1. Quality of life Hermann P.G. Schneider, Alastair MacLennan and David Feeny

2. Outline Definitions: health status and health-related quality of life Important measurement properties Determinants of health status and health-related quality of life Assessing health-related quality of life, menopause and aging Currently employed menopause-specific quality-of-life scales Quality-of life-measures in practice Conclusions

3. Selected definitions of health and health status Health: –Physical and mental well-being; freedom from disease, pain, or defects; normality of physical and mental functions; soundness –Condition of body or mind [good or bad health]... 1 World Health Organization: Health as a state of complete physical, mental, and social well-being, and not merely the absence of disease or infirmity 2 1 Webster’s Dictionary, 1982; 2 WHO, 1948

4. Selected definitions of health and health status Health: –The state of optimum capacity for the effective performance of valued tasks 1 Illness: –A deviation from the social expectation that a person performs the functions associated with his or her social role 2 Talcott Parsons, 1958; Patrick, Erickson, 1993

5. A definition of health-related quality of life HRQOL –represents those parts of quality of life that directly relate to an individual’s health –includes the domains of physical, psychological, social, spiritual, and role functioning, as well as general well-being Spilker, Revicki, 1996

6. Another definition of health-related quality of life HRQOL –is the value assigned to duration of life as modified by the impairments, functional states, perceptions and social opportunities that are influenced by disease, injury, treatment or policy Patrick, Erickson, 1993

7. Levels of quality of life In their totality, these three levels constitute the scope of quality of life Components of each domain Broad domains Physical, psychological, economic, spiritual, social Overall assessment of well-being Cramer, Spilker, 1998

8. Rationale for using health-related quality-of-life measures Goal of therapy is to make patients feel better Physiological measures may change without people feeling better People may feel better without measurable change in physiological function Trade-offs between treatment effects and side-effects The output of the health-care system is quality- adjusted survival/health-related quality of life. Why not measure it? Guyatt, Feeny, Patrick, 1993

9. Assessment of measures of health-related quality of life Acceptability Burden Reliability Validity Responsiveness Interpretability Usefulness Feeny, et al. 1999

10. Measures of health-related quality of life Generic measures –The MOS 36-Item Short Form Survey (SF-36) 1 –Nottingham Health Profile 2 –Sickness Impact Profile 3 Individualized measures –Patient-Generated Index (PGI) 4 General health and health-related measures –WHO – International Classification of Functioning (ICF) 5 1 Ware, Sherbourne, 1992; 2 McKenna, et al. 1993; 3 Gilson, et al. 1975; 4 Camilleri-Brennan, et al. 2002; 5 WHO, 2001

11. 1 Hunter MS, 1992; 2 Beck, et al. 1961, short version 1969; 3 Zigmond, Snaith, 1983; 4 Feeny D, 2005; 5 Weinstein, et al. 1996 Measures of health-related quality of life Disease- or Population-Specific Measures Women‘s Health Questionnaire (WHQ) 1 Particular Aspect of Health Beck Depression Inventory (BDI) 2 Hospital Anxiety and Depression Scale (HADS) 3 Utility Measures – Health Economics Health Utilities Index (HUI) 4 Cost Effectiveness in Health and Medicine 5

12. Psychometric response scales After the questionnaire is completed, each item may be analyzed separately, or item responses may be summed to create a score for a group of items The Likert Scale is a bipolar scaling method, measuring either positive or negative agreement with a statement Traditionally a 5-point scale; many psychometricians advocate use of 7- or 9- point scales Likert, 1932

13. Psychometric response scales Typical test item in a Likert Scale is a statement A respondent is asked to indicate a degree of agreement with the statement –Strongly disagree –Disagree –Neither agree nor disagree –Agree –Strongly agree

14. Health outcome measures used in published studies A total of 3921 reports Disease- or population-specific46% Generic22% Dimension-specific18% Utility10% Individualized1% During 1990–1999, the number of new reports of development and evaluation rose from 144 to 690 per year Garratt, et al. 2002

15. Most widely used measures within 3921 reports (1) InstrumentNumber of records SF-36 408 Sickness Impact Profile 111 Nottingham Health Profile93 EORTC QLQ-C3082 QALY79 EuroQOL77 Health Assessment Questionnaire 62 Arthritis Impact Measurement Scale 59 Quality of Wellbeing Scale53 General Health Questionnaire43 Health Utilities Index41 COOP Charts33 Functional Assessment of Cancer32

