Chest ACCP Education Calendar
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Guest Access | Sign In via User Name/Password
This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF) Free
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Article Archive
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via ISI Web of Science (6)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Iversen, L.
Right arrow Articles by Godden, D. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Iversen, L.
Right arrow Articles by Godden, D. J.
(Chest. 2005;128:2059-2067.)
© 2005 American College of Chest Physicians

Is Living in a Rural Area Good for Your Respiratory Health?*

Results From a Cross-sectional Study in Scotland

Lisa Iversen, MSc; Philip C. Hannaford, MD; David B. Price, FRCGP and David J. Godden, MD

* From the Department of General Practice & Primary Care (Mrs. Iversen, and Drs. Hannaford and Price) and Centre for Rural Health (Dr. Godden), University of Aberdeen, Aberdeen, UK.

Correspondence to: Lisa Iversen, MSc, Department of General Practice & Primary Care, University of Aberdeen, Foresterhill Health Centre, Westburn Rd, Aberdeen, AB25 2AY, UK; e-mail: l.iversen{at}abdn.ac.uk


   Abstract
TOP
 Abstract
Introduction
 Materials and Methods
 Results
 Discussion
 References
 
Study objectives: We aimed to investigate the epidemiology of self-reported chronic respiratory disease throughout Scotland, and to explore the relationship between quality of life and geographic location in those reporting disease.

Design: A cross-sectional study. Self-reported data on age, gender, socioeconomic factors, smoking habits, selected illnesses (major respiratory and atopic diseases, and other major conditions), respiratory symptoms, use of medicines and health services, and quality of life were collected using a postal questionnaire.

Participants: A total of 4,560 adults registered with 1 of 57 family practices (22 rural and 35 urban) throughout Scotland.

Results: The response rate was 60%. Following adjustment for potential confounders, participants from rural areas reported a significantly lower prevalence of any chest illness (adjusted odds ratio [OR], 0.72; 95% confidence interval [CI], 0.58 to 0.91), asthma (adjusted OR, 0.59; 95% CI, 0.46 to 0.76), and eczema/dermatitis (adjusted OR, 0.67; 95% CI, 0.52 to 0.87). Rural location was less likely than urban location to be associated with the reporting of persistent cough and phlegm and different symptoms (types of breathlessness and wheeze) indicative of asthma. No difference in prevalence was found for other respiratory problems. Participants from rural areas reporting COPD or emphysema, or cough or phlegm symptoms had significantly better quality of life scores than their urban counterparts.

Conclusions: In this study, living in a rural area was associated with a lower prevalence of asthma but not other chronic respiratory disorders, and a lower prevalence of some respiratory symptoms (including wheeze). Although the prevalence of COPD or emphysema did not differ between rural and urban areas, rural residency appeared to be associated with better health status among subjects with these conditions.

Key Words: asthma • COPD • quality of life • rural • Scotland • urban


   Introduction
TOP
 Abstract
 Introduction
Materials and Methods
 Results
 Discussion
 References
 
It has been suggested that people living in rural areas generally report better health, are less likely to be disabled or suffer from a long-term limiting illness, and are less likely to smoke than those living in urban areas.1 Rates of alcohol and drug dependence and psychiatric morbidity have been shown to be lower in rural rather than urban areas, although some of the difference may be due to socioeconomic differences.2 In contrast, patients living remote from cities have worse survival from lung or colorectal cancer than those living in cities (because of more advanced disease at diagnosis).3 In another study, standardized mortality ratios tended to be higher in the most rural areas than in other rural areas, perhaps indicating that any rural/urban gradient in mortality may not continue across the spectrum of locations.4

Several prevalence studies56 have considered geographic variations in asthma and respiratory symptoms. Few have specifically considered rural/urban variations of such conditions, perhaps because there is no agreed definition of rurality. Various approaches exist based on population density, population size, and social characteristics, or remoteness from urban centers and health-care facilities.7 Others advocate using a definition of rurality that is most sensible for the issue being examined.8

