ORIGINAL ARTICLE
How Healthy Is the Singaporean Worker? Results From the Singapore National Health Survey 2010 Raymond Boon Tar Lim, MBBS, MPH, Stefan Ma, MSc, PhD, Chee Weng Fong, MSc, Lily Chua, MSc, Kee Seng Chia, MBBS, MSc(OM), MD, Derrick Heng, MBBS, MSc, and Wei Yen Lim, MBBS, MPH, PhD
Objective: To compare the prevalence of common medical conditions (including mental health and self-rated health) and lifestyle risk factors for disease of the Singapore workforce with the nonworking population, and evaluate the association of these factors with occupation class. Methods: Data were obtained from a population-representative cross-sectional survey in 2010. Adjusted prevalence ratios (PRs) were obtained by modified Breslow-Cox proportional hazards regression model. Results: Within the workforce, after adjustment for age, sex, and ethnicity, daily smoking (PR = 1.87; 95% confidence interval [CI], 1.40 to 2.51; P < 0.001), no regular exercise (PR = 1.13; 95% CI, 1.07 to 1.20; P < 0.001), and poor self-rated health (PR = 1.46, 95% CI, 1.22 to 1.76; P < 0.001) were more prevalent in the lower-skilled occupation classes. Conclusions: Lower-skilled occupation classes in Singapore are associated with lifestyle risk factors, and tailored workplace health promotion programs addressing their specific health needs are needed.
T
here is evidence that the burden of chronic diseases and their risk factors is increasing globally.1 A projected 388 million people will die of chronic diseases in the next 10 years; most of these deaths will occur in the most productive ages of 15 to 64 years,2 meaning that a substantial portion of the burden occurs in the working-age population globally. In Singapore, 10% of all deaths in 2012 were workers. Among these workers, more than one third (35%) died of heart and hypertensive diseases. Close to one fifth (18%) died of cancer.3 Although the “healthy worker” effect means that those who are employed tend to have a more favorable disease morbidity and mortality pattern than the general population, recent evidence has suggested that the disease burden in the working population is growing. Health Director Dame Carol Black’s call for a healthier working population in the United Kingdom4 and the release of the Milken Institute report on the economic burden of chronic diseases5 in the United States have both highlighted that chronic diseases are widely prevalent in the working-age population. In 2003, the United Kingdom incurred production losses due to cardiovascular diseases mortality (£3.7 billion) and morbidity (£2.6 billion) in those of working age.6 In Australia, from 1998 to 2001, two thirds of the workers reported long-term conditions; and 1 in 10 workers rated their health as poor.7 Lifestyle risk factors and poor mental health are also common in the working population. The first German National Health Survey (NHS) from 1997 to 1999 showed that 40% of the working From the Saw Swee Hock School of Public Health (Drs Lim, Chia, and Lim), National University of Singapore; and Public Health Group (Drs Ma and Heng, Mr Fong, and Ms Chua), Ministry of Health Singapore. The National Health Survey is part of the Ministry of Health’s ongoing surveillance of the health status of Singaporeans. The authors declared no competing interests. Address correspondence to Raymond Boon Tar Lim, MBBS, MPH, Saw Swee Hock School of Public Health, National University of Singapore, MD3, 16 Medical Dr, Singapore 117597 ([email protected]). C 2014 by American College of Occupational and Environmental Copyright Medicine DOI: 10.1097/JOM.0000000000000131
498
population did not engage in physical activity.8 In the United States, 29% of the workforce in 1999 to 2000 was obese; an increase of 20% compared with a decade ago.9 The European Mental Health Agenda estimated that 20% of the European Union working population has some type of mental health problem at any given time,10 while the Canadian Community Health Survey reported that 11% of the working population had at least one mental disorder.11 More than 1 billion people are employed in the world, of which more than half are from Asia,12 yet there is paucity of information on the health of Asian working populations. Singapore is a multiethnic country located in South-East Asia, with people of Chinese, Malays, and Indian ethnicities, and has undergone rapid economic and demographic transitions over the last 40 years.13 The aim of this article was to compare the prevalence of common chronic medical conditions (such as diabetes mellitus, hypertension, and hyperlipidemia) and lifestyle factors, both of which are known risk factors for major cardiovascular diseases such as coronary heart disease and stroke, between the working and nonworking populations of Singapore, and to evaluate whether these vary by occupation classes.