16. Most widely used measures within 3921 reports (2) InstrumentNumber of records WHOQOL 24 Healthy Years Equivalent24 Beck Depression Inventory23 Asthma Quality of Life Questionnaire21 McGill Pain Questionnaire19 WOMAC18 Hospital Anxiety and Depression Scale18 Duke Health Profile17 SF-1215 Psychological General Wellbeing Scale15 St George‘s Respiratory Disease Questionnaire15 MOS-HIV14 Rotterdam Symptom Check List14 Garratt, et al. 2002

17. General measures of quality of life

18. 4Vitality (VT) 2Social functioning (SF) 3Role emotional (RE) 5Mental health (MH) Items (n)Domains 10Physical functioning (PF) 4Role physical (RP) 2Bodily pain (BP) 5General health (GH) Ware, Sherbourne, 1992 SF-36 Measurement Model Summary scales Physical health (PH) Mental health (MH)

19. General health and health-related measures of quality of life

20. The EuroQOL Instrument Mobility I have no problem in walking about I have some problems in walking about I am confined to bed Self-care I have no problems with self-care I have some problems washing or dressing myself I am unable to wash or dress myself Usual activities I have no problems with performing my usual activities (e.g. work, study, housework, family or leisure activities) I have some problems with performing my usual activities I am unable to perform my usual activities Pain/discomfort I have no pain or discomfort I have moderate pain or discomfort I have extreme pain or discomfort Anxiety/depression I am not anxious or depressed I am moderately anxious or depressed I am extremely anxious or depressed Best imaginable health state Worst imaginable health state Kind P, 1996

21. WHOQOL Assessment Domains Physical domain Psychological domain Level of independence Social relationships Environment Spirituality/religion/personal beliefs WHO, 1993

22. Disease- or population-specific measures of quality of life

23. Hospital anxiety and depression scale 7 items on Anxiety; separate score, 0 – 21 7 items on Depression; separate score, 0 – 21 4-point scale for each item (0 – 3) Score of 11 or higher indicates probable case Administration takes 2 – 5 min Sample item: – “I have lost interest in my appearance” Zigmond, Snaith, 1983

24. Health-related quality of life Issues in menopause and aging Vasomotor symptoms Cognitive functioning Vaginal dryness Mood symptoms Urinary complaints Uterine bleeding Sleep Attractiveness Sexual activity Anxiety Depression HRQOL associated with chronic conditions Feeny, 2006

25. Health-related quality of life Issues in menopause and aging Importance of placebo effect in studies on symptoms Lack of standardization of reporting of symptoms Few studies consider HRQOL impact on partner Specific instruments for menopause and aging Generic instrument to capture chronic conditions and side-effects Utility measures to reflect preferences of patients and community Feeny, 2006

26. Currently employed menopause-specific quality-of-life scales (1) Instrument AuthorDomains coveredItems Greene Climacteric Greene, JG PsychologicalList of symptoms Scale (1976, 1998) Somatic Vasomotor Women‘s Health Hunter, M Depressed mood Fully phrased statements Questionnaire (WHQ) (1992, 2006) Somatic symptoms (symptoms and feelings) Vasomotor Anxiety/fears Sexual behavior Sleep problems Menstrual symptoms Memory/concentration Attractiveness QualifemmeFloch, JP ClimactericList of symptoms (1994) Psychosocial Somatic Urogenital The Menopause-Specific Hilditch, TR VasomotorList of symptoms, signs, QOL Questionnaire (1996) Psychosocial feelings (MENQOL)Physical Sexual

27. Currently employed menopause-specific quality-of-life scales (2) Instrument AuthorDomains coveredItems Menopause Rating Schneider, HPGPsychological List of symptoms Scale (MRS) (1996, 2000)Somatovegetative Urogenital Menopausal Symptom Perz, JMPsychological List of symptoms List (MSL) (1997)Vasosomatic General somatic Menopause Quality Jacobs, P, et al.Physical Fully phrased statements of Life Scale (MQOL) (2000)Vasomotor (symptoms and feelings) Psychosocial Sexual Utian Quality of Life Utian, WHOccupational Fully phrased statements Scale (UQOL) (2002)Health-related (symptoms and feelings) Emotional Sexual quality of life