In the United Kingdom, exercise-induced bronchospasm among Highland schoolchildren was found to be significantly higher in one of the most rural areas studied (Skye) compared with the rest of the United Kingdom or other areas in the Highlands.9 Others have found that wheeze in the past year, both with and without a diagnosis of asthma, and before adjustment for other factors, was lower in rural compared with urban areas.10

Chronic respiratory disease (asthma, chronic bronchitis, COPD, and emphysema) imposes significant health burdens and quality of life impairments.11121314 Scottish data show that respiratory disease is the third most common diagnosis of inpatient and day-case discharges1 and accounts for 8% of primary care prescribing.15 Compared with urban areas, it is more expensive to deliver health-care services in rural parts of Scotland.16 This may be because the cost of providing the same standard of care is higher, or because patterns of disease vary significantly between different locations. Furthermore, it is unknown whether the quality of life of individuals with chronic respiratory disease living in rural and urban areas is different. In addition to affecting the distribution of health services, differences in the prevalence of symptoms between rural and urban locations may provide clues toward mechanisms of disease and may give an indication of unmet need. Our cross-sectional study, although unable to consider cause and effect, was a suitable starting point for the future investigation of potential influences on the presentation of respiratory illness. Given the importance of chronic respiratory disease, we investigated the epidemiology of self-reported chronic respiratory disease across Scotland, and explored the relationship between quality of life and geographic location in those reporting such problems.


   Materials and Methods
TOP
 Abstract
 Introduction
 Materials and Methods
Results
 Discussion
 References
 
Data Collection
Ethical approval for the study was granted by the Multi-Centre Research Ethics Committee for Scotland and by the Local Research Ethics Committees of the 57 volunteer general practices (22 rural and 35 urban) throughout Scotland that participated in the study.

When we began the study, there was no agreed simple definition of rurality in Scotland that could be used for epidemiologic research. We defined, therefore, rurality in terms of family practice (general practice). Using the National Health Service in Scotland, Information and Statistics Division classification at that time, rural practices were those that received rural practice payments for one third or more of their registered patients.17 These payments are made by the government to compensate practitioners for the scattered nature of their registered patients, principally for the increased time and expense spent visiting patients a minimum of 4.8 km from the practice center, and for the limited number of patients on their lists. Adjustments are made to the payments if a practice covers an area where there are concentrations of patients, eg, in a village. Practices were invited to participate in the study through existing primary care research networks and by a letter sent to a random selection of general practices on the Scottish mainland.

Each practice identified a random sample of 80 registered adults, stratified by age (16 to 50 years, >50 years) and sex. Each person was allocated a unique identification number by the practices so that confidentiality could be preserved. Questionnaire packs were mailed to the individuals by the practices on our behalf, between October 2001 and October 2002. The practices sent an identical reminder pack to nonrespondents 3 to 6 weeks after the initial mailing. Following the mailing of reminders, practices were asked to provide aggregated details of the age and sex of nonrespondents.

The questionnaire pack included a letter from the general practice, a letter from the research team, a patient information sheet, a questionnaire, and a consent form. The questionnaire pack was piloted on 100 patients from two practices, and minor amendments were made. The final questionnaire collected self-reported data on age; gender; socioeconomic factors; smoking habits; selected illnesses (major respiratory and atopic diseases, and other major chronic conditions including heart disease, diabetes and depression), based on items included in another respiratory study18; respiratory symptoms (cough, phlegm, wheeze, breathlessness), based on questions modified from the Medical Research Council (MRC) 1986 Respiratory Symptoms Questionnaire19; use of medicines and health services; the generic health status measure (the Short Form-36 [SF-36])20; and the respiratory-specific quality of life measure (the Airways Questionnaire 20 [AQ20]).2122

The SF-36, which was completed by all respondents, contains 36 items that measure eight health domains: physical functioning, social functioning, role limitations due to physical problems, role limitations due to emotional problems, mental health, energy and fatigue, pain, and general perception of health. Generic measures of health status are designed to incorporate a range of aspects of health status.23 The AQ20 measures quality of life in both asthma and COPD patients,2224 and was particularly attractive for use in a postal questionnaire due to its low respondent burden, requiring < 3 min to complete the 20 items.22

