EUROPEAN JOURNAL OF PUBLIC HEALTH 2003; 13: 171–176
Knowledge and attitudes of economically disadvantaged women regarding exposure to environmental tobacco smoke A Michigan, USA study MARGOT E. KURTZ, J.C. KURTZ, DAWN CONTRERAS, CHERYL BOOTH *
Background: Exposure to environmental tobacco smoke (ETS) is a global public health problem which is particularly acute in groups where smoking rates are higher than in the general population. A study was undertaken to investigate knowledge, attitudes and preventive efforts with regard to exposure to ETS in a sample of economically disadvantaged women residing in Michigan, USA. Methods: Analysis-of-variance techniques were used to investigate how knowledge, attitudes and preventive efforts regarding exposure to ETS relate to demographic variables such as smoking status, ethnicity, education, employment, and income; and analysis-of-covariance techniques were applied to determine the degree to which knowledge, attitudes, age, smoking status, ethnicity, education, employment, income and home environment predict these women’s preventive efforts regarding exposure to ETS. Results: Generally, women with no high school diploma and women who were smokers were less knowledgeable about the adverse health effects of exposure to ETS, had worse attitudes concerning exposure to ETS and were less likely to take preventive steps to limit their exposure to ETS than were women who had more formal education or who were nonsmokers, respectively. The primary predictors of preventive efforts were knowledge, attitudes and smoking status. Conclusions: The results suggest that educational efforts focusing on increasing knowledge and improving attitudes regarding exposure to ETS, as well as providing practical strategies for limiting exposure to ETS, should be developed and delivered to at-risk populations. Keywords: attitudes, environmental tobacco smoke, ETS, knowledge, passive smoking, second-hand smoke
E
xposure to environmental tobacco smoke (ETS) is a global public health issue. The United States Environmental Protection Agency (EPA) has concluded that widespread exposure to environmental tobacco smoke (ETS) represents a serious and substantial health risk, and has classified ETS as a group A carcinogen causing cancer in humans.1 Some progress has been made in the United States to address this issue with the introduction of legislation providing for smoke-free environments, and some similar progress has been made recently in Australia.2 However, many countries in the European Union have been slower in introducing such measures, despite the fact that smoking rates in many of these countries are substantially higher than smoking rates in the United States (e.g. United States 23.5%, Germany 37%, France 33%, Denmark 31%).3,4 Public smoking bans not only reduce exposure of the public to ETS, but have also been shown to have the additional positive effect of encouraging * M.E. Kurtz1, J.C. Kurtz2, D. Contreras3, C. Booth3 1 Department of Family and Community Medicine, Michigan State University, East Lansing, USA 2 Department of Mathematics, Michigan State University, East Lansing, USA 3 Michigan State University Extension, East Lansing, USA Correspondence: Margot E. Kurtz, PhD, Professor, Department of Family and Community Medicine, Michigan State University, B211 West Fee Hall, East Lansing, MI 48824 USA, tel. +1 517 353 4732, fax +1 517 353 6613, e-mail:
[email protected]
quitting and reducing consumption among those who continue smoking.5,6 In the United States, three landmark reports have concluded that exposure to ETS does cause lung cancer and other diseases.7–9 Much earlier, Hirayama10 established that wives of heavy smokers had a higher risk of developing lung cancer than those of nonsmokers, and wives of men who smoked more than 20 cigarettes per day were more than twice as likely to die from lung cancer than those married to nonsmokers. Since then considerable epidemiological evidence has accumulated which suggests that long-term exposure to ETS increases the risk for developing various cancers, and most of all lung cancer.11–15 Also associated with exposure to ETS are ischemic heart disease,16,17 stroke and peripheral vascular disease18 and respiratory disease.19 Glantz and Parmley20 assert that exposure to ETS is the third leading cause of premature death and disability in the United States. A recent European epidemiological study conducted by the International Agency for Research on Cancer21 reported a 16% increase in risk of lung cancer for nonsmoking spouses of smokers. The tobacco industry has been working hard to undermine this study in particular, and has systematically attempted to confuse the evidence around the health impact of ETS, thus undermining 171 public education campaigns on ETS.22,23
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The adverse effects of smoking by pregnant women during the course of pregnancy and delivery as well as post-natal development have been thoroughly investigated.24–26 Smoking during pregnancy not only affects birth height and birth weight, but impairs the subsequent growth of these children.27 In addition, a relationship between smoking by the mother during pregnancy and cancer risk in the offspring has been identified,28 although it has not been clearly differentiated whether smoke exposure during pregnancy or passive smoking of the neonate infant is responsible for some of these effects. A relationship between sudden infant death and exposure to ETS in infancy has also been reported.29,30 Children are indeed the passive victims of the effects of tobacco smoke from their surrounding environments. Parental smoking and smoking by other household members have been associated with respiratory infections, decreased lung function, middle ear effusions, and learning disabilities in children and infants.31–33 An increased severity of symptoms has also been noted for children with asthma.34,35 Major efforts have been devoted to education on the adverse effects of smoking, and to smoking cessation programmes. In contrast, the very real and significant health consequences of exposure to ETS, as well as the knowledge and attitudes of the general public regarding the dangers of exposure to ETS, have received much less attention from researchers, public health educators and the media. Some recent studies36–39 have examined knowledge, attitudes and preventive efforts towards ETS of children, adolescents and college students and some adult populations, but few studies have dealt with knowledge and attitudes about exposure to ETS among highrisk groups such as persons of lower socioeconomic status,40 which usually exhibit higher smoking rates than the general population. This study focused on knowledge, attitudes and preventive efforts towards exposure to ETS of economically disadvantaged women from the State of Michigan, USA, where smoking rates of adults (25.6%) are higher than in the rest of the nation (23.5%), and among adults with no more than 12 years of formal education, rates are even higher (30.6%).41 The following research questions were investigated: What knowledge and attitudes do the women have regarding exposure to environmental tobacco smoke, and what preventive efforts do they take? How do the women’s knowledge, attitudes and preventive efforts regarding exposure to ETS relate to demographic variables such as smoking status, ethnicity, education, employment, and income? To what degree do variables such as knowledge, attitudes, age, smoking status, ethnicity, education, employment, income and home environment predict the women’s preventive efforts regarding exposure to ETS? METHODS