28. Quality-of-life measures in practice

29. Menopause rating scale (MRS) Standardized scale to measure the severity of menopausal symptoms The scale comprises 11 items Symptom intensities range from 0 to 4 –0 – none0–4%* –1 – mild5–24% –2 – moderate25–49% –3 – severe50–95% –4 – complete95–100% * % population with symptoms, according to WHO standards Schneider HPG, et al. 2000

30. 10.8 + 10.6 55.1 + 13.8 32.2 + 9.8 43.9 + 11.8 * Mean values (SD) in four categories of severity at baseline Heinemann, Schneider, 2007 HRT: relative change of the MRS*

31. Comparison between quality-of-life studies Depends on Suitable measure Appropriate selection of population Ethnicity, which varies greatly, –e.g. within Asian cultures 1 1 PAM Study, Limpaphayom et al. 2006

32. LEVELS OF ASSESSMENT Handicap Disability Impairment DOMAINS OF ASSESSMENT TYPE OF MEASUREMENT Physical Mental EmotionalSocial Evaluative Predictive Discriminative Primary purpose of functional assessment Decision of investigators for the appropriate instrument Cramer, Spilker, 1998

33. MEDICAL TREATMENT(S) Safety measures Efficacy measures Additional measures & factors Adverse reactions Clinically beneficial effects Convenience, costs, etc. Patient's values, beliefs, judgements Physical statusPsychologicalSocialEconomic status & abilitieswell-beinginteractions& factors Patient's overall sense of well-being I. Clinical evaluation level III. Quality of life level II. Patient's integration & assessment level Cramer, Spilker, 1998 Clinical aspects, patient's integration and quality of life

34. Conclusions (1) Quality-of-life measures are increasingly used for measuring health outcomes in evaluative research There is evidence of a lack of consistency in the selection of measures for clinical trials which hinders comparison among studies 67 clinical trials were studied, of these, 48 were found to use 62 different existing measures and 13 reported new measures Sanders et al. 1998

35. Conclusions (2) There has been exponential growth in reports relating to the development and evaluation of quality-of-life measures Concurrent evaluation and professional consensus will assist to determine the most suitable measure for a particular application Researchers should undertake comprehensive literature searches to ascertain whether a suitable measure is available before they decide to develop a new one Garratt et al. 2002

36. Addendum

37. Literature Beck AT, Ward CJ, Mendelsohn M, et al. An inventory for measuring depression. Arch Gen Psychiatry 1961;4:561–74 Camilleri-Brennan J, Ruta DA, Steele RJ. Patient generated index: new instrument for measuring quality of life in patients with rectal cancer. World J Surg 2002;26:1354–9 Cramer JA, Spilker B, eds. Quality of Life and Pharmacoeconomics in Clinical Trials – An Introduction. Philadelphia: Lippincott-Raven, 1998 Feeny D, Furlong W, Mulhern RK, et al. A framework for assessing health-related quality of life among children with cancer. Int J Cancer 1999;Suppl 12:2–9 Feeny D. Personal communication, 2006 Feeny D. The Health Utilities Index: A tool for assessing health benefits. PRO Newsletter #34, Spring 2005:2–6 Garratt A, Schmidt L, Mackintosh A, et al. Quality of life measurement: bibliographic study of patient assessed health outcome measures. Br Med J 2002;324:1417 Gilson BS, Gilson JS, Bergner M, et al. The sickness impact profile. Development of an outcome measure of health care. Am J Public Health 1975;65:1304–10 Girod I, de la Loge C, Keininger D, Hunter M. Development of a revised version of the Women's Health Questionnaire. Climacteric 2006;9:4–12 Greene JG. A factor analytic study of climacteric symptoms. J Psychosom Res 1976;20:425–30 Greene JG. Constructing a standard climacteric scale. Maturitas 1998;29:25–31 Guyatt GH, Feeny DH, Patrick DL. Measuring health-related quality of life. Ann Intern Med 1993;118:622–9