Data Analysis
Data were entered into Microsoft Access (Microsoft; Redmond, WA), and data analysis was completed using statistical software (SPSS for Windows, version 9.01; SPSS; Chicago, IL). The analysis explored the relationship between the location of the participants’ general practice (rural or urban), used as a proxy measure of whether respondents lived in rural or urban areas, and different health outcomes. Differences in the characteristics of respondents from rural and urban practices were assessed using the {chi}2 test. Univariate associations between the prevalence of self-reported illness and symptoms, and rural/urban practice location were examined by binary logistic regression. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were then calculated allowing for gender, age group (generally 16 to 24 years, 25 to 34 years, 35 to 44 years, 45 to 54 years, 55 to 64 years, 65 to 74 years, and > 75 years, but collapsed for some analyses); smoking (current, former, never smoked > 100 cigarettes); Carstairs Morris deprivation category (Depcat) based on postal code (Depcat 1–2, Depcat 3–4, Depcat 5–7; higher values indicating less affluence)25; and employment (employed, not employed, retired, student, or unable to work due to illness). In the United Kingdom, the term chronic bronchitis is often used to describe COPD,26 so we grouped together respondents who reported having chronic bronchitis, COPD, or emphysema. We suspected that some of the respondents who reported chronic bronchitis might be misreporting acute bronchitis; therefore, we looked at the overlap among the three conditions and the age distribution of the respondents.

In order to examine whether there were differences in the severity of respiratory disease between rural and urban practice groups, we investigated the medicines used by respondents who reported having asthma. These respondents were categorized into one of three treatment groups based on British Thoracic Society guidelines27: those using inhaled short-acting ß2-agonists only; those using inhaled short-acting ß2-agonists and a regular inhaled steroid; and those using short-acting ß2-agonists and other add-on therapies. The association between treatments used and location was assessed using the {chi}2 test.

The eight SF-36 domain scores for each respondent could range between 0 (worst) and 100 (best health state). Since the scores were not normally distributed, median scores (and the interquartile range [IQR]) were calculated for each domain. Mann-Whitney U tests compared the SF-36 scores of respondents with each respiratory condition or symptom living in rural or urban practice locations. Since multiple testing may find a statistically significant result by chance,28 we used the more stringent value of 1% (p < 0.01) for statistical significance.

Responses to the AQ20 questions were summed to give a total score between 0 (least) and 20 (most impaired health state). Median AQ20 scores and IQRs were calculated for respondents reporting asthma, chronic bronchitis, COPD/emphysema, and selected symptoms of these conditions. The scores of respondents living in rural and urban practice locations were compared using the Mann-Whitney U test.


   Results
TOP
 Abstract
 Introduction
 Materials and Methods
 Results
Discussion
 References
 
Of the 4,560 questionnaires mailed, 142 were returned not delivered, 28 individuals had left the practice, 7 had died, 2 were overseas; and 5 questionnaires were completed by children. The corrected response rate was 60% (2,603 of 4,376 questionnaires). More individuals registered with a rural practice responded than those with an urban practice: 65% vs 56% (p < 0.001). Respondents were more likely to be women (55% vs 45%, p < 0.001) and older than nonrespondents; mean age was 52 years vs 47 years, respectively (p < 0.001).

Table 1 shows the characteristics of respondents by location. Most respondents were white (2,573 of 2,582 respondents). There were no differences between rural and urban respondents in terms of gender, age, education, or smoking status. Respondents from rural practices were more likely to be retired or otherwise not employed, and less likely to be not working because of illness or disability than urban respondents (p < 0.001). Respondents from rural practices were more likely to be in the middle Depcat (3–4) and less likely to be in the most deprived group (Depcat 5–7) than those from urban practices (p < 0.001).