METHODS Data for this study were drawn from the NHS conducted in 2010. The NHS is a national representative cross-sectional survey conducted every 6 years by the Ministry of Health to determine the current prevalence of chronic diseases and their risk factors in Singapore. The study design of the NHS has been published.14 Briefly, a two-stage stratified sampling method was used. In the first stage, a probability sample of household addresses was selected from a household sampling frame maintained by the Department of Statistics to enumerate eligible individuals. In the second stage, a random sample was selected from the frame of eligible individuals living in those households. Eligible individuals were community-dwelling Singapore residents aged 18 to 79 years. A total of 4337 persons of an eventual sample of 7512 eligible Singapore residents took part in the survey, yielding an overall response rate of 57.7% (Fig. 1). Sample weights were calculated for both the household enumeration exercise and survey fieldwork. For both stages, sample weights comprise weights for unequal selection probabilities and adjustment for variation in nonresponse rates. Poststratification weights were also computed on the basis of the characteristics of the 2010 Census population. The overall sample weights were the product of household enumeration exercise sample weights, survey fieldwork sample weights, and the poststratification weights. An ethics review of this study was conducted by an institutional review board (convened by the Health Promotion Board, Singapore) before study implementation. Survey respondents underwent a health screening and answered a questionnaire in a structured interview administered by trained nurses at designated survey centers. The questionnaire included questions on common chronic diseases, lifestyle risk factors, mental health, as well as self-rated health. For the purpose of this study, we limit our analysis to Singapore residents of the three major ethnic groups (Chinese, Malays, and Indians) from 18 to 69 years of age (3703 participants as shown in JOEM r Volume 56, Number 5, May 2014
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
JOEM r Volume 56, Number 5, May 2014
Health of the Singapore Workforce
Households addresses were selected based on a modified two-stage design* (n=47,500 addresses) Incorporang ethnicity informaon on household members residing at the addresses Household addresses randomly selected (n=17,000 /47,500 addresses)
Enrollment
Household enumeraon exercise
Total number of individuals randomly selected from the enumerated households (n=7,695 individuals) Ineligible (n= 183 individuals) due to reasons such as pregnancy, instuonalised (in hospital, nursing home, prison), death and overseas during survey period Total number of eligible individuals (n=7,512/7,695 individuals) Non-respondents (n= 3,175) Overall response rate: 57.7% Individuals who completed the survey (n=4,337 out of 7,512 eligible individuals) Excluded (n= 634 individuals) due to age 70-79 years and from ethnicies other than Chinese, Malays and Indians
Analysis
Analysed (n=3,703)
Working populaon (n=2,613)
Non-working populaon (n=1,090)
*During the first stage selecon, geographical zones (primary sampling units, PSUs) within three to five kilometres of the six survey sites were selected. For the second stage selecon, a fixed number of dwelling units was selected using simple random sampling without replacement proporonally from defined broad dwelling type groups within each selected PSUs from the first stage of sample selecon.
FIGURE 1. Flow diagram of participants analyzed for this study derived from the National Health Survey 2010.