38. Literature (2) Heinemann LAJ, Schneider HPG. Quality of life assessment in the menopause. In Eskin BA, ed. The Menopause: Endocrinologic Basis and Management Options, 5th edn. Oxford: Informa Healthcare, 2007:79–85 Hilditch JR, Lewis J, Peter A, et al. A menopause-specific quality of life questionnaire: development and psychometric properties. Maturitas 1996;24:161–75 Hunter MS. The Women's Health Questionnaire (WHQ): a measure of mid-aged women's perceptions of their emotional and physical health. Psychol Health 1992;7:45–54 Jacobs P, Hyland ME, Ley A. Self rated menopausal status and quality of life in women aged 40- 63 years. Br J Health Psych 2000;5:395–411 Kind P. The EuroQoL instrument: an index of health-related quality of life. In Spilker B, ed. QOL and Pharmacoeconomics in Clinical Trials, 2nd edn. Philadelphia: Lippincott-Raven, 1996:191– 201 Le Floch JP, Colau JCI, Zartarian M. Validation d'une méthode d'évaluation de la qualité de vie en ménopause. Refs en Gynécol Obstétr 1994;2:179–88 Likert R. A technique for the measurement of attitudes. Arch Psychol 1932;140:55 Limpaphayom KK, Darmasetiawan MS, Hussain RI, et al. Differential prevalence of quality-of-life categories (domains) in Asian women and changes after therapy with three doses of conjugated estrogens/medroxyprogesterone acetate: the Pan-Asia Menopause (PAM) study. Climacteric 2006;9:204–14

39. Literature (3) McHorney CA, Ware JE, Raczek AE. The MOS 36-item short-form health status survey (SF-36). II. Psychometric and clinical tests of validity in measuring physical and mental health constructs. Med Care 1993;31:247–63 McKenna SP, Hunt SM, Tennant A. The development of a patient-completed index of distress from the Nottingham Health Profile: a new measure for use in cost-utility studies. Br J Med Economics 1993;6:13–24 Parsons T. Definitions of health and illness in light of American values and social structure. In Gartley Jaco E, ed. Patients, Physicians, and Illness. New York: Free Press, 1958:165–87 Patrick DL, Erickson P. Health Status and Health Policy: Quality of Life in Health Care Evaluation and Resource Allocation. New York: Oxford University Press, 1993:22, 61 Perz JM. Development of the menopause symptom list: a factor analytic study of menopause associated symptoms. Women Health 1997;25:53–69 Sanders C, Egger M, Donovan J, et al. Reporting on quality of life in randomised controlled trials: bibliographic study. Br Med J 1998;317:1191–4 Schneider HPG, Hauser GA. The menopause rating scale (MRS II) – clusters of menopausal symptoms. Maturitas 1996;27(Suppl 1):201 Schneider HPG, Heinemann LAJ, Rosemeier HP, et al. The Menopause Rating Scale (MRS): reliability of scores of menopausal complaints. Climacteric 2000;3:59–64

40. Literature (4) Spilker B, Revicki DA. Taxonomy of quality of life. In Spilker B, ed. Quality of Life and Pharmacoeconomics in Clinical Trials, 2nd edn. Philadelphia: Lippincott-Raven, 1996:25–31 Utian WH, Janata JW, Kingsberg SA, et al. The Utian Quality of Life (UQOL) Scale: development and validation of an instrument to quantify quality of life through and beyond menopause. Menopause 2002;9:402–10 Webster’s New World Dictionary of the American Language, Second College Edition. New York: Simon and Schuster, 1982:645 Weinstein MC, Siegel JE, Gold MR, et al. Recommendations of the Panel on Cost-effectiveness in Health and Medicine. JAMA 1996;276:1253–8 World Health Organization. International Classification of Functioning, Disability, and Health. Geneva: WHO, 2001 World Health Organization. Preamble to the Constitution of the World Health Organization. International Health Conference, New York, June 19–July 22, 1946: Report of the US Delegation, Including the Final Act and Related Documents, Department of State publication 2703, Conference Series 91. New York: WHO, 1946, entered into force on 7 April 1948 World Health Organization. WHOQOL study protocol. Geneva: WHO (MNH/PSF/93.9), 1993 Zigmond AS, Snaith RP. The hospital anxiety and depression scale. Acta Psychiatr Scand 1983;67:361–70 Zoellner YF, Acquadro C, Schaefer M. Literature review of instruments to assess health-related quality of life during and after menopause. Qual Life Res 2005;2:309–27

