeing) had a value of 0.79. The overall Cronbach’s alpha coefficient for the HFQOL instrument was 0.82 [Table 4]. Discussion The current study aimed to design and validate a HFQOL questionnaire in a multi-ethnic population in Malaysia. The preliminary version of the questionnaire was designed based on the qualitative findings of in-depth interviews conducted with HF patients which sought to determine their perspectives on QOL. The four constructs identified from these interviews included physical wellbeing (i.e. restricted functionality), social wellbeing (i.e. dependency on social support), psycho- logical wellbeing (i.e. the emotional processes involved in adapting to their illness) and spiritual wellbeing (i.e. religious belief systems). The overall HFQOL and each of its three subdomains were found to be a reliable measure of QOL among Malaysian HF patients, regardless of differences in ethnicity, social background or religious beliefs. In the current study, the physical and social well- being constructs were later grouped into a single sub- domain; this may reflect the idea that physical restrictions are closely related to dependency on social support. Moreover, certain physical disabilities can be observed by others, thus affecting how a patient is treated and how that individual interacts in society.23 In Malaysia, there is a strong culture of collectivism; as such, patients rely heavily on their family and caregivers for support.24 Therefore, Malaysian HF patients who receive social support may perceive themselves to have a better QOL and improved self-care behaviours.25 On the other hand, negative perceptions of physical-social interactions may lead to negative psychological responses.26 Psychological wellbeing remained a separate sub- domain in the final HFQOL questionnaire, thus high- lighting the importance of the psychological impact of HF in determining the QOL of affected patients. Patients with HF may suffer negative psychological effects such as sadness, depression, anger and anxiety—all of which were established in the qualitative phase of the current study—due to functional disability, rehospitalisation and daily variations in symptoms, such as dyspnoea and the need for oxygen therapy.7 Among other factors, the presence of a close protective individual may strengthen the patient’s coping skills, leading to fewer psychological problems.14,27 Similarly, spiritual wellbeing also remained a sepa- rate subdomain in the final HFQOL questionnaire. This finding is interesting as it indicates that the participants considered spirituality to be a significant part of QOL, despite the multi-ethnic nature of the sample and cons- equent variations in social norms or religious beliefs. Spiritual peace has been shown to be closely related to mortality risk in HF patients; moreover, reduced spirit- uality has been associated with decreased psychological and physical wellbeing, thus indirectly contributing to less favourable outcomes as a whole.28 According to previous research, spiritual factors related to religious beliefs and practices have enabled patients with adv- anced HF to cope positively with the disease, improving their psychological wellbeing.29–31 This study was subject to certain limitations. First, as the patients were recruited from a tertiary referral hospital, the sample may not be representative of the entire HF population in Malaysia. However, the high proportion of Malay patients included in the current study is reflective of the overall demographic structure of the national population.32 The larger number of male patients also conforms to previous research indicating that heart disease is more prevalent in males.33 Second, most of the patients had less severe forms of HF as it was deemed unethical to ask severely ill patients to answer research questions that might remind them of their disabilities. This limitation also serves to explain the smaller than ideal sample size. Further research is therefore needed to assess the sensitivity of the HFQOL instrument for patients with different stages of HF. Third, the expert panel strongly recommended that two additional items—sexual rela- tionships and interest in having a life partner—be incl- uded in the questionnaire; however, these items were excluded as these concepts did not arise during the interviews. This may be due to general reluctance to discuss such topics or conservative cultural or social norms. Alternatively, this may reflect perceptions that Table 4: Internal consistency of a cross-cultural heart failure-specific quality of life questionnaire Subdomain Number of items Cronbach’s alpha coefficient Psychological wellbeing 12 0.86 Physical-social wellbeing 14 0.88 Spiritual wellbeing 7 0.79 Total 33 0.82 Nor F. Mohamed, Siti R. Ghazali, Nor A. Yaacob, Aizai A. A. Rahim and Oteh Maskon Clinical and Basic Research | e499 such factors are not important aspects of QOL for those suffering from HF, especially for those with more severe disease. Nevertheless, these factors should not be ignored in a care management plan. Conclusion The HFQOL questionnaire is a valid and reliable tool for measuring QOL among multi-ethnic Malaysian HF patients. Such tools may help cardiac and rehabilitation teams to develop patient-specific management plans. c o n f l i c t o f i n t e r e s t The authors declare no conflicts of interest. f u n d i n g This study was funded by the Malaysian Ministry of Higher Learning (RAGS #2013-0012-105-72). References 1. Ambrosy AP, Fonarow GC, Butler J, Chioncel O, Greene SJ, Vaduganathan M, et al. The global health and economic burden of hospitalizations for heart failure: Lessons learned from hospitalized heart failure registries. J Am Coll Cardiol 2014; 63:1123–33. https://doi.org/10.1016/j.jacc.2013.11.053. 2. Lam CS. Heart failure in Southeast Asia: Facts and numbers. ESC Heart Fail 2015; 2:46–9. https://doi.org/10.1002/ehf2.12036. 3. Department of Statistics Malaysia. Press release: Statistics on causes of death, Malaysia, 2017. From: www.dosm.gov.my/v 1 / i n d e x . p h p ? r = c o l u m n / p d f P r e v & i d = Y 3 p sY U I 2 Vj U 0 ZzRhZU1kcVFMMThGUT09 Accessed Jul 2018. 4. Rajadurai J, Chew D, Samion H, Pasamanickam K, Yusoff MR, Mohammad NM, et al. Malaysian CPG for heart failure. ASEAN Heart J 2014; 22:66–72. https://doi.org/10.7603/s40602-014-0012-2. 5. Cully JA, Jimenez DE, Ledoux TA, Deswal A. Recognition and treatment of depression and anxiety symptoms in heart failure. Prim Care Companion J Clin Psychiatry 2009; 11:103–9. https://doi.org/10.4088/PCC.08m00700. 6. Adebayo SO, Olunuga TO, Durodola A, Ogah OS. Quality of life in heart failure: A review. Niger J Cardiol 2017; 14:1–8. https://doi.org/10.4103/0189-7969.201914. 7. Nieminen MS, Dickstein K, Fonseca C, Serrano JM, Parissis J, Fedele F, et al. The patient perspective: Quality of life in advanced heart failure with frequent hospitalisations. Int J Cardiol 2015; 191:256–64. https://doi.org/10.1016/j.ijcard.2015.04.235. 8. Rector TS, Cohn JN. Assessment of patient outcome with the Minnesota Living with Heart Failure questionnaire: Reliability and validity during a randomized, double-blind, placebo-cont- rolled trial of pimobendan - Pimobendan Multicenter Research Group. Am Heart J 1992; 124:1017–25. https://doi.org/10.1016 /0002-8703(92)90986-6. 9. Green CP, Porter CB, Bresnahan DR, Spertus JA. Development and evaluation of the Kansas City Cardiomyopathy Question- naire: A new health status measure for heart failure. J Am Coll Cardiol 2000; 35:1245–55. https://doi.org/10.1016/S0735-1097 (00)00531-3. 10. Dunderdale K, Thompson DR, Miles JN, Beer SF, Furze G. Quality-of-life measurement in chronic heart failure: Do we take account of the patient perspective? Eur J Heart Fail 2005; 7:572–82. https://doi.org/10.1016/j.ejheart.2004.06.006. 11. Dunderdale K, Thompson DR, Beer SF, Furze G, Miles JN. Devel- opment and validation of a patient-centered health-related quality-of-life measure: The chronic heart failure assessment tool. J Cardiovasc Nurs 2008; 23:364–70. https://doi.org/10.1097/01. JCN.0000317439.82704.e8. 