View this table:
[in this window]
[in a new window]

  		Table 1. Characteristics of Respondents by Location

 
The unadjusted OR for any self-reported chest illness, asthma, eczema/dermatitis, and rheumatic troubles/arthritis was significantly lower among participants from rural areas than for those from urban areas (Table 2 ). After adjustment, only the ORs for any self-reported chest illness, asthma, and eczema/dermatitis remained statistically significant. We found a large overlap between respondents reporting COPD or emphysema but did not find an overlap in the reporting of chronic bronchitis and COPD or emphysema. A small proportion of the respondents who reported chronic bronchitis, COPD, or emphysema were < 45 years old (13.5%; 34 of 251 respondents). Most of this younger group reported having chronic bronchitis, with only one respondent indicating COPD and none reporting emphysema.


View this table:
[in this window]
[in a new window]

  		Table 2. Prevalence of Self-Reported Conditions by Location and Their Association With Location

 
More respondents reported symptoms than specific diagnoses. The prevalence of respiratory symptoms was generally lower among participants from rural practices than urban practices. Fewer respondents from rural areas reported breathlessness than those from urban areas, and if this symptom occurred were more likely to report mild symptoms (Table 3 ). After adjustment, respondents from rural locations were significantly less likely than those from urban locations to report persistent cough and phlegm, being disabled from walking due to breathlessness because of a reason other than lung disease, and various types of wheeze. In particular, respondents from rural practices were less likely to report symptoms suggestive of asthma (attacks of wheeze or whistling in the chest during the previous 12 months, and attacks of shortness of breath with wheeze).


View this table:
[in this window]
[in a new window]

  		Table 3. Prevalence of Self-Reported Respiratory Symptoms and Where Appropriate, Proportion of Those With Different Severity by Location and Their Association With Location

 
Among respondents reporting asthma, we found no differences between location and types of medications used: inhaled short-acting ß2-agonists only (20.6% rural vs 22.0% urban); those using inhaled short-acting ß2-agonists and a regular inhaled steroid (42.3% rural vs 42.2% urban); and those using short-acting ß2-agonists and other add-on therapies (37.1% rural vs 35.8% urban) [p = 0.764].

The median SF-36 scores for the respondents reporting different respiratory conditions and selected symptoms are shown in Table 4 . The respondents who did not have any of the respiratory or other chronic conditions had the highest SF-36 scores. For each of the conditions and symptoms, we found impairments to most aspects of health status with the exception of the median SF-36 score for role limitations due to emotional problems. Respondents reporting asthma had particularly low SF-36 scores in energy and fatigue, and general health perception domains. Those reporting COPD/emphysema had the lowest SF-36 scores of all conditions assessed, with low median scores in all of the domains especially for physical functioning, role limitations due to physical problems, and due to emotional problems.


View this table:
[in this window]
[in a new window]

  		Table 4. Median (IQR) SF-36 Scores for Respondents Reporting Different Respiratory Conditions and Symptoms

 
Respondents who reported persistent cough and phlegm had similar scores to those reporting wheeze symptoms. Their scores were low in the energy and fatigue, pain, and general health perception aspects of health status.

When there were significant differences between the SF-36 scores of the two groups, the SF-36 scores of respondents living in rural areas were higher (ie, indicating better health status) than those of their urban counterparts (data not shown). There were no differences for respondents with reported asthma. Rural participants reporting chronic bronchitis had better pain scores than those from urban practices (p < 0.001). The median scores for role limitations from physical problems (p = 0.009), mental health (p = 0.001), and energy and fatigue (p = 0.001) of rural respondents reporting COPD/emphysema were higher (signifying better health status) than those for urban participants with this condition.

There were more rural/urban differences found for symptoms, particularly for cough and phlegm, where the domain scores for energy and fatigue, pain, and general health perception were significantly higher among respondents from rural practices than from those from urban practices. Of all the conditions and symptoms assessed, a significant rural/urban difference in the perception of general health domain was only found for cough and for phlegm.