Fig. 1), because they made up more than 96% of the total resident population; the other minority groups such as Eurasians are excluded because of small numbers (less than 4% of the total population).15 Statistical analyses were performed using STATA version 11.2 (Stata Corp, College Station, TX). The definitions of the common chronic medical conditions (including mental health and self-rated health) and the lifestyle risk factors used for this study are summarized in Table 1.16–23 In addition, the working population was defined as any Singapore resident hold-
ing a current occupation (including those who were self-employed) at the time of survey. Occupations were classified according to the 10 major classes of the International Standard Classification of Occupations 2008 by the International Labour Organization24 and further grouped into 4 classes according to the skill level and specialization required for each occupation. The highest-skilled occupation class (level 4) typically include occupations in which job tasks require complex problem solving, decision making, and creativity based on theoretical and factual knowledge in a specialized field; whereas
C 2014 American College of Occupational and Environmental Medicine
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
499
JOEM r Volume 56, Number 5, May 2014
Lim et al
TABLE 1. Definitions of Medical Conditions (Including Mental Health and Self-Rated Health) and Lifestyle Risk Factors for Disease Used in This Study Medical Condition/ Lifestyle Risk Factor Medical conditions Diabetes mellitus
Criteria Used
Type of Data (Including Questions and Response Options if Self-Reported Data)
Positive oral glucose tolerance test
Objective biological measurement
Hypertension
WHO classification criteria16 for hypertension and the standards prescribed in the WHO MONICA Protocol17 for measurement of blood pressure was used
Objective biological measurement
Hyperlipidemia
MOH’s Clinical Practice Guidelines on Lipids 200118 12-item GHQ
Objective biological measurement
Poor mental health
Self-reported Questions: Have you recently (in the past 6 weeks): 1. Been able to concentrate on whatever you’re doing? a. Better than usual (0) b. Same as usual (0) c. Less than usual (1) d. Much less than usual (1) 2. Lost much sleep over worry? a. Not at all (0) b. No more than usual (0) c. Rather more than usual (1) d. Much more than usual (1) 3. Felt that you are playing a useful part in things? a. More so than usual (0) b. Same as usual (0) c. Less useful than usual (1) d. Much less useful (1) 4. Felt capable of making decisions about things? a. More so than usual (0) b. Same as usual (0) c. Less so than usual (1) d. Much less capable (1) 5. Felt constantly under strain? a. Not at all (0) b. No more than usual (0) c. Rather more than usual (1) d. Much more than usual (1) 6. Felt you couldn’t overcome your difficulties? a. Not at all (0) b. No more than usual (0) c. Rather more than usual (1) d. Much more than usual (1)
Definition of Positive Medical Condition/Lifestyle Risk Factor
Oral glucose tolerance test: 2-hr plasma glucose concentration of ≥11.1 mmol/I or ≥200mg/dI, as well as respondents with the known disease previously diagnosed by a doctor and currently on medication Measured systolic blood pressure of ≥140 mm Hg or diastolic blood pressure of ≥90 mm Hg, as well as respondents with the known disease previously diagnosed by a doctor and currently on medication Fasting total cholesterol ≥6.2 mmol/I or ≥240 mg/dI Participants with GHQ total score of at least 2 was classified as poor mental health according to the cutoff used by a published study in the Singapore population19
(continued )
500
C 2014 American College of Occupational and Environmental Medicine
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
JOEM r Volume 56, Number 5, May 2014
Health of the Singapore Workforce
TABLE 1. (Continued ) Medical Condition/ Lifestyle Risk Factor
Poor self-rated health
Criteria Used
—
Type of Data (Including Questions and Response Options if Self-Reported Data) 7. Been able to enjoy your normal day-to-day activities? a. Better than usual (0) b. Same as usual (0) c. Less than usual (1) d. Much less than usual (1) 8. Been able to face up to your problems? a. More so than usual (0) b. Same as usual (0) c. Less so than usual (1) d. Much less capable (1) 9. Been feeling unhappy and depressed? a. Not at all (0) b. No more than usual (0) c. Rather more than usual (1) d. Much more than usual (1) 10. Been losing confidence in yourself? a. Not at all (0) b. No more than usual (0) c. Rather more than usual (1) d. much more than usual (1) 11. Been thinking of yourself as a worthless person? a. Not at all (0) b. No more than usual (0) c. Rather more than usual (1) d. Much more than usual (1) 12. Been feeling reasonably happy, all things considered? a. Better than usual (0) b. Same as usual (0) c. Less than usual (1) d. Much less than usual (1) Range of GHQ total score from 0 (minimum) to 12 (maximum) Self-reported Question 1. In general, how would you rate your health today? a. Very good b. Good c. Moderate d. Bad e. Very bad f. Refused g. Don’t know