Sample The sample for this study consisted of 180 economically 172 disadvantaged women residing in five counties located in
the State of Michigan, USA, who participated in a university extension programme where they received education in the areas of nutrition and resource management. Women receiving public assistance in a given county were contacted by the university extension service and invited to participate in the extension programme. Economically disadvantaged in this context means the women had incomes below the official poverty level and were receiving some type of public financial assistance. For a family of three, the poverty level is defined as $12,278 per year. The five counties were selected to include a representative mix of urban, suburban and rural communities. Within the five selected counties, all participants in the education sessions were invited to join the study. No refusals were received. Instrumentation A structured, written questionnaire assessing knowledge of the health effects of exposure to ETS, attitudes towards exposure to ETS, and preventive efforts taken to avoid or minimize exposure to ETS was designed, based on an earlier version which had been used by the principal investigator in two previous studies.36,42 The component on ‘knowledge’ included a series of questions based on findings reported in the literature on the adverse health effects associated with ETS (e.g. ‘smoking by a pregnant woman during pregnancy can have harmful effects on the unborn child’; ‘smoke from a burning cigarette contains dangerous chemicals’). The ‘attitude’ component assessed personal feelings toward ETS (e.g. ‘I don’t like to breathe smoke from other people’s cigarettes’; ‘smoking should not be permitted at work’; ‘I have the right to ask other people not to smoke in my presence’). The segment on ‘preventive efforts’ presented questions on efforts undertaken by the women when exposed to tobacco smoke in their immediate environment (e.g. ‘I ask people not to smoke near me’; ‘I ask smokers to follow posted no-smoking regulations’; ‘when I am in a car or bus, I ask people around me not to smoke’). A five-point response scale (1 = strongly agree, 2 = agree, 3 = undecided, 4 = disagree, 5 = strongly disagree) was affixed to each question in the knowledge, attitudes and preventive efforts sections. Demographics were also elicited, including age, gender, ethnicity, income, education, employment, marital/partner status and number of children in the home, as well as the smoking status of the spouse/partner or any other adults living in the home. The instrument was pilot tested on a group of economically disadvantaged women who were not part of the present study, and feedback was elicited on the clarity of the questions and the time required to complete the instrument. The questionnaire was revised based on the feedback received. The instrument was administered by university extension personnel in the context of regularly scheduled group sessions. The purpose of the study was explained to the women, and they were invited to participate. The study design and instrumentation, including informed consent procedures, were approved by the appropriate university committee for research involving human subjects.
Exposure to ETS
Measures and analyses Composite measures were constructed for knowledge (10 items), attitudes (8 items) and preventive efforts (11 items) by grouping the individual questions in each category. In each case the composite measure was computed as the average response for the items in the group, thus yielding a range of possible scores of 1–5. In view of the positive wording of the individual questions, lower numerical scores on the composite measures correspond to greater knowledge of the health effects of exposure to ETS, attitudes reflecting greater concern about their exposure to ETS, and more assertive efforts taken to limit their exposure to ETS. Reliability coefficients (Cronbach’s alpha) for the knowledge, attitude and preventive efforts scales were 0.90, 0.78 and 0.92, respectively. Descriptive statistics and pairwise correlations were computed for all scale variables. Separate analyses of variance were performed taking, respectively, knowledge, attitudes and preventive efforts as outcome variables, and taking in each case education, employment, ethnicity, income and smoking status as explanatory variables. Subsequently, analysis of covariance was employed with preventive efforts as outcome, knowledge, attitudes and age as covariates, and education, ethnicity, employment status, income, smoking status, and home environment as additional explanatory variables. Home environment included separate variables indicating the presence or absence of children in the home, the presence or absence of other smokers in the home, and whether the woman was living with a spouse or partner. Education was measured as a grouped variable (1 = no high school degree, 2 = high school degree, 3 = some college, 4 = college degree), as was income (1 = less than $800 per month, 2 = $800–$999 per month, 3 = $1000–$1200 per month, 4 = more than $1200 per month). RESULTS
The average age of the respondents was 31.7 years, 51.4% were smokers and 48.6% were nonsmokers. Fifty-two per cent of the women were employed outside the home, 59.2% lived with a spouse or partner, and in 38.3% of cases there was a regular smoker in the home other than the respondent. Other demographic data as well as descriptive statistics for knowledge, attitudes and preventive efforts are presented in table 1. According to the analyses of variance, a general pattern emerged indicating that better knowledge, attitudes and preventive efforts were associated with being a nonsmoker, having a higher income and having more formal education. More precisely, knowledge scores were better for women who had a high school degree, some college or a college degree, compared to women with no high school degree (p