Most respondents who reported a respiratory condition or symptom completed the respiratory-specific quality of life questionnaire (Table 5 ). The distribution of the total AQ20 scores for individuals with asthma was skewed toward the milder end of quality of life impairment when compared with the scores of respondents with COPD/emphysema (data not shown). Median AQ20 scores were generally lower representing better quality of life among respondents from rural practices than from urban practices. AQ20 scores were significantly lower for respondents from rural practices for COPD/emphysema and for persistent cough and phlegm, when compared to those from urban practices.


View this table:
[in this window]
[in a new window]

  		Table 5. Median (IQR) AQ20 Scores of Respondents Reporting Different Respiratory Conditions and Symptoms

 

   Discussion
TOP
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
References
 
Compared with respondents from urban practices, rural participants reported a significantly lower prevalence of asthma and eczema/dermatitis; a lower prevalence of respiratory symptoms (including wheeze); and, among those with COPD/emphysema or symptoms of chronic cough or phlegm, better scores in certain aspects of quality of life. This was a large study with a good geographic spread. In the United Kingdom, > 95% of the population are registered with a general practitioner.29 Recruitment through general practices and their registers ensured as much as possible that the study population was representative of the general population. We looked at a number of respiratory conditions and symptoms affecting both young and older adults, allowing us to compare a number of aspects of health, including quality of life. The prevalence of respiratory disease reported by respondents from different locations could have been affected by differences in the participating general practices (eg, in the level of investigation undertaken or diagnostic terms used), as well as by differences in the recall of diagnoses. It is noteworthy, however, that differences also existed between participants from different locations in the reporting of symptoms, which are unlikely to have been affected by such problems. There were no differences between rural and urban respondents in patterns of asthma-related treatment. Further research is needed into whether there are important geographic variations in the presentation of respiratory symptoms to general practices, and in their subsequent management.

Response bias may have occurred if recipients of the questionnaire chose to participate in the study depending on the presence of chronic respiratory disease. Selection bias may have arisen from the 60% response rate and from the different response rates from rural and urban participants. Respondents were more likely to be women and were older than nonrespondents. Although respondents from rural practices were more likely to be retired than respondents from urban practices, they were not older. We do not know why the respondents had retired, and so it is difficult to know how these differences may have affected our findings. If rural respondents had retired because of poor respiratory health, it is unlikely to explain the rural/urban differences observed. Alternatively, if respondents from rural practices had retired early due to ill health from conditions other than respiratory disease, and these conditions were mutually exclusive from respiratory disease, this may account for some of the results. However, we found no significant excess of other diseases among rural respondents.

Other research about respiratory symptoms and illness found that nonrespondents were more likely to be current smokers, manual workers, and have a higher prevalence of asthma and a number of respiratory symptoms than respondents to a postal questionnaire.30 If similar problems affected our results, we will have underestimated the prevalence of respiratory problems. The small number of respondents reporting some respiratory conditions limited the statistical power of our study to examine further rural/urban relationships for these problems. We may, therefore, have missed differences that exist between areas. In addition, we were restricted in our ability to explore in detail geographic differences in quality of life scores of respondents reporting COPD or emphysema.

Our results relied on self-reported information and could have been affected by information bias. An Australian study31 among middle-aged and older adults found little difference between the self-reported prevalence of ever asthma, chronic bronchitis and emphysema, and the prevalence of these conditions confirmed by a doctor. A cross-sectional study investigating the relationship between pulmonary test variables and self-reported asthma and wheeze concluded that questions about the self-report of asthma and wheezing had high criterion validity when compared with concurrently measured pulmonary function variables.32

The Detection, Intervention, and Monitoring of COPD and Asthma study33 of 1,155 subjects recruited from 10 general practices in the Netherlands found that 50% of the general population from 25 to 70 years old had respiratory symptoms or objective indicators of obstructive airways disease. A postal survey (based on the MRC questionnaire) of obstructive lung disease among 6,610 adults aged 35 to 36, 50 to 51, and 65 to 66 years in northern Sweden found no difference in the occurrence of self-reported asthma or respiratory symptoms between rural and urban areas.34 Our results broadly concur with the findings of the European Community Respiratory Health Survey, in which the prevalence rates of respiratory symptoms were found to be particularly high among the UK centers.5 We found a higher prevalence of asthma among adults than previously reported in large-scale Scottish surveys but a similar prevalence of wheeze.35 Differences may partly be due to differences in study methodology. We adjusted our results for group differences in socioeconomic circumstances as well as other possible confounders including age, gender, and smoking. It is possible, however, that residual confounding may account, at least in part, for the remaining differences.