Lifestyle risk factors Obesity Daily smoking
WHO International classification of weight status21 WHO classification criteria for cigarette smoking status22
Definition of Positive Medical Condition/Lifestyle Risk Factor
Participants who rated their overall health to be moderate, bad or very bad according to the cutoff used by a published study in the Singapore population was classified as having poor self-rated health20
Objective biological measurement
Body mass index ≥ 30 kg/m2
Self-reported
Smoked cigarettes at least once a day, including people who smoke everyday but have to stop temporarily because of religious fasting or medical reasons) (continued )
C 2014 American College of Occupational and Environmental Medicine
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
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JOEM r Volume 56, Number 5, May 2014
Lim et al
TABLE 1. (Continued ) Medical Condition/ Lifestyle Risk Factor
Regular drinker
Criteria Used
—
Binge drinking
—
No regular exercise
American College of Sports Medicine’s classification23
Type of Data (Including Questions and Response Options if Self-Reported Data) Questions 1. Have you ever smoked cigarettes? a. Yes b. No 2. Have you ever smoked at least 100 cigarettes (about 5 packs) in your whole life? a. Yes b. No 3. Have you ever smoked cigarettes daily? a. Yes b. No 4. Do you smoke now? a. Daily b. Occasionally c. Have stopped smoking completely Self-reported Questions 1. Have you ever consumed alcohol? a. Yes b. No 2. Have you consumed alcohol within the past 12 months? a. Yes b. No 3. In the past 12 months, how frequently have you had at least one drink? a. 5 or more days a week b. 1–4 days per week c. 1–3 days a month d. Less than once a month Self-reported Question During the past month, have you ever had X (X = 5 for men, X = 4 for women) or more (all types of alcoholic drinks) in any one drinking session? a. Yes b. No Self-reported Questions 1. In the past 3 months, did you participate in any sports, exercise, or walking during your leisure time? a. Yes b. No
Definition of Positive Medical Condition/Lifestyle Risk Factor Participants who answered “yes” to questions 1 to 3 and “daily” to question 4 were classified as daily smoking
Alcohol consumption of 5 or more days a week Participants who answered “yes” to questions 1 and 2 as well as “5 or more days a week” to question 3 were classified as regular drinker
Consumption of five or more alcoholic drinks* for men or four or more alcoholic drinks for women in any one drinking session during the past month preceding the survey Participants who answered “yes” to the question were classified as having binge drinking Not participating in any form of sports or exercise for at least 20 minutes per occasion, for 3 or more days a week Participants with the sum of questions 3 and 6
How Healthy Is the Singaporean Worker? Results From the Singapore National Health Survey 2010 Raymond Boon Tar Lim, MBBS, MPH, Stefan Ma, MSc, PhD, Chee Weng Fong, MSc, Lily Chua, MSc, Kee Seng Chia, MBBS, MSc(OM), MD, Derrick Heng, MBBS, MSc, and Wei Yen Lim, MBBS, MPH, PhD
Objective: To compare the prevalence of common medical conditions (including mental health and self-rated health) and lifestyle risk factors for disease of the Singapore workforce with the nonworking population, and evaluate the association of these factors with occupation class. Methods: Data were obtained from a population-representative cross-sectional survey in 2010. Adjusted prevalence ratios (PRs) were obtained by modified Breslow-Cox proportional hazards regression model. Results: Within the workforce, after adjustment for age, sex, and ethnicity, daily smoking (PR = 1.87; 95% confidence interval [CI], 1.40 to 2.51; P < 0.001), no regular exercise (PR = 1.13; 95% CI, 1.07 to 1.20; P < 0.001), and poor self-rated health (PR = 1.46, 95% CI, 1.22 to 1.76; P < 0.001) were more prevalent in the lower-skilled occupation classes. Conclusions: Lower-skilled occupation classes in Singapore are associated with lifestyle risk factors, and tailored workplace health promotion programs addressing their specific health needs are needed.