12. Yusuf S, Reddy S, Ounpuu S, Anand S. Global burden of card- iovascular diseases: Part II - Variations in cardiovascular disease by specific ethnic groups and geographic regions and prevention strategies. Circulation 2001; 104:2855–64. https://doi.org/10.11 61/hc4701.099488. 13. Lua PL, Salek S, Finlay I. The Malay McGill Quality of Life Questionnaire (MMQOL): Adaptation and validation. Selangor, Malaysia: University Publication Center, 2006. Pp. 5–7. 14. Mohamed NF, Azan A, Lebar O, Shaharom MH, Peterson RF. Family support, positive thinking and spirituality correlates on psychologically distressed heart failure patients. Procedia Soc Behav Sci 2014; 127:484–8. https://doi.org/10.1016/j. sbspro.2014.03.295. 15. Jackson CJ, Furnham A. Designing and Analysing Questionnaires and Surveys: A manual for health professionals and admin- istrators. London, UK: Whurr Publishers, 2000. Pp. 137–80. 16. Gorsuch RL. Exploratory factor analysis: Its role in item analysis. J Pers Assess 1997; 68:532–60. https://doi.org/10.1207/s15327 752jpa6803_5. 17. Ministry of Health Malaysia. Management of heart failure: 3rd edition clinical practice guideline 2014. From: www.acadmed. org.my/view_file.cfm?fileid=684 Accessed: Jul 2018. 18. American Heart Association. Classes of heart failure. From: www.heart.org/en/health-topics/heart-failure/what-is-heart- failure/classes-of-heart-failure Accessed: Jul 2018. 19. Worthington RL, Whittaker TA. Scale development research: A content analysis and recommendations for best practices. Couns Psychol 2006; 34:806–38. https://doi.org/10.1177/0011 000006288127. 20. Fayers PM, Hand DJ. Factor analysis, causal indicators and quality of life. Qual Life Res 1997; 6:139–50. 21. Costello AB, Osborne JW. Best practices in exploratory factor analysis: Four recommendations for getting the most from your analysis. Pract Assess Res Eval 2005; 10:1–9. 22. Bland JM, Altman DG. Cronbach’s alpha. BMJ 1997; 314:572. https://doi.org/10.1136/bmj.314.7080.572. 23. Siegrist J, Junge A. Conceptual and methodological problems in research on the quality of life in clinical medicine. Soc Sci Med 1989; 29:463–8. https://doi.org/10.1016/0277-9536(89)90295-5. 24. Yasin S, Chan CK, Reidpath DD, Allotey P. Contextualizing chronicity: A perspective from Malaysia. Global Health 2012; 8:4. https://doi.org/10.1186/1744-8603-8-4. 25. Gallagher R, Luttik ML, Jaarsma T. Social support and self-care in heart failure. J Cardiovasc Nurs 2011; 26:439–45. https://doi. org/10.1097/JCN.0b013e31820984e1. 26. Rector TS. A conceptual model of quality of life in relation to heart failure. J Card Fail 2005; 11:173–6. https://doi. org/10.1016/j.cardfail.2004.09.002. 27. Jaarsma T, Johansson P, Agren S, Strömberg A. Quality of life and symptoms of depression in advanced heart failure patients and their partners. Curr Opin Support Palliat Care 2010; 4:233–7. https://doi.org/10.1097/SPC.0b013e328340744d. 28. Park CL, Aldwin CM, Choun S, George L, Suresh DP, Bliss D. Spiritual peace predicts 5-year mortality in congestive heart failure patients. Health Psychol 2016; 35:203–10. https://doi. org/10.1037/hea0000271. 29. Dunn KS, Horgas AL. The prevalence of prayer as a spiritual self-care modality in elders. J Holist Nurs 2000; 18:337–51. https://doi.org/10.1177/089801010001800405. Development and Validation of a Cross-Cultural Heart Failure-Specific Quality of Life Questionnaire e500 | SQU Medical Journal, November 2018, Volume 18, Issue 4 30. Westlake C, Dracup K. Role of spirituality in adjustment of patients with advanced heart failure. Prog Cardiovasc Nurs 2001; 16:119–25. https://doi.org/10.1111/j.0889-7204.2001.00592.x. 31. Bekelman DB, Dy SM, Becker DM, Wittstein IS, Hendricks DE, Yamashita TE, et al. Spiritual well-being and depression in patients with heart failure. J Gen Intern Med 2007; 22:470–7. https://doi.org/10.1007/s11606-006-0044-9. 32. Liu JH, Lawrence B, Ward C, Abraham S. Social representations of history in Malaysia and Singapore: On the relationship between national and ethnic identity. Asian J Soc Psychol 2002; 5:3–20. https://doi.org/10.1111/1467-839x.00091. 33. Savarese G, Lund LH. Global public health burden of heart failure. Card Fail Rev 2017; 3:7–11. https://doi.org/10.15420/ cfr.2016:25:2.