The cross-sectional nature of our study prevents us from distinguishing between cause and effect in any relationships found. Nevertheless, it is important to consider why there might be rural/urban differences in the prevalence of self-reported asthma and asthma-related symptoms (if real). There may be differences between rural and urban areas that were not measured, such as atmospheric pollution, body mass index (BMI), diet, exposure to farming and occupational exposures, which may account for the observations. For instance we did not collect information to allow us to calculate BMI, which has been shown to be important for chronic respiratory disease.3637 Rural/urban differences in the prevalence of asthma could have occurred if urban respondents with a high BMI were more likely to be diagnosed as having asthma than rural respondents who had a high BMI. This seems unlikely, but further research is required to examine this.

In our study, rurality was defined on the basis of current residency. We do not know if the participants were of rural origin. In France, the prevalence of asthma and adult allergy was found to be significantly lower in those who had ever lived in the country, particularly in subjects who began living in the country before 17 years of age.38 Evidence from a study of Swedish conscripts suggests that the protective effect of farming environments during childhood on adult asthma is a recent phenomenon observed only among conscripts born after 1970.39 In Austria, children living on a farm were found to have less asthma, hay fever, and allergic sensitization than children from a nonfarming environment.40 Children who did not live on a farm but who had regular contact with farm animals had a lower prevalence of allergic sensitization, suggesting that contact with livestock might have a protective role against allergy, perhaps through greater exposure to infections. There is some evidence that if the immune system is exposed to high levels of allergen, as might be the case in rural settings, a form of immune tolerance may occur, perhaps resulting in less allergic disease.41

Respondents with chronic respiratory disease reported impaired quality of life on both generic and disease-specific measures. The apparently better quality of life of respondents with COPD or emphysema living in rural areas might be explained by confounding by socioeconomic or other factors such as perhaps differences in severity. Unfortunately we had too little data to enable us to adjust our results for these variables. This merits investigation in a larger study.

Our results indicate that living in a rural area is associated with a lower prevalence of asthma but not other chronic respiratory disease, and a lower prevalence of some respiratory symptoms. Although the prevalence of COPD or emphysema may not differ between rural and urban areas, rural residency may be associated with better health status among subjects with these conditions.


   Acknowledgements
 
We thank the general practices and their patients for taking part in the study and Mrs. Clark for data entry and mailing assistance.


   Footnotes
 
Abbreviations: AQ20 = Airways Questionnaire 20; BMI = body mass index; CI = confidence interval; Depcat = deprivation category; IQR = interquartile range; MRC = Medical Research Council; OR = odds ratio; SF-36 = Short Form-36

Funding for this study was provided by the Chief Scientist Office of the Scottish Executive.

At the time of the study, Lisa Iversen held a Research Training Fellowship of the Chief Scientist Office of the Scottish Executive.

Received for publication February 2, 2005. Accepted for publication April 21, 2005.