T
here is evidence that the burden of chronic diseases and their risk factors is increasing globally.1 A projected 388 million people will die of chronic diseases in the next 10 years; most of these deaths will occur in the most productive ages of 15 to 64 years,2 meaning that a substantial portion of the burden occurs in the working-age population globally. In Singapore, 10% of all deaths in 2012 were workers. Among these workers, more than one third (35%) died of heart and hypertensive diseases. Close to one fifth (18%) died of cancer.3 Although the “healthy worker” effect means that those who are employed tend to have a more favorable disease morbidity and mortality pattern than the general population, recent evidence has suggested that the disease burden in the working population is growing. Health Director Dame Carol Black’s call for a healthier working population in the United Kingdom4 and the release of the Milken Institute report on the economic burden of chronic diseases5 in the United States have both highlighted that chronic diseases are widely prevalent in the working-age population. In 2003, the United Kingdom incurred production losses due to cardiovascular diseases mortality (£3.7 billion) and morbidity (£2.6 billion) in those of working age.6 In Australia, from 1998 to 2001, two thirds of the workers reported long-term conditions; and 1 in 10 workers rated their health as poor.7 Lifestyle risk factors and poor mental health are also common in the working population. The first German National Health Survey (NHS) from 1997 to 1999 showed that 40% of the working From the Saw Swee Hock School of Public Health (Drs Lim, Chia, and Lim), National University of Singapore; and Public Health Group (Drs Ma and Heng, Mr Fong, and Ms Chua), Ministry of Health Singapore. The National Health Survey is part of the Ministry of Health’s ongoing surveillance of the health status of Singaporeans. The authors declared no competing interests. Address correspondence to Raymond Boon Tar Lim, MBBS, MPH, Saw Swee Hock School of Public Health, National University of Singapore, MD3, 16 Medical Dr, Singapore 117597 ([email protected]). C 2014 by American College of Occupational and Environmental Copyright Medicine DOI: 10.1097/JOM.0000000000000131
498
population did not engage in physical activity.8 In the United States, 29% of the workforce in 1999 to 2000 was obese; an increase of 20% compared with a decade ago.9 The European Mental Health Agenda estimated that 20% of the European Union working population has some type of mental health problem at any given time,10 while the Canadian Community Health Survey reported that 11% of the working population had at least one mental disorder.11 More than 1 billion people are employed in the world, of which more than half are from Asia,12 yet there is paucity of information on the health of Asian working populations. Singapore is a multiethnic country located in South-East Asia, with people of Chinese, Malays, and Indian ethnicities, and has undergone rapid economic and demographic transitions over the last 40 years.13 The aim of this article was to compare the prevalence of common chronic medical conditions (such as diabetes mellitus, hypertension, and hyperlipidemia) and lifestyle factors, both of which are known risk factors for major cardiovascular diseases such as coronary heart disease and stroke, between the working and nonworking populations of Singapore, and to evaluate whether these vary by occupation classes.
METHODS Data for this study were drawn from the NHS conducted in 2010. The NHS is a national representative cross-sectional survey conducted every 6 years by the Ministry of Health to determine the current prevalence of chronic diseases and their risk factors in Singapore. The study design of the NHS has been published.14 Briefly, a two-stage stratified sampling method was used. In the first stage, a probability sample of household addresses was selected from a household sampling frame maintained by the Department of Statistics to enumerate eligible individuals. In the second stage, a random sample was selected from the frame of eligible individuals living in those households. Eligible individuals were community-dwelling Singapore residents aged 18 to 79 years. A total of 4337 persons of an eventual sample of 7512 eligible Singapore residents took part in the survey, yielding an overall response rate of 57.7% (Fig. 1). Sample weights were calculated for both the household enumeration exercise and survey fieldwork. For both stages, sample weights comprise weights for unequal selection probabilities and adjustment for variation in nonresponse rates. Poststratification weights were also computed on the basis of the characteristics of the 2010 Census population. The overall sample weights were the product of household enumeration exercise sample weights, survey fieldwork sample weights, and the poststratification weights. An ethics review of this study was conducted by an institutional review board (convened by the Health Promotion Board, Singapore) before study implementation. Survey respondents underwent a health screening and answered a questionnaire in a structured interview administered by trained nurses at designated survey centers. The questionnaire included questions on common chronic diseases, lifestyle risk factors, mental health, as well as self-rated health. For the purpose of this study, we limit our analysis to Singapore residents of the three major ethnic groups (Chinese, Malays, and Indians) from 18 to 69 years of age (3703 participants as shown in JOEM r Volume 56, Number 5, May 2014
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
JOEM r Volume 56, Number 5, May 2014
Health of the Singapore Workforce
Households addresses were selected based on a modified two-stage design* (n=47,500 addresses) Incorporang ethnicity informaon on household members residing at the addresses Household addresses randomly selected (n=17,000 /47,500 addresses)
Enrollment
Household enumeraon exercise
Total number of individuals randomly selected from the enumerated households (n=7,695 individuals) Ineligible (n= 183 individuals) due to reasons such as pregnancy, instuonalised (in hospital, nursing home, prison), death and overseas during survey period Total number of eligible individuals (n=7,512/7,695 individuals) Non-respondents (n= 3,175) Overall response rate: 57.7% Individuals who completed the survey (n=4,337 out of 7,512 eligible individuals) Excluded (n= 634 individuals) due to age 70-79 years and from ethnicies other than Chinese, Malays and Indians
Analysis
Analysed (n=3,703)
Working populaon (n=2,613)
Non-working populaon (n=1,090)
*During the first stage selecon, geographical zones (primary sampling units, PSUs) within three to five kilometres of the six survey sites were selected. For the second stage selecon, a fixed number of dwelling units was selected using simple random sampling without replacement proporonally from defined broad dwelling type groups within each selected PSUs from the first stage of sample selecon.
FIGURE 1. Flow diagram of participants analyzed for this study derived from the National Health Survey 2010.
Fig. 1), because they made up more than 96% of the total resident population; the other minority groups such as Eurasians are excluded because of small numbers (less than 4% of the total population).15 Statistical analyses were performed using STATA version 11.2 (Stata Corp, College Station, TX). The definitions of the common chronic medical conditions (including mental health and self-rated health) and the lifestyle risk factors used for this study are summarized in Table 1.16–23 In addition, the working population was defined as any Singapore resident hold-
ing a current occupation (including those who were self-employed) at the time of survey. Occupations were classified according to the 10 major classes of the International Standard Classification of Occupations 2008 by the International Labour Organization24 and further grouped into 4 classes according to the skill level and specialization required for each occupation. The highest-skilled occupation class (level 4) typically include occupations in which job tasks require complex problem solving, decision making, and creativity based on theoretical and factual knowledge in a specialized field; whereas
C 2014 American College of Occupational and Environmental Medicine
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
499
JOEM r Volume 56, Number 5, May 2014
Lim et al
TABLE 1. Definitions of Medical Conditions (Including Mental Health and Self-Rated Health) and Lifestyle Risk Factors for Disease Used in This Study Medical Condition/ Lifestyle Risk Factor Medical conditions Diabetes mellitus
Criteria Used
Type of Data (Including Questions and Response Options if Self-Reported Data)
Positive oral glucose tolerance test
Objective biological measurement
Hypertension
WHO classification criteria16 for hypertension and the standards prescribed in the WHO MONICA Protocol17 for measurement of blood pressure was used
Objective biological measurement
Hyperlipidemia
MOH’s Clinical Practice Guidelines on Lipids 200118 12-item GHQ
Objective biological measurement
Poor mental health
Self-reported Questions: Have you recently (in the past 6 weeks): 1. Been able to concentrate on whatever you’re doing? a. Better than usual (0) b. Same as usual (0) c. Less than usual (1) d. Much less than usual (1) 2. Lost much sleep over worry? a. Not at all (0) b. No more than usual (0) c. Rather more than usual (1) d. Much more than usual (1) 3. Felt that you are playing a useful part in things? a. More so than usual (0) b. Same as usual (0) c. Less useful than usual (1) d. Much less useful (1) 4. Felt capable of making decisions about things? a. More so than usual (0) b. Same as usual (0) c. Less so than usual (1) d. Much less capable (1) 5. Felt constantly under strain? a. Not at all (0) b. No more than usual (0) c. Rather more than usual (1) d. Much more than usual (1) 6. Felt you couldn’t overcome your difficulties? a. Not at all (0) b. No more than usual (0) c. Rather more than usual (1) d. Much more than usual (1)
Definition of Positive Medical Condition/Lifestyle Risk Factor
Oral glucose tolerance test: 2-hr plasma glucose concentration of ≥11.1 mmol/I or ≥200mg/dI, as well as respondents with the known disease previously diagnosed by a doctor and currently on medication Measured systolic blood pressure of ≥140 mm Hg or diastolic blood pressure of ≥90 mm Hg, as well as respondents with the known disease previously diagnosed by a doctor and currently on medication Fasting total cholesterol ≥6.2 mmol/I or ≥240 mg/dI Participants with GHQ total score of at least 2 was classified as poor mental health according to the cutoff used by a published study in the Singapore population19
(continued )
500
C 2014 American College of Occupational and Environmental Medicine
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
JOEM r Volume 56, Number 5, May 2014
Health of the Singapore Workforce
TABLE 1. (Continued ) Medical Condition/ Lifestyle Risk Factor
Poor self-rated health
Criteria Used
—
Type of Data (Including Questions and Response Options if Self-Reported Data) 7. Been able to enjoy your normal day-to-day activities? a. Better than usual (0) b. Same as usual (0) c. Less than usual (1) d. Much less than usual (1) 8. Been able to face up to your problems? a. More so than usual (0) b. Same as usual (0) c. Less so than usual (1) d. Much less capable (1) 9. Been feeling unhappy and depressed? a. Not at all (0) b. No more than usual (0) c. Rather more than usual (1) d. Much more than usual (1) 10. Been losing confidence in yourself? a. Not at all (0) b. No more than usual (0) c. Rather more than usual (1) d. much more than usual (1) 11. Been thinking of yourself as a worthless person? a. Not at all (0) b. No more than usual (0) c. Rather more than usual (1) d. Much more than usual (1) 12. Been feeling reasonably happy, all things considered? a. Better than usual (0) b. Same as usual (0) c. Less than usual (1) d. Much less than usual (1) Range of GHQ total score from 0 (minimum) to 12 (maximum) Self-reported Question 1. In general, how would you rate your health today? a. Very good b. Good c. Moderate d. Bad e. Very bad f. Refused g. Don’t know
Lifestyle risk factors Obesity Daily smoking
WHO International classification of weight status21 WHO classification criteria for cigarette smoking status22
Definition of Positive Medical Condition/Lifestyle Risk Factor
Participants who rated their overall health to be moderate, bad or very bad according to the cutoff used by a published study in the Singapore population was classified as having poor self-rated health20
Objective biological measurement
Body mass index ≥ 30 kg/m2
Self-reported
Smoked cigarettes at least once a day, including people who smoke everyday but have to stop temporarily because of religious fasting or medical reasons) (continued )
C 2014 American College of Occupational and Environmental Medicine
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
501
JOEM r Volume 56, Number 5, May 2014
Lim et al
TABLE 1. (Continued ) Medical Condition/ Lifestyle Risk Factor
Regular drinker
Criteria Used
—
Binge drinking
—
No regular exercise
American College of Sports Medicine’s classification23
Type of Data (Including Questions and Response Options if Self-Reported Data) Questions 1. Have you ever smoked cigarettes? a. Yes b. No 2. Have you ever smoked at least 100 cigarettes (about 5 packs) in your whole life? a. Yes b. No 3. Have you ever smoked cigarettes daily? a. Yes b. No 4. Do you smoke now? a. Daily b. Occasionally c. Have stopped smoking completely Self-reported Questions 1. Have you ever consumed alcohol? a. Yes b. No 2. Have you consumed alcohol within the past 12 months? a. Yes b. No 3. In the past 12 months, how frequently have you had at least one drink? a. 5 or more days a week b. 1–4 days per week c. 1–3 days a month d. Less than once a month Self-reported Question During the past month, have you ever had X (X = 5 for men, X = 4 for women) or more (all types of alcoholic drinks) in any one drinking session? a. Yes b. No Self-reported Questions 1. In the past 3 months, did you participate in any sports, exercise, or walking during your leisure time? a. Yes b. No
Definition of Positive Medical Condition/Lifestyle Risk Factor Participants who answered “yes” to questions 1 to 3 and “daily” to question 4 were classified as daily smoking
Alcohol consumption of 5 or more days a week Participants who answered “yes” to questions 1 and 2 as well as “5 or more days a week” to question 3 were classified as regular drinker
Consumption of five or more alcoholic drinks* for men or four or more alcoholic drinks for women in any one drinking session during the past month preceding the survey Participants who answered “yes” to the question were classified as having binge drinking Not participating in any form of sports or exercise for at least 20 minutes per occasion, for 3 or more days a week Participants with the sum of questions 3 and 6