41. Specialties covered by 3921 reports Garratt et al. 2002 Number of records Rheumatology 462 (musculoskeletal) Cancer439 Older people324 Mental health299 Neurological diseases253 General or healthy populations235 Pediatric or adolescent232 Respiratory202 Cardiovascular diseases188 Rehabilitation114 Gastrointestinal diseases100 AIDS90 Proxy71 Urology71 Orthopedics65 Number of records Endocrinology60 Renal53 Dental50 Ophthalmology47 Dermatology39 Carer35 Addiction32 Gynecology29 Mental handicap27 Ear/nose/throat24 Palliative22 Allergy17 Intensive care12 Burns trauma11 Infection11

42. MOS SF-36 Survey: Item Grouping (1) Ware, Sherbourne, 1992 Health ScaleAbbreviated item content Physical functioningVigorous activities, such as running, lifting heavy objects, strenuous sports Moderate activities, such as moving a table, vacuuming, bowling Lifting or carrying groceries Climbing several flights of stairs Climbing one flight of stairs Bending, kneeling, or stooping Walking more than a mile Walking several blocks Walking one block Bathing or dressing yourself Role physicalLimited in the kind of work or other activities Cut down the amount of time spent on work or other activities Accomplished less than would like Difficulty performing the work or other activities Bodily painIntensity of bodily pain Extent pain interfered with normal work

43. MOS SF-36 Survey: Item Grouping (2) Ware, Sherbourne, 1992 Health scaleAbbreviated item content General health perceptionsIs your health: excellent, very good, good, fair, poor My health is excellent I am as healthy as anybody I know I seem to get sick a little easier than other people I expect my health to get worse VitalityFeel full of pep Have a lot of energy Feel worn out Feel tired Social functioningFrequency health problems interfered with social activities Extent health problems interfered with normal social activities Role emotionalCut down the amount of times spent on work or other activities Accomplished less than would like Didn‘t do work or other activities as carefully as usual Mental healthBeen a very nervous person Felt downhearted and blue Felt so down in the dumps nothing could cheer you up Been a happy person Felt calm and peaceful Reported changeRating of health now compared to 1 year ago

44. *5-point scale WHO, Geneva, 1993 WHOQOL domains and facets* Domain I – Physical domain –1 Pain and discomfort –2 Energy and fatigue –3 Sexual activity –4 Sleep and rest –5 Sensory functions Domain II – Psychological domain –6 Positive feelings –7 Thinking, learning, memory, and concentration –8 Self-esteem –9 Body image and appearance –10 Negative feelings Domain III – Level of independence –11 Mobility –12 Activities and daily living –13 Dependence on medical substances and medical aids –14 Dependence on non-medical substances (alcohol, tobacco, drugs) –15 Communication capacity –16 Work capacity Domain IV – Social relationships –17 Personal relationships –18 Practical social support –19 Activities as provider/supporter Domain V – Environment –20 Freedom, physical safety, and security –21 Home environment –22 Work satisfaction –23 Financial resources –24 Health and social care: accessibility and quality –25 Opportunities for acquiring new information and skills –26 Participation in and opportunities for recreation/leisure activities –27 Physical environment (pollution/noise/traffic/climate ) –28 Transport Domain VI – Spirituality/religion/personal beliefs

45. Characteristics of the scales According to Zoellner YF, et al. Qual Life Res 2005;14:309–27 ScaleStructureScoringPsychometric properties ScalingAggregation Greene Climacteric Scale Psychological (P) scale (anxiety 1 to 6; depression 7 to 11): 1. Tachycardia 2. Nervousness 3. Insomnia 4. Being excitable 5. Panic attacks 6. Difficulty concentrating 7. Tired, lack of energy 8. Lost interest in most things 9. Unhappy or depressed 10. Crying spells 11. Irritability Somatic (S) scale 12. Dizzy or faint feelings 13. Pressure, tightness in head, body 14. Parethesia 15. Headaches 16. Arthralgia, myalgia 17. Loss of feeling in hands, feet 18. Breathing difficulties Vasomotor (V) scale 19. Hot flushes 20. Sweating at night "Probe" for sexual dysfunction: 21. Loss of interest in sex 4-point scale Indicate degree to which you are bothered "at the moment" by listed symptoms 0 – not at all 1 – a little 2 – quite a bit 3 – extremely Individual subscale scores Within domain summation of weighted severity scores (weighting factor = 2 if factor loading > 0.50) Will yield three separate scores eventually (P, S, V) Normative data exist from a general population sample (n = 200) of the same age band (40 – 55 years) Reliability Reliability coefficients: P-scale: 0.87 S-scale: 0.84 V-scale: 0.83 Validity Content validity: Only symptoms with statistically significant factor loading (confirmed by other factorial studies, in the latest version) have been included Construct validity: demonstrated in relation to - life stress - bereavement - psychological - treatment - HRT

46. ScaleStructureScoringPsychometric properties ScalingAggregation WHQDomains Depressed mood Somatic symptoms Vasomotor Anxiety/fears Sexual behavior Sleep problems Menstrual symptoms Memory/concentration Attractiveness NB. Symptoms are not listed in blockwise manner to complete one domain and proceed to the next; rather, items from all domains are shuffled across the questionnaire 4-point scale Indicate your agreement with statements as listed : Yes, definitely Yes, sometimes No, not much No, not at all NB. Scoring had to be reversed for some items, as these were phrased positively rather than negatively Within domain only not across domains Overall subscale = mean subscale score Factor scale scores obtained by summing up item scores (within domains only) and dividing by number of items in that domain NB. Some authors sum up all item scores to one global score (min. 0, max. 144) Reliability Test-retest (2 weeks): Correlation between factor scores (scores of same factor at two different points in time) range 0.69 to 0.96 across factors Internal consistency: Assessment not deemed necessary as underlying factor analysis provides sufficient information about item to scale relationship Validity Concurrent validity of psychological scales was estimated by comparison with the 30-item GHQ, correlated 0.81 with depression scale and 0.46 with anxiety scale Characteristics of the scales

47. ScaleStructureScoringPsychometric properties ScalingAggregation MENQOLDomains (items) Physical (16) Vasomotor (3) Psychosocial (10) Sexual (3) Plus general QOL question, which was not included in analysis 7-point scale Indicate how strongly you are bothered by symptoms listed : 0 – not at all 1 – 2 – 3 – 4 – 5 – 6 – extremely Intermediate levels do not carry any description NB. Scoring had to be reversed for some items, as these were phrased positively rather than negatively Within domain only not across domains Overall subscale score = mean subscale score (no weighting) Reliability Test-retest (1 month): Correlation between factor scores (scores of same factor at two different points in time) range between 0.55 and 0.85 across factors Internal consistency: Cronbach‘s alpha ranges between 0.81 and 0.89 Validity Construct validity: Correlation coefficients are computed for both evaluative and discriminative validity and oscillate between 0.40 and 0.65 (discriminative), or 0.28 and 0.60 (evaluative validity) (global QOL item excluded) Characteristics of the scales

48. ScaleStructureScoringPsychometric properties ScalingAggregation MRSDomains (items) Psychological (4) Somatovegetative (4) Urogenital (3) 5-point scale Indicate the severity of symptoms 0 – no symptoms 1 – mild 2 – moderate 3 – marked 4 – severe Within domain only not across domains Overall subscale score = mean subscale score (no weighting) Reliability Test-retest (1.5 years): Correlation between factor scores (scores of same factor at two different points in time) for Severity of scores: K = 0.26 p = 0.000 Somatic symptoms: K = 0.25 p = 0.000 Psychological symptoms: K = 0.30 p = 0.000 Urogenital symptoms: K = 0.19 p = 0.000 Validity By comparison with SF-36 Characteristics of the scales

49. PAM Study Baseline domain scores by ethnic group MENQOL (29) domain (mean  SD) Ethnic origin Number of womenVasomotorPsychosocialPhysicalSexual Chinese2493.13 (1.67)2.84 (1.37)3.21 (1.15)4.04 (2.20) Filipino1993.17 (1.60)3.33 (1.41)3.20 (1.23)3.03 (2.03) Indonesian602.28 (0.87)2.40 (0.68)2.66 (0.63)2.63 (1.18) Korean972.21 (1.40)3.06 (1.46)3.29 (1.24)3.55 (2.29) Malay243.02 (1.56)2.78 (1.11)2.93 (1.08)3.14 (1.78) Pakistani604.96 (2.41)4.24 (1.64)4.84 (1.61)2.90 (1.70) Taiwanese812.29 (1.39)2.37 (1.32)2.84 (1.23)2.11 (1.32) Thai1502.87 (1.61)3.10 (1.22)3.28 (1.08)2.89 (1.90) Vietnamese1005.71 (1.59)5.96 (1.48)5.39 (1.20)6.55 (1.67) Limpaphayom, et al. 2006