   References
TOP
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 References
 

  1. Social focus on urban rural Scotland 2003. Edinburgh, Scotland: Scottish Executive, 2003
  2. Paykel, ES, Abbott, R, Jenkins, R, et al Urban-rural mental health differences in Great Britain: findings from the National Morbidity Survey. Psychol Med 2000;30,269-280[CrossRef][ISI][Medline]
  3. Campbell, NC, Elliott, AM, Sharp, L, et al Rural and urban differences in stage at diagnosis of colorectal and lung cancers. Br J Cancer 2001;87,910-914
  4. Bentham, CG Mortality rates in the more rural areas of England and Wales. Area 1984;16,219-226
  5. European Community Respiratory Health Survey.. Variations in the prevalence of respiratory symptoms, self-reported asthma attacks, and use of asthma medication in the European Community Respiratory Health Survey (ECRHS). Eur Respir J 1996;9,687-695[Abstract]
  6. Austin, JB, Kaur, B, Anderson, HR, et al Hay fever, eczema, and wheeze: a nationwide UK study (ISACC, international study of asthma and allergies in childhood). Arch Dis Child 1999;81,225-230[Abstract/Free Full Text]
  7. Rousseau, N What is rurality? Cox, J eds. Rural general practice in the United Kingdom [occasional paper 71] 1995 Royal College of General Practitioners. London, UK:
  8. Hoggart, K Let’s do away with rural. J Rural Studies 1990;6,245-257
  9. Austin, JB, Russell, G, Adam, MG, et al Prevalence of asthma and wheeze in the Highlands of Scotland. Arch Dis Child 1994;71,211-216[Abstract]
  10. Court, CS, Cook, DG, Strachan, DP Comparative epidemiology of atopic and non-atopic wheeze and diagnosed asthma in a national sample of English adults. Thorax 2002;57,951-957[Abstract/Free Full Text]
  11. Chung, F, Barnes, N, Allen, M, et al Assessing the burden of respiratory disease in the UK. Respir Med 2002;96,963-975[CrossRef][ISI][Medline]
  12. Soriano, JB, Maier, WC, Egger, P, et al Recent trends in physician diagnosed COPD in women and men in the UK. Thorax 2000;55,789-794[Abstract/Free Full Text]
  13. Osman, LM, Godden, DJ, Friend, JAR, et al Quality of life and hospital re-admission in patients with chronic obstructive pulmonary disease. Thorax 1997;52,67-71[Abstract/Free Full Text]
  14. Juniper, EF, Guyatt, GH, Ferrie, PJ, et al Measuring quality of life in asthma. Am Rev Respir Dis 1993;147,832-838[ISI][Medline]
  15. Scottish Health Statistics. Prescribing dispensing information from ISD. Available at: www.show.scot.nhs.uk/isd/primary_care/pservices/pcare_pservices.htm. Accessed June 20, 2005
  16. Scottish Executive Health Department.. Fair shares for all: report of the National Review of Resource Allocation for the NHS in Scotland. 1999 Scottish Executive. Edinburgh, Scotland:
  17. Statement of fees and allowances payable to general medical practitioners in Scotland from 1 April 1990: The red book. Available at: www.show.scot.nhs.uk/sfa/; accessed June 20, 2005
  18. Edwards, CA, Osman, LM, Godden, DJ, et al Relationship between birth weight and adult lung function: controlling for maternal factors. Thorax 2003;58,1061-1065[Abstract/Free Full Text]
  19. Medical Research Council’s Committee on Environmental and Occupational Health.. Questionnaire on respiratory symptoms. 1986 Medical Research Council. London, UK:
  20. Garratt, AM, Ruta, DA, Abdalla, MI, et al The SF-36 health survey questionnaire: an outcome measure suitable for routine use within the NHS? BMJ 1993;306,1440-1444[ISI][Medline]
  21. Quirk, FH, Jones, PW Repeatability of two new short airways questionnaires. Thorax 1994;49,1075p
  22. Barley, EA, Quirk, FH, Jones, PW Asthma health status measurement in clinical practice: validity of a new short and simple instrument. Respir Med 1998;92,1207-1214[CrossRef][ISI][Medline]
  23. Fitzpatrick, R, Davey, C, Buxton, MJ, et al Evaluating patient-based outcome measures for use in clinical trials. Health Technol Assessment 1998;2,10-11
  24. Hajiro, T, Nishimura, K, Jones, PW A novel, short, and simple questionnaire to measure health-related quality of life in patients with chronic obstructive pulmonary disease. Am J Respir Crit Care Med 1999;159,1874-1878[Abstract/Free Full Text]
  25. Carstairs, V, Morris, R Deprivation and health in Scotland. 1991 Aberdeen University Press. Aberdeen, UK:
  26. National Institute for Clinical Excellence. Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care. Available at: www.nice.org.uk/CG012NICEguideline; January 1, 2005
  27. British Thoracic Society.. British guideline on the management of asthma. Thorax 2003;58(suppl 1),117-128
  28. Altman, DG Practical statistics for medical research. 1991,211 Chapman & Hall. London, UK:
  29. Bowling, A Lists of patients. Bowling A. Research methods in health 1997,156 Open University Press. Buckingham, UK:
  30. Ronmark, E, Lundqvist, A, Lundback, B, et al Non-responders to a postal questionnaire on respiratory symptoms and diseases. Eur J Epidemiol 1999;15,293-299[CrossRef][ISI][Medline]
  31. Abramson, M, Matheson, M, Wharton, C, et al Prevalence of respiratory symptoms related to chronic obstructive pulmonary disease and asthma among middle aged and older adults. Respirology 2002;7,325-331[CrossRef][ISI][Medline]
  32. Senthilselvan, A, Dosman, J, Chen, Y Relationship between pulmonary test variables and asthma and wheezing: a validation of self-report of asthma. J Asthma 1993;30,185-193[CrossRef][ISI][Medline]
  33. van den Boom, G, van Shayck, CP, Rutten-van Mölken, M, et al Active detection of chronic obstructive pulmonary disease and asthma in the general population: results and economic consequences of the DIMCA Program. Am J Respir Crit Care Med 1998;158,1730-1738[Abstract/Free Full Text]
  34. Lundbäck, B, Nyström, L, Rosenhall, L, et al Obstructive lung disease in northern Sweden: respiratory symptoms assessed in a postal survey. Eur Respir J 1991;4,257-266[Abstract]
  35. Primatesta, P, McMunn, A, Brookes, M Respiratory symptoms and asthma. Shaw, A McMunn, A Field, J eds. The Scottish Health Survey 1998 2000;Volume 1,67-91 The Stationary Office. Edinburgh, Scotland:
  36. Guerra, S, Sherrill, DL, Bobadilla, A, et al The relation of body mass index to asthma, chronic bronchitis, and emphysema. Chest 2002;122,1256-1263[Abstract/Free Full Text]
  37. Luder, E, Ehrlich, RI, Lou, WYW, et al Body mass index and the risk of asthma in adults. Respir Med 2004;98,29-37[CrossRef][ISI][Medline]
  38. Kauffmann, F, Oryszczyn, MP, Maccario, J The protective role of country living on skin prick tests, immunoglobulin E and asthma in adults from the Epidemiological Study on the Genetics and Environment of Asthma, Bronchial Hyperresponsiveness and Atopy. Clin Exp Allergy 2002;32,379-386[CrossRef][ISI][Medline]
  39. Bråbäck, L, Hjern, A, Rasmussen, F Trends in asthma, allergic rhinitis and eczema among Swedish conscripts from farming and non-farming environments: a nationwide study over three decades. Clin Exp Allergy 2004;34,38-43[CrossRef][ISI][Medline]
  40. Riedler, J, Eder, W, Oberfeld, G, et al Austrian children living on a farm have less hay fever, asthma and allergic sensitisation. Clin Exp Allergy 2000;30,194-200[CrossRef][ISI][Medline]
  41. Platts-Mills, TA, Vaughan, JW, Blumenthal, K, et al Serum IgG and IgG4 antibodies to Fel d 1 among children exposed to 20 microg Fel d 1 at home: relevance of a nonallergic modified Th2 response. Int Arch Allergy Immunol 2001;124,126-129[CrossRef][ISI][Medline]




This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF) Free
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Article Archive
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via ISI Web of Science (6)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Iversen, L.
Right arrow Articles by Godden, D. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Iversen, L.
Right arrow Articles by Godden, D. J.

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS