Search

This paper investigates associations between hazardous jobs, mental health and wellbeing among Thai adults. In 2005, 87 134 distance-learning students from Sukhothai Thammathirat Open University completed a self-administered questionnaire; at the 2009 follow-up 60 569 again participated. Job characteristics were reported in 2005, psychological distress and life satisfaction were reported in both 2005 and 2009. We derived two composite variables grading psychologically and physically hazardous jobs and reported adjusted odds ratios (AOR) from multivariate logistic regressions. Analyses focused on cohort members in paid work: the total was 62 332 at 2005 baseline and 41 671 at 2009 follow-up. Cross-sectional AORs linking psychologically hazardous jobs to psychological distress ranged from 1.52 (one hazard) to 4.48 (four hazards) for males and a corresponding 1.34–3.76 for females. Similarly AORs for physically hazardous jobs were 1.75 (one hazard) to 2.76 (four or more hazards) for males and 1.70–3.19 for females. A similar magnitude of associations was found between psychologically adverse jobs and low life satisfaction (AORs of 1.34–4.34 among males and 1.18–3.63 among females). Longitudinal analyses confirm these cross-sectional relationships. Thus, significant dose–response associations were found linking hazardous job exposures in 2005 to mental health and wellbeing in 2009. The health impacts of psychologically and physically hazardous jobs in developed, Western countries are equally evident in transitioning Southeast Asian countries such as Thailand. Regulation and monitoring of work conditions will become increasingly important to the health and wellbeing of the Thai workforce.

Background and aims Waist circumference (WC), waist-to-hip ratio (WHR) and waist-to-stature ratio (WSR), being common proxy measures of abdominal obesity, are useful tools in epidemiologic studies, but little is known about their validity when the indices are derived from self-reported measurements. We determine and compare the validity of self-reported WC, WHR and WSR in order to identify the optimal index for use in epidemiologic surveys. Methods and Results Technician- and self-reported measurements of height, waist and hip circumference were obtained from 613 Thai adults (mean age 35 years). Regarding technician-reported measurements as reference, diagnostic test properties were derived and performances of the indices compared using receiver-operator-characteristic curves and the area-under-the-curve (AUC) analyses. There was good agreement between technician- and self-reported measurements for WC and WSR (concordance correlation coefficients ranged from 0.84 to 0.90) but not for WHR (0.50 in men, 0.45 in women). The sensitivity and specificity of self-reported WC and self-reported WSR as measures of abdominal obesity were superior to those of self-reported WHR in both sexes. AUCs for WC and WSR were comparable (0.93 and 0.92, respectively, in men; 0.88 and 0.87 in women) and significantly higher than for WHR (0.80 in men; 0.76 in women; p Conclusion WC and WSR derived from self-reported waist and height measurements are valid methods for determining abdominal obesity. Self-reported measurements should not be used to derive the WHR. In Asian populations, WSR may be the optimal index of abdominal obesity when measurements are derived from self-reports in epidemiologic surveys.

We report associations between social capital and health among 82,482 adults in a national cohort of Open University students residing throughout Thailand.After adjusting for covariates, poor self-assessed health was positively associated with low social trust (OR = 1.88; 95% CI 1.76—2.01) and low social support (OR = 1.79; 95% CI 1.63—1.95). In addition, poor psychological health was also associated with low social trust (OR = 2.52; 95% CI 2.41—2.64) and low social support (OR = 1.80; 95% CI 1.69—1.92). Females, elderly, unpartnered, low income, and urban residents were associated with poor health. Findings suggest ways to improve social capital and heath in Thailand and other middle-income countries.

This study analyses urban and rural health service use before and after the introduction of the Universal Coverage Scheme (UCS). Using data from the Thai national health surveys of 2001 and 2005, the study utilises age–sex adjusted concentration indices to measure within-area differences in use of health services among populations distinguished by socioeconomic status. Between 2001 and 2005, the UCS substantially reduced Thailand’s uninsured population (from 42.5% to 7.0% in urban areas and from 24.9% to 2.7% in rural areas). The implementation of the UCS changed patterns of health services use, particularly for rural people and the urban poor, by placing greater emphasis on primary healthcare. Relevant policy recommendations should focus on continued improvement of primary health services, and ensuring adequate and timely referrals to secondary and tertiary health services when the need arises.

Thailand implemented a Universal Coverage Scheme (UCS) of national health insurance in April 2001 to finance equitable access to health care. This paper compares inequalities in health service use before and after the UCS, and analyses the trend and determinants of inequality. The national Health and Welfare Surveys of 2001 and 2005 are used for this study. The concentration index for use of ambulatory care among the population reporting a recent illness is used as a measure of health inequality, decomposed into contributing demographic, socio-economic, geographic and health insurance determinants. As a result of the UCS, the uninsured group fell from 24% in 2001 to 3% in 2005 and health service patterns changed. Use of public primary health care facilities such as health centres became more concentrated among the poor, while use of provincial/general hospitals became more concentrated among the better-off. Decomposition analysis shows that the increasingly common use of health centres among the poor in 2005 was substantially associated with those with lower income, residence in the rural northeast and the introduction of the UCS. The increasing use of provincial/general hospitals and private clinics among the better-off in 2005 was substantially associated with the government and private employee insurance schemes. Although the UCS scheme has achieved its objective in increasing insurance coverage and utilization of primary health services, our findings point to the need for future policies to focus on the quality of this primary care and equitable referrals to secondary and tertiary health facilities when required.

The aim of this study was to estimate the prevalence of smoking among students in an open university in Thailand and to describe smoking patterns in relation to the personal and social characteristics of the sample. A self-administered questionnaire survey was conducted in 2005 with 87 134 open-university students in Thailand; the respondents aged 15 to 60 years (N = 84 315) are the participants in this study. We found a substantial difference in smoking prevalence by sex, with a much higher proportion of smoking male (20.9%) than female (1.0%) students in all sociodemographic categories. Smoking decreased among men with a higher level of education or income; in contrast, among women, higher incomes were associated with more smoking. Most of the smokers started smoking in high school. The findings provide evidence that future policy making should aim to reduce smoking among the younger population in Thailand, and in particular, they point to the need to preserve low smoking rates among women.

Background: As obesity increases, middle-income countries are undergoing a health-risk transition. We examine the association between socioeconomic status (SES) and emerging obesity in Thailand, and ascertain if an inverse relationship between SES and obesity has appeared. Methods: The data derived from 87 134 individuals (54% female; median age, 29 years) in a national cohort of distance-learning Open University students aged 15-87 years and living throughout Thailand. We calculated adjusted odds ratios for associations of SES with obesity (body mass index, ≥25) across 3 age groups by sex, after controlling for marital status, age, and urbanization. Results: Obesity increased with age and was more prevalent among males than females (22.7% vs 9.9%); more females were underweight (21.8% vs 6.2%). Annual income was 2000 to 3000 US dollars for most participants. High SES, defined by education, income, household assets, and housing type, associated strongly with obesity-positively for males and inversely for females-especially for participants younger than 40 years. The OR for obesity associated with income was as high as 1.54 for males and as low as 0.68 for females (P for trend

Purpose In middle-income countries, interest in the study of inequalities in health has focused on aggregate types of health outcomes, like rates of mortality. This work moves beyond such measures to focus on disease-specific health outcomes with the use of national health survey data. Methods Cross-sectional data from the national Health and Welfare Survey 2003, covering 52,030 adult aged 15 or older, were analyzed. The health outcomes were the 20 most commonly reported diseases. The age-sex adjusted concentration index (C∗) of ill health was used as a measure of socioeconomic health inequality (values ranging from −1 to +1). A negative (or positive) concentration index shows that a disease was more concentrated among the less well off (or better off). Crude concentration indices (C) for four of the most common diseases were also decomposed to quantify determinants of inequalities. Results Several diseases, such as malaria (C∗ = −0.462), goiter (C∗ = −0.352), kidney stone (C∗ = −0.261), and tuberculosis (C∗ = −0.233), were strongly concentrated among those with lower incomes, whereas allergic conditions (C∗ = 0.174) and migraine (C∗ = 0.085) were disproportionately reported by the better off. Inequalities were found to be associated with older age, low education, and residence in the rural Northeast and rural North of Thailand. Conclusions Pro-equity health policy in Thailand and other middle-income countries with health surveys can now be informed by national data combining epidemiological, socioeconomic and health statistics in ways not previously possible.

Breast cancer incidence may be increasing in Thailand but very little research has assessed core breast cancer risk factors in this country. We used baseline questionnaire data from a national cohort study of Thai Open University students in an exploratory case-control study of breast cancer. The study included 43 female cases and 860 age-matched controls selected from the remaining 47,271 female cohort participants. Odds ratios and 95% confidence intervals were calculated using conditional logistic regression. The women were predominantly premenopausal. Taller women had an increased risk of breast cancer (OR = 2.3, 95% CI 1.1–4.8, for height ≥160 cm vs ≤154 cm) as did women with non-insulin dependent diabetes mellitus (OR = 8.4, 95% CI 1.7–41). Women with older siblings had a reduced risk of breast cancer compared to those firstborn (OR = 0.3, 95% CI0.2–0.7). Although limited by small case numbers, our findings suggest substantial increases in breast cancer rates in Thailand could be expected in the future.

Job strain (high demands and low control) is a widely used measure of work stress. The authors introduce a new way of looking at work stress by combining job strain with job insecurity, a combination increasingly prevalent in contemporary economies, using data from a cross-sectional survey (N = 1,188) of mid-aged Australian managers and professionals. Those reporting both strain and insecurity showed markedly higher odds for mental and physical health problems (depression: odds ratio [OR] 13.88, 95% confidence interval [CI] 5.67-34.01; anxiety: OR 12.88, CI 5.12-32.39; physical health problems: OR 3.97, CI 1.72-9.16; and poor self-rated health: OR 7.12, CI 2.81-18.01). Job strain and insecurity showed synergistic associations with health, and employees experiencing both could be at heightened health risk.

There is increasing evidence for a role for bedding items in the development of asthma. The use of some forms of synthetic bedding, such as foam mattresses and pillows, is associated with a significantly increased risk of childhood wheeze. Our aim was to examine prospectively whether the use of synthetic cocoon/baby nests in infancy is associated with the subsequent development of wheeze in childhood. Data collected in 1988 as part of the Tasmanian Infant Health Survey were linked to the cross-sectional Childhood Asthma Survey conducted in 1995 in Tasmania, Australia. We were able to match 863 records out of the 1111 in the 1988 survey. Information including parental, child-care, and the infant's sleeping environment was collected at home interview in 1988 when the infant was 1 month of age. Data including sleep environment and asthma symptoms were available for each child at age 7 years. A generalised linear model was used to calculate the adjusted relative risk (RR) estimates for symptoms of wheeze and infant cocoon use. For children who were placed in a cocoon in infancy, there was an increased risk of recent wheeze (adjusted RR = 4.33 [95% CI 2.08, 9.02]) and night wheeze (adjusted RR = 3.35 [95% CI 1.52, 7.39]) at age 7 years. In view of the increasing prevalence of childhood asthma, the identification of potentially modifiable environmental factors which might operate in infancy is of importance. The present findings implicate infant bedding choice as a significant factor and further studies on the infant sleeping environment are indicated.

Objective: To examine independent associations of job strain (high demands and low control) and job insecurity with mental and physical health outcomes. Design: Cross sectional general population study conducted in 2000 using a self completed questionnaire. Setting: Two adjoining cities in south east Australia. Subjects: 1188 employed professionals, aged 40–44 years, 55% (n = 655) male. Main outcome measures: Depression, anxiety, physical, and self rated health (SRH). Results: Adverse job conditions were relatively prevalent as 23% of the sample reported high job strain, while 7.3% and 23% reported high and moderate job insecurity respectively. Associations between job conditions and health persisted after adjustment for gender, education, marital status, employment status, major life events, and negative affectivity (personality). When adjusted for job strain, high job insecurity was independently associated with a greater than threefold increase in odds for poor SRH, depression and anxiety (OR (95% confidence intervals) poor SRH: 3.72 (1.97 to 7.04) depression: 3.49 (1.90 to 6.41), anxiety: 3.29 (1.71 to 6.33)), and a twofold increase for physical health 2.19 (1.21 to 3.95). High job strain also showed significant independent associations with depression: 2.54 (1.34 to.4.75) and anxiety: 3.15 (1.48 to 6.70). Conclusion: In this relatively privileged socioeconomic group, insecure employment and high job strain showed independent, consistent, and strong associations with physical and mental health. These adverse job conditions are on the increase, particularly insecure employment, and the influence of these two work conditions are an important focus for future public health research and their prevalence and impact should be examined in other occupations.

The apparent immune-suppressive effect of ultraviolet radiation (UVR) has suggested that this environmental exposure may influence the development of immune-related disorders. Self-reported prevalence rates of type 1 diabetes mellitus, rheumatoid arthritis (RA), eczema/dermatitis, and asthma, from the 1995 Australian National Health Survey, were therefore examined by latitude and ambient level of UVR. A positive association of type 1 diabetes mellitus prevalence was found with both increasing southern latitude of residence (r = 0.77; p = 0.026) and decreasing regional annual ambient UVR (r= -0.80; p = 0.018); a 3-fold increase in prevalence from the northernmost region to the southernmost region was evident. In contrast, asthma correlated negatively with latitude (r = -0.72; p = 0.046), although the change in asthma prevalence from the north to the south of Australia was only 0.7-fold. For both RA and eczema/dermatitis, there were no statistically significant associations between latitude/UVR and disease prevalence. These ecologic data provide some support for a previously proposed beneficial effect of UVR on T-helper 1-mediated autoimmune disorders such as type 1 diabetes. The inverse association of type 1 diabetes prevalence with UVR is consistent with that previously reported for another autoimmune disease, multiple sclerosis, in Australia, and also with type 1 diabetes latitudinal gradients in the Northern Hemisphere. The finding also accords with photoimmunologic evidence of UVR-induced immunosuppression and may suggest a beneficial effect of UVR in reducing the incidence of such autoimmune conditions. In light of this study, analytic epidemiologic studies investigating risk of immune disorders in relation to personal UVR exposure in humans are required.

Our aim was to examine the relative importance of family size on sensitization to two different allergens: ryegrass and house dust mite (HDM), using a mutually exclusive classification for allergen-specific sensitization. An 8-year follow-up birth cohort study of children born between 1988-89 was conducted. The follow-up sample consisted of 498 children residing in Northern Tasmania in 1997 (84% of eligible). Outcome measures included skin prick test (SPT) reaction to nine aeroallergens and parental questionnaire. Family size was defined as sibling number in 1997. Children with a positive SPT to either Der p or Der f house dust mite but not ryegrass were classified as HDM-exclusive (n = 84). Children with a positive SPT to ryegrass but not HDM were classified as ryegrass-exclusive (n = 43). Family size was associated with reduced ryegrass-exclusive sensitization [AOR 0.57 (0.39, 0.84) per increase in sibling number] but not HDM-exclusive sensitization [AOR 0.97 (0.77,1.23)]. The difference in the family size effect on these sensitization outcomes was significant (p = 0.02). Similarly, family size tended to be associated with reduced asthma among ryegrass-exclusive sensitized children [AOR 0.45 (0.18,1.12)] but not HDM-exclusive sensitized children [(AOR 1.46(0.80-2.65)]. Large family size was strongly associated with reduced sensitization for ryegrass allergens but not HDM allergens using mutually exclusive sensitization categories. If this difference is confirmed in other studies, the contrasting effect of family size may reflect differences between these allergens with regard to level or timing of early life exposure, differences in allergen -specific potentiation for sensitization or unidentified confounding. The use of mutually exclusive categories for allergen sensitization will assist future work on child atopic disease.

Summary Background Higher house dust mite (HDM) allergen exposure during infancy has been associated with increased HDM sensitization. Infant bedding has been associated with the accumulation of varying levels of HDM. Prospective data on the relationship between infant bedding and the development of HDM sensitization has not been previously examined. Objectives To determine if particular types of bedding used in infancy are associated with increased risk of house dust mite sensitization in childhood. Methods A population-based sample (n = 498) of children born in 1988 or 1989, and who were resident in Northern Tasmania in 1997, participated in this study. These children were part of a birth cohort study (1988–95), the Tasmanian Infant Health Survey. Data on infant underbedding and mattresses was available on 460 and 457 children, respectively. The main outcome measure was HDM sensitization defined as a skin prick test (SPT) reaction of 3 mm or more to the allergens of Dermatophagoides pteronyssinus and/or Dermatophagoides farinae. Results The use of either sheepskin underbedding or plastic mattress covers in infancy was associated with an increased risk of sensitization to HDM allergens at age 8 years. The adjusted risk ratio (RR) for sensitization to HDM with sheepskin in infancy was 2.27 (95% CI: 1.14, 4.55), P = 0.020. The adjusted RR for sensitization to HDM with the use of plastic mattress covers in infancy was 2.06 (95% CI: 1.22, 3.51), P = 0.007. The use of a foam mattress in infancy was not related to subsequent HDM sensitization. Conclusion Infant's bedding plays a role in the development of HDM sensitization in childhood. Intervention studies to examine mite allergen levels and the role of underbedding on the development of HDM sensitization are required.

Objective: To report reference data for the heart-specific MacNew Heart Disease Health-Related Quality of Life instrument. Methods: One thousand five hundred and six patients with myocardial infarction (n = 346), heart failure (n = 201), and ischaemic heart disease (IHD, n = 959) were surveyed 4 months after hospital discharge. Quality of life scores were determined, stratified by diagnostic category, age and sex. Changes in scores from 4 to 8 months post-discharge were calculated for a subset of 830 patients, stratified by age and sex. Results: At 4 months there were no significant differences in scores between myocardial infarction and electively admitted IHD patients, however the scores of heart failure patients were significantly lower (indicating poorer quality of life) than those of patients with other diagnoses. There were few significant differences between age groups or sexes when comparing within diagnostic groups. Change from 4 to 8 months was not associated with diagnosis, age, or sex but was associated with events within the period (readmission or revascularisation). The change data suggest that a value of 0.5 may be a useful indicator of the minimal clinically important difference. Conclusions: These reference data will assist in sample size calculations and with comparison of results in other studies, and will be of use to researchers who are using or intending to use the MacNew instrument.

A sample of 945 cardiac patients admitted under emergency conditions completed a quality of life questionnaire 4 months post-discharge. Half (471) were randomly allocated to a group used to develop a logistic regression model to predict mortality and cardiovascular morbidity 8 months later. Age 65-85 years, ever having heart failure, experiencing another cardiovascular event since discharge, and low global quality of life (QOL) score were found to be predictive of these outcomes; an interaction between QOL and heart failure was also found. The model was used to formulate a risk index which was validated in the remaining 474 patients. The index defines four levels of increasing risk of adverse outcomes, with rates in the development and validation groups, respectively, of: low risk 4% and 9%; moderate risk 13% and 15%; high risk 31% and 33%; very high risk 52% and 40%. Scores in the emotional, physical and social QOL domains were also found to be predictive of adverse outcomes, suggesting that interventions in any of these areas may prove beneficial. The index may be useful for follow-up evaluation of cardiac patients.

The objective of this study was to develop a simplified scoring system to predict 30-day mortality in patients with acute ischemic stroke. A retrospective cohort study was performed in a tertiary referral hospital in the Hunter Region of Australia. A prognostic index was created by assigning points to the variables in a Cox model. The index included impaired consciousness (5 points), dysphagia (3 points), urinary incontinence (4 points), admission body temperature higher than 36.5 degrees C (2 points), and hyperglycemia without a clinical history of diabetes (2 points). A score of 11 or more defined a high-risk group. The index achieved a sensitivity, specificity, and positive predictive value of 68%, 98% and 75%, respectively, in the derivation sample and 57%, 97% and 68%, respectively, in the validation sample. The results provide a simple risk stratification instrument for clinical research and practice. Further evaluation of the model in a prospective cohort is warranted

STUDY OBJECTIVE—To examine the hospital management of unstable angina (UAP) in 1996 and 1998, according to patient demographic variables and disease severity. DESIGN—Medical record review. SETTING—37 hospitals across New South Wales, Australia, representative of the secondary and tertiary care hospitals in the State. PARTICIPANTS—All patients (or a random sample of patients) with UAP admitted to these hospitals during five months in 1996 and six months in 1998 (1872 and 1368 patients respectively). MAIN RESULTS—In the two years between 1996 and 1998, there was an increase in the use of β blockers and a corresponding decrease in the use of calcium channel blockers, as well as a decrease in the use of intravenous nitrates. Those aged 75 or more were roughly half as likely as those aged less than 65 to be prescribed heparin, aspirin and heparin, β blockers, intravenous nitrates, and only one third as likely to be offered coronary angiography in hospital. They were one and a half times as likely to be prescribed calcium channel blockers compared with the youngest age group. A similar pattern was seen for gender, where men were more likely than women to be given aspirin, aspirin and heparin, and coronary angiography, and less likely to be given calcium channel blockers. Those with a past history were less likely, and those with more severe disease were more likely than others to be given most interventions. CONCLUSIONS—In view of the low use of evidence-based management of UAP among women and the elderly, it would seem appropriate for disease management guidelines to target these groups. Keywords: unstable angina; management; trends

The objective of this study was to determine the accuracy of administrative data (by use of hospital discharge codes) for measuring comorbidity in patients with heart disease. One thousand seven hundred and sixty-five medical records of subjects admitted to hospital for AMI, unstable angina, angina pectoris, chronic IHD or heart failure were reviewed. The number and types of comorbidities were determined from the medical records (regarded as the "gold standard"). These were compared with the 10 discharge codes obtained from the hospital administrative records (referred to as the "administrative data"). The rate of false-negative and false-positive comorbidity diagnoses were determined. Twenty of the 21 comorbidities studied were underreported in the administrative data. For these 20 comorbidities, the median false-negative rate was 49.5% and ranged from 11% for diabetes to 100% for dementia. False-positive rates were low, less than 1.5%, except for chronic arrythmia (4.8%) and hypertension (4.2%). Mean percent agreement was high, ranging from 88% for hypertension to 100% for AIDS/HIV. Administrative data based on hospital discharge codes consistently underestimate the presence of comorbid conditions in our population. This has implications for administrators when estimating mortality, length of stay and disability. Researchers also need to be aware when using administrative data based on hospital discharge codes to assess subject's comorbidities that they may be widely underreported.

The influence of hyperglycemia on stroke mortality is controversial. The aim of this study was to investigate the prognostic role of hyperglycemia and diabetes on short-term and long-term mortality in patients with acute ischemic stroke.This retrospective cohort study included 416 acute ischemic stroke patients admitted to a tertiary hospital between July 1, 1995 and June 30, 1997. In-hospital mortality and 1-year mortality after discharge were the outcomes of the study. All patients were classified into four groups according to the glucose status and history of diabetes: group 1, normoglycemic without diabetes; group 2, normoglycemic with diabetes; group 3, hyperglycemic with diabetes and group 4, hyperglycemic without diabetes. Cochrane-Armitage trend test was used to assess the trend of mortality across the 4 groups. The influence of hyperglycemia on in-hospital and 1-year mortality were studied by logistic regression and Cox proportional hazards regression adjusting for confounders.The Cochrane-Armitage trend test showed there was a strong trend towards increasing in-hospital mortality across groups 1 to 4 (P.001). Hyperglycemia without a history of diabetes was an independent predictor of in-hospital mortality, odds ratio 3.0 (95% confidence interval: 1.1-8.3; P = .035). Hyperglycemia (with or without diabetes) did not predict in-hospital mortality significantly. Neither hyperglycemia per se nor hyperglycemia without a history of diabetes were significant in predicting 1-year mortality.Hyperglycemia without diabetes is independently associated with higher in-hospital mortality in patients with acute ischemic stroke. There was a trend to increasing in-hospital mortality across groups 1 to 4.

There are few data on the practice of evidence based medicine in the developing world, nor on the actual sources of evidence that clinicians use in practice. To test the hypothesis that there was variation between and within developing countries in the proposed management of a patient with hospital acquired pneumonia, and that part of the variation can be explained by the sources of evidence used. Questionnaire responses to hypothetical case history. Investigators from 6 centres within the International Clinical Epidemiology Network (INCLEN) in China, Thailand, India, Egypt, and Kenya. Doctors chosen to represent primary and secondary hospital practice in the regions of the study centres. Investigations and initial treatments which would be ordered for a hypothetical 60-year-old woman who develops pneumonia 5 days after hospital admission, whether local data on antibiotic sensitivities are available and where information would be obtained to guide management. Chest x-ray and sputum gram stain/culture were consistently the most commonly ordered investigations, there being much greater variation in the initial treatment choices with either penicillin, a third-generation cephalosporin or aminoglycoside being the most popular choice. Textbooks were the commonest form of information source, and access to a library, textbooks and journals were statistically significantly associated with appropriate choice of investigations, but not treatment. Access to local antibiotic sensitivities was associated with appropriate initial treatment choice. Improving access to information in the literature and to local data may increase the practice of evidence-based medicine in the developing world.

To examine the variation in stated management of acute myocardial infarction (AMI) among clinicians of different specialties, and to compare stated with actual practice.Mail survey using a hypothetical case history, and review of medical records.47 public hospitals in New South Wales.224 cardiologists, general/other physicians and general practitioners (GPs) who manage patients with AMI; 390 patients admitted for AMI between February and June 1996.Stated and actual use of treatments and investigations for AMI.Stated use of aspirin, thrombolysis and beta-blockers (95%-100%, 95%-100% and 80%-86%, respectively) was high in all three specialties. Cardiologists were significantly more likely than GPs to state use of heparin (87% v 57%; P0.001), ACE inhibitors (84% v 49%; P0.001) and echocardiography or gated pool heart scan (79% v 26%; P0.001). Stated use of nitrates by cardiologists was significantly lower compared with the other specialties (29% v 50% and 44%; P = 0.027). Actual use of aspirin was high (80%) in all specialties. Actual use of thrombolysis was similar to stated use after adjusting for factors such as time to hospital arrival and ST-segment elevation. There were substantial differences between stated and actual use.There were differences in practice patterns between and among clinicians of different specialties in NSW, consistent with findings from other countries. The high stated and actual use of aspirin and thrombolysis is encouraging.

Many extensions of survival models based on the Cox proportional hazards approach have been proposed to handle clustered or multiple event data. Of particular note are five Cox-based models for recurrent event data: Andersen and Gill (AG); Wei, Lin and Weissfeld (WLW); Prentice, Williams and Peterson, total time (PWP-CP) and gap time (PWP-GT); and Lee, Wei and Amato (LWA). Some authors have compared these models by observing differences that arise from fitting the models to real and simulated data. However, no attempt has been made to systematically identify the components of the models that are appropriate for recurrent event data. We propose a systematic way of characterizing such Cox-based models using four key components: risk intervals; baseline hazard; risk set, and correlation adjustment. From the definitions of risk interval and risk set there are conceptually seven such Cox-based models that are permissible, five of which are those previously identified. The two new variant models are termed the 'total time - restricted' (TT-R) and 'gap time - unrestricted' (GT-UR) models. The aim of the paper is to determine which models are appropriate for recurrent event data using the key components. The models are fitted to simulated data sets and to a data set of childhood recurrent infectious diseases. The LWA model is not appropriate for recurrent event data because it allows a subject to be at risk several times for the same event. The WLW model overestimates treatment effect and is not recommended. We conclude that PWP-GT and TT-R are useful models for analysing recurrent event data, providing answers to slightly different research questions. Further, applying a robust variance to any of these models does not adequately account for within-subject correlation.

This study aims to determine whether the Charlson comorbidity index computed from ICD-9-CM discharge diagnosis codes adds additional information to a model containing adjustment for more informed patient details (e.g., disease severity and history), besides solely age and sex, when predicting long-term survival. We conducted a retrospective cohort study of patients admitted to hospital for suspected acute myocardial infarction. Index scores were calculated by applying the D’Hoore et al. algorithm (1993). The index significantly improved the model fit (likelihood ratio test: p

Objectives: To test the hypothesis that among patients with acute myocardial infarction (AMI) length of hospital stay, drug use in hospital and on discharge were different between metropolitan and regional hospitals after adjusting for differences in patient baseline risk. Methods: A retrospective cohort study using a community-based register of heart attack patients assessed 1,406 patients admitted for definite AMI to three metropolitan and five regional hospitals in the Lower Hunter Region of NSW, between January 1,1990, and March 31,1994. Results: Patients in metropolitan hospitals were significantly less likely to stay in hospital for more than seven days (adjusted odds ratio=0.50; 95% CI 0.34-0.73), significantly more likely to receive ACE inhibitors (adj.OR=1.47; 1.27-1.71) and less likely to receive calcium channel blocker (adj.OR=0.70; 0.54-0.98). Regardless of disease severity, metropolitan hospitals had a higher percentage of patients for whom drugs shown to decrease mortality after AMI were used (streptokinase, aspirin, ACE inhibitor); a lower percentage of patients received drugs shown to have no benefit or even a detrimental effect (calcium channel blocker). Both groups had relatively low use of beta blocker, also shown to be of benefit. Conclusions: Regional hospitals had longer hospital stays than metropolitan hospitals and less use of drugs of proven benefit.

Objective: To determine the pooled relative risk (RR) of prophylactic ondansetron relative to droperidol and relative to metoclopramide for prevention of post-operative (p.o.) vomiting in children.Design: Meta-analysis of published randomised trials of p.o. emesis.Study Selection: Of 22 articles reviewed in detail by the three authors, 19 met the eligibility criteria. The meta-analysis of ondansetron versus droperidol included 13 studies. The metoclopramide meta-analysis included 8 studies.Main Outcome: P.O. vomiting over a 24-hour period.Results: There were consistent statistically significant benefits of ondansetron compared with droperidol (pooled RR 0.67, 95% confidence interval 0.49-0.90, p=0.0092) and with metoclopramide (0.56, 0.44-0.71, p

Objective: To determine the pooled relative risk (RR) of prophylactic ondansetron relative to metoclopramide and relative to droperidol for prevention of post-operative (p.o.) vomiting in adults.Design: Meta-analysis of published randomised trials of p.o. emesis.Study Selection: Of 33 articles reviewed in detail by the three authors, 25 met the eligibility criteria. The meta-analysis of ondansetron versus metoclopramide included 16 studies. The droperidol meta-analysis included 13.Main Outcome: p.o. vomiting over a 24-hour period.Results: There was no clear benefit of ondansetron compared with metoclopramide (pooled RR 0.74, 95% confidence interval 0.54-1.00, p=0.051) or with droperidol (pooled RR 0.91, 95% CI 0.65-1.29, p=0.61). The heterogeneity seen among the metoclopramide studies was explained by type of surgery (major gynaecological, minor gynaecological or non-gynaecological) and duration of outcome assessment (

This study tests the hypothesis that it is possible to predict people who will have a low quality of life (QOL) 6 months after hospital admission for acute myocardial infarction (AMI) or angina. Among 424 patients discharged from hospital in the Hunter Region of New South Wales with a diagnosis of AMI or angina, follow-up questionnaires were received from 303 at 6 months. Baseline data collected during hospitalisation included demographic variables and the 'emotional' factor of a disease-specific QOL measure using a modified and validated self-administered questionnaire. The full QOL measure comprises 'emotional', 'physical' and 'social' factors, each factor being assessed at the 6-month follow-up. Only baseline 'emotional' QOL score and sex predicted 6-month QOL scores in patients with AMI. Scores were consistently lower in patients with angina, in whom marital and employment status, having had a previous AMI, current cigarette smoking, the presence of cardiac failure and baseline emotional QOL were all significantly associated with the 6-month QOL scores. The assessment of simple measures during hospitalisation for angina can be helpful in predicting those who will have a low QOL 6 months later. They may represent a high-risk group at whom counselling could be directed.

Introduction Sugar sweetened beverages (SSBs) are implicated in the rising prevalence of obesity and diet-related chronic diseases worldwide. However, little is known about their contribution to weight gain in Asian populations. This study aimed to investigate weight change associated with SSB consumption between 2005 and 2009 in a large national cohort of Thai university students. Methods Questionnaire data were collected from a large Thai cohort (the Thai Health-Risk Transition: a National Cohort Study). The analysis was based on responses from 59 283 of the 60 569 (98%) cohort members who had valid SSB consumption and weight variables in 2005 and 2009. The relationship between SSB consumption in 2005 and self-reported weight change was analysed using multiple linear regression models controlled for socio-demographic, activity and (non-validated) dietary factors shown to influence weight. Results Higher frequency of SSB consumption in 2005 was significantly associated with greater weight gain between 2005 and 2009 in all age groups and in both sexes (p once per day) between 2005 and 2009 compared to those who maintained it was 0.3 kgs, while persons who reduced their consumption frequency (once a day to > once a month) gained 0.2 kgs less than those whose consumption remained unchanged. Conclusion SSB consumption is independently associated with weight gain in the Thai population. Research and health promotion in Thailand and other economically transitioning countries should focus on reducing their contribution to population weight gain and to diet-related chronic diseases.

BACKGROUND From 5 to 12 January 1994, the state of New South Wales suffered from the worst bushfires seen this century. High levels of particulate air pollution were recorded in western Sydney from 7 to 14 January 1994, with nephelometry readings reaching 10.24 beta scat (10(-4)/m) and particulate matter < 10 mu readings peaking at 250.00 micrograms/m3. The aim of this study was to determine whether there was an increase in the proportion of asthma presentations to emergency departments (ED) in western Sydney as a result of the bushfire-generated particulate air pollution. METHOD We retrospectively analysed the emergency room attendance books for asthma presentations from seven public hospitals serving the Western Sydney and Wentworth Health Areas over two 6-7 week periods, 17 December 1992 to 31 January 1993, and 17 December 1993 to 31 January 1994. Air pollution and meteorological data were obtained from local monitoring stations. RESULTS The difference in the proportion of all ED presentations that were due to asthma during the week of the bushfire-generated air pollution, compared with the same week 12 months before, after adjusting for baseline changes over the 12-month period, was 0.0067 (95% CI: -0.0007, 0.0141). The maximum daily nephelometry reading was not a significant predictor of the daily number of asthma presentations to ED in any of the Poisson regression models. CONCLUSIONS The bushfire-generated particulate air pollution in January 1994 did not result in an increase in asthma presentations to ED in western Sydney.

Erythocyte mean corpuscular volume (MCV) rises dramatically in the presence of zidovudine, which currently is the only anti-retroviral licensed for the treatment of HIV infected individuals. This paper reports the long-term effects of zidovudine on MCV levels and discusses the potential for using MCV levels as a measure of compliance to study medication in clinical trials of zidovudine.

We examine the influence of urbanization on household structure, social networks, and health in Thailand. We compare lifetime urban or rural dwellers and those who were rural as children and urban as adults. Data derived from a large national cohort of 71,516 Sukhothai Thammathirat Open University adult students participating in an on-going longitudinal study of the health-risk transition in Thailand. The rural-urban group, one-third of cohort households, was significantly different from other groups (e.g., smaller households). The rural-rural and the urban-urban groups often were the two extremes. Urbanization, after adjusting for covariates, was a risk factor for poor overall health and depression. Urbanization is a mediator of the health-risk transition underway in Thailand. Health programs and policies directed at transitional health outcomes should focus on the health risks of the urbanizing population, in particular smoking, drinking, low social trust, and poor psychological health.

A slightly modified version of the Quality-of-Life after Myocardial Infarction (QLMI) questionnaire developed by Oldridge and colleagues was applied in a self-administered mode to patients with suspected acute myocardial infarction (AMI) in a randomized controlled trial of secondary prevention. Acceptability of the questionnaire was good, with 93% of responders answering all items. Factor analysis suggested three quality-of-life (QL) dimensions which we called "emotional", "physical" and "social". These differed somewhat from the dimensions proposed by Oldridge and colleagues. However, a sensitivity analysis showed relative invariance of results to weighting schemes. Scores on our three dimensions were responsive to differences between the treatment groups, and demonstrated construct validity based on associations between the measured QL and variables expected to affect QL. We conclude that the QLMI questionnaire has good potential as an instrument for assessing QL in post-AMI patients and that it can be successfully self-administered.

There are limited data on the frequency of foregone health service use in defined populations. Here we describe Thai patterns of health service use, types of health insurance used and reports of foregone health services according to geo-demographic and socioeconomic characteristics. Data on those who considered they had needed but not received health care over the previous year were obtained from a national cohort of 87,134 students from the Sukhothai Thammathirat Open University (STOU). The cohort was enrolled in 2005 and was largely made up of young and middle-age adults living throughout Thailand. Among respondents, 21.0% reported use of health services during the past year. Provincial/governmental hospitals (33.4%) were the most attended health facilities in general, followed by private clinics (24.1%) and private hospitals (20.1%). Health centers and community hospitals were sought after in rural areas. The recently available government operated Universal Coverage Scheme (UCS) was popular among the lower income groups (13.6%), especially in rural areas. When asked, 42.1% reported having foregone health service use in the past year. Professionals and office workers frequently reported 'long waiting time' (17.1%) and 'could not get time off work' (13.7%) as reasons, whereas manual workers frequently noted it was 'difficult to travel' (11.6%). This information points to non-financial opportunity cost barriers common to a wide array of Thai adults who need to use health services. This issue is relevant for health and workplace policymakers and managers concerned about equitable access to health services.

Background Decomposition of concentration indices yields useful information regarding the relative importance of various determinants of inequitable health outcomes. But the two estimation approaches to decomposition in current use are not suitable for binary outcomes. Findings The paper compares three estimation approaches for decomposition of inequality concentration indices: Ordinary Least Squares (OLS), probit, and the Generalized Linear Model (GLM) binomial distribution and identity link. Data are from the Thai Health and Welfare Survey 2003. The OLS estimates do not take into account the binary nature of the outcome and the probit estimates depend on the choice of reference groups, whereas the GLM binomial identity approach has neither of these problems. Conclusions The GLM with binomial distribution and identity link allows the inequality decomposition model to hold, and produces valid estimates of determinants that do not vary according to choice of reference groups. This GLM approach is readily available in standard statistical packages.

Background Large-scale epidemiological studies commonly use self-reported weights and heights to determine weight status. Validity of such self-reported data has been assessed primarily in Western populations in developed countries, although its use is widespread in developing countries. We examine the validity of obesity based on self-reported data in an Asian developing country, and derive improved obesity prevalence estimates using the "reduced BMI threshold" method. Methods Self-reported and measured heights and weights were obtained from 741 students attending an open university in Thailand (mean age 34 years). Receiver operator characteristic techniques were applied to derive "reduced BMI thresholds." Results Height was over-reported by a mean of 1.54 cm (SD 2.23) in men and 1.33 cm (1.84) in women. Weight was under-reported by 0.93 kg (3.47) in men and 0.62 kg (2.14) in women. Sensitivity and specificity for determining obesity (Thai BMI threshold 25 kg/m2) using self-reported data were 74.2% and 97.3%, respectively, for men and 71.9% and 100% for women. For men, reducing the BMI threshold to 24.5 kg/m2 increased the estimated obesity prevalence based on self-reports from 29.1% to 33.8% (true prevalence was 36.9%). For women, using a BMI threshold of 24.4 kg/m2, the improvement was from 12.0% to 15.9% (true prevalence 16.7%). Conclusion Young educated Thais under-report weight and over-report height in ways similar to their counterparts in developed countries. Simple adjustments to BMI thresholds will overcome these reporting biases for estimation of obesity prevalence. Our study suggests that self-reported weights and heights can provide economical and valid measures of weight status in high school-educated populations in developing countries.

Poor health-related quality of life (HRQL) has been shown to be predictive of adverse outcomes in cardiac patients. As women with coronary heart disease have been shown to have lower HRQL than men with coronary heart disease, women are at greater risk of a poor clinical outcome. This study tested the effect of a 12-week home walking intervention after completion of outpatient cardiac rehabilitation (OCR) on HRQL and maintenance of physical activity among women.Multicenter two-group randomized trial.After completion of OCR, participants were randomly allocated to the intervention or usual care groups. The outcomes were HRQL (assessed using the MacNew Heart Disease HRQL instrument) and self-reported physical activity (assessed using the Stages of Change model of exercise behavior) at 3, 6, and 12 months after OCR.Seventy-two women were randomized to the intervention and 81 to usual care. Attrition was greater in the treatment group (13 vs. 1%). HRQL scores increased relative to the base level in both arms and were significantly higher in the intervention group at 6 months, but not at 3 or 12 months. Maintenance of physical activity declined over time in both groups, however, this decline was significantly reduced among women in the intervention group.HRQL improved in both groups, but seemed to increase earlier among women in the intervention group. As maintenance of physical activity was higher among women in the intervention group, this minimal intervention could be used to facilitate women's progression from supervised to independent exercise.

Background: Thailand is undergoing a health-risk transition with overweight and obesity emerging as an important population health problem. This paper reports on a study of the transition, focusing on "lifestyle" factors such as diet (fried foods, soft drinks, Western-style fast foods) and physical activity (mild, moderate, strenuous exercise, housework/gardening and screen time). Methods: A baseline survey was administered to 87 134 adult students from all regions of Thailand attending an open university. Results: 54% of the cohort was female. Participants' median age was 29 years. By self-reported Asian standards, 16% of the sample was obese (body mass index (BMI)≥25) and 15% overweight at risk (BMI≥23-24.9). Men were twice as likely as women to be overweight (21% vs 9%) or obese (23% vs 10%). Obesity was associated with urban residence and doing little housework or gardening and with spending more than 4 hours a day watching television or using computers. The latter occurred among 30% of the cohort, with a population attributable fraction (PAF) suggesting that it accounts for 11% of the current problem. Daily consumption of fried food was associated with obesity, and eating fried foods every second day or daily had a PAF of nearly 20%. Conclusions: These health-related behaviours underpinning the Thai health transition are associated with increasing obesity. They are modifiable through policies addressing structural issues and with targeted health promotion activities to prevent future obesity gains. Insights into future trends in the Thai health transition can be gained as this student cohort ages.

Background Since its translation to Thai in 2000, the SF-36 Health Survey has been used extensively in many different clinical settings in Thailand. Its popularity has increased despite the absence of published evidence that the translated instrument satisfies scoring assumptions, the psychometric properties required for valid interpretation of the SF-36 summated ratings scales. The purpose of this paper was to examine these properties and to report on the reliability and validity of the Thai SF-36 in a non-clinical general population. Methods 1345 distance-education university students who live in all areas of Thailand completed a questionnaire comprising the Thai SF-36 (Version 1). Median age was 31 years. Psychometric tests recommended by the International Quality of Life Assessment Project were used. Results Data quality was satisfactory: questionnaire completion rate was high (97.5%) and missing data rates were low (< 1.5% for all items). The ordering of item means within scales generally were clustered as hypothesized and scaling assumptions were satisfied. Known groups analysis showed good discriminant validity between subgroups of healthy persons with differing health states. However, some areas of concern were revealed. Possible translation problems of the Physical Functioning (PF) items were indicated by the comparatively low ceiling effects. High ceiling and floor effects were seen in both role functioning scales, possibly due to the dichotomous format of their response choices. The Social Functioning scale had a low reliability of 0.55, which may be due to cultural differences in the concept of social functioning. The Vitality scale correlated better with the Mental Health scale than with itself, possibly because a healthy mental state is central to the concept of vitality in Thailand. Conclusion The summated ratings method can be used for scoring the Thai SF-36. The instrument was found to be reliable and valid for use in a general non-clinical population. Version 2 of the SF-36 could improve ceiling and floor effects in the role functioning scales. Further work is warranted to refine items that measure the concepts of social functioning, vitality and mental health to improve the reliability and discriminant validity of these scales.

Objectives. We investigated the role of infant bedding items, as part of a composite bedding environment, in the development of childhood wheezing. Methods. This prospective cohort investigation involved 863 children who participated in an infant survey in 1988 and an asthma study in Tasmania, Australia, in 1995. The derived 3 composite infant bedding categories corresponded to increasing numbers of house dust mite (HDM)–rich bedding items used. Outcomes measured included recent and frequent wheezing. Results. Composite infant bedding used was associated with recent wheezing. Effects increased at increasing levels of HDM–rich bedding items used. Effects were further enhanced by home environmental factors of bedroom heating, recent bedroom painting, and absence of bedroom carpeting. When any 2 or more of these environmental factors were present, a strong dose–response relationship was evident. Conclusions. Our results show that bedding exposures in infancy are prospectively associated with childhood wheezing and that home environmental conditions may modify this association.

Family life in developed economies has undergone a fundamental change—shifting from single-breadwinner households (typical of the post war decades) to families where both parents are employed. Equally dramatic has been the emergence of around-the-clock economies, altering the way work is organised, especially working time. Many more children now live in households where one or both parents work non-standard hours (evenings, nights or on weekends). Are there any implications for children's well-being when parents work non-standard schedules? There has been virtually no investigation of how children are faring in these around-the-clock households, despite evidence that non-standard work times affect family functioning and are stressful for parents. Using data from a representative sample of 4433 dual-earner Canadian families and their 2–11-year-old children (N children=6361), we compared families where both parents worked standard hours, with families where one or both worked non-standard times (evenings, nights or weekends). In nearly three-quarters of the families one or both parents regularly worked non-standard times. We found associations between children's well-being and parent work schedules, with higher odds ratios for child difficulties when parents worked non-standard times. These associations persisted after adjusting for several confounding factors including socio-economic status, parent part-time or full-time work, and childcare use, and were evident whether mothers, fathers or both parents worked non-standard times. The findings raise questions about the implications for children of the 24-h economy.

To develop a prediction model for 1-year mortality in patients with acute ischemic stroke, with the model to be at least as useful and accurate as other previously developed prediction models.Retrospective cohort study.Neurology department at an Australian tertiary teaching hospital.Four hundred forty consecutive patients diagnosed with acute ischemic stroke between July 1, 1995, and June 30, 1997.Two hundred twenty-three (51%) patients were randomly assigned to the derivation sample to develop a prediction model using the Cox proportional hazards model. The model was then validated in a validation sample of 217 (49%) patients.One-year mortality.Eight clinical predictors were included in the final model: unconsciousness (3 points), dysphagia (7 points), urinary incontinence (9 points), both sides affected (4 points), hyperthermia (4 points), ischemic heart disease (3 points), peripheral vascular disease (3 points), and diabetes mellitus (2 points). Patients with scores of 10 or higher were allocated to the high-risk group, which had a 1-year mortality rate of 76%, compared with a 1-year mortality rate of 8% in the low-risk group. There was no statistically significant difference in terms of sensitivity, specificity, and positive predictive value in the validation sample.We developed a predictive model for 1-year mortality in acute ischemic stroke patients. The model is easy to use and is comparable in its accuracy with other predictive models.

Objective: To describe the health of the Australian workforce in relation to occupational status. Methods: Data on 9,167 workers, collected between 1998 and 2001, were obtained from the Campbell National Health Monitor(tm), a cross-sectional national health survey. Professional, white-collar and blue-collar workers were compared on five health outcomes: self-rated health, long-and short-term conditions, reduced activity days and work absences. Results: One in 10 workers (M:11 %; F:10%) rated their health as poor. Two-thirds (M: 60%; F: 64%) reported long-term conditions with four in five (M:77%; F: 83%) reporting short-term conditions. Smaller proportions took health-related actions, with 21% of men and 28% of women reducing their activity, and 17% of men and 20% of women taking time off work in a given month. Occupational inequalities in self-rated health were evident for both men and women, with professionals reporting the best health and blue-collar workers the worst (p < 0.001). Male, but not female, white and blue-collar workers also had higher rates of short-term conditions (OR 1.25, 1.06–1.50 and 1.25, 1.07–1.46, respectively) and reduced activity days due to health (OR 1.43, 1.20–1.71 and 1.25, 1.07–1.47, respectively) compared with professionals. However, blue-collar workers reporting health problems were the least likely to take time off work (poor health: p=0.043; short-term conditions: p=0.001; long-term conditions: p=0.003). Conclusions and implications: Blue-collar workers are the least healthy occupational grouping. They are also the most likely to present to work unwell. With employment conditions rapidly changing, better understanding of the impact of these changes on workers' health is vital.

Background Little is known about the influence of the site of research or publication on the impact of the research findings on clinical practice, particularly in developing countries. The International Clinical Epidemiology Network (INCLEN) is dedicated to improving the quality of health research in the Developing World through institutional capacity building for evidence based medicine, and provided the opportunity to examine the likely impact of research location and journal location on physicians' practice in a number of the participating countries. Methods Physicians from secondary and tertiary hospitals in six cities located in China, Thailand, India, Egypt and Kenya were enrolled in a cross-sectional questionnaire survey. The primary outcome measures were scores on a Likert scale reflecting stated likelihood of changing clinical practice depending on the source of the research or its publication. Results Overall, local research and publications were most likely to effect change in clinical practice, followed by North American, European and regional research/publications respectively, although there were significant variations between countries. The impact of local and regional research would be greater if the perceived research quality improved in those settings. Conclusion Conducting high quality local research is likely to be an effective way of getting research findings into practice in developing countries.

To report reference data for the heart-specific MacNew Heart Disease Health-Related Quality of Life instrument.One thousand five hundred and six patients with myocardial infarction (n = 346), heart failure (n = 201), and ischaemic heart disease (IHD, n = 959) were surveyed 4 months after hospital discharge. Quality of life scores were determined, stratified by diagnostic category, age and sex. Changes in scores from 4 to 8 months post-discharge were calculated for a subset of 830 patients, stratified by age and sex.At 4 months there were no significant differences in scores between myocardial infarction and electively admitted IHD patients, however the scores of heart failure patients were significantly lower (indicating poorer quality of life) than those of patients with other diagnoses. There were few significant differences between age groups or sexes when comparing within diagnostic groups. Change from 4 to 8 months was not associated with diagnosis, age, or sex but was associated with events within the period (readmission or revascularisation). The change data suggest that a value of 0.5 may be a useful indicator of the minimal clinically important difference.These reference data will assist in sample size calculations and with comparison of results in other studies, and will be of use to researchers who are using or intending to use the MacNew instrument.

An observational cohort study examined the difference in use of cardiac procedures during and after hospital admission for acute chest pain in 47 metropolitan or non-metropolitan hospitals across New South Wales (NSW). There were 3836 patients, represented by 4151 admissions to hospital after acute myocardial infarction (AMI), unstable angina or other angina. Follow up at 22 months was completed on 1695 patients. Patients admitted to metropolitan hospitals had higher rates of most cardiac procedures while in-patients than did patients in non-metropolitan hospitals. Odds ratios (95% confidence intervals) for the use of exercise stress tests, echocardiograms, nuclear studies and coronary angiography were 3.30 (1.38, 7.90), 9.34 (4.07, 21.44), 4.87 (2.08, 11.39) and 68.64 (17.29, 272.49), respectively, for patients with AMI and 1.93 (0.91, 4.12), 5.60 (1.60, 19.57), 3.51 (1.48, 8.33) and 38.57 (9.36, 158.94), respectively, for patients with unstable angina. Rates were similar between hospital types during the 22 months after discharge. The appropriateness of this large variation in resource use between metropolitan and non-metropolitan hospitals requires examination.

Objectives: To examine the benefits of a guideline-based educational program to improve management of unstable angina pectoris (UAP) in hospital patients. Design: Randomised controlled trial. Setting: 37 public hospitals across New South Wales. Patients: 1872 patients admitted with a diagnosis of UAP between 1 February and 30 June 1996 (baseline survey), and 1368 patients with the same diagnosis admitted between 1 July and 31 December 1998 (follow-up survey). Intervention: Educational sessions run by local opinion leaders, presenting guidelines on management of UAP from the National Health and Medical Research Council and feedback on local practice using data from the baseline survey. Sessions were run between March and June 1998. Main outcome measures: Use of evidence-based practice, identified by review of medical records. Results: Use of β-blockers increased in intervention and control hospitals, although the increase was significant only in the former. Use of calcium-channel blockers decreased significantly in both intervention and control hospitals. However, the change in drug use between baseline and follow-up did not differ significantly between intervention and control hospitals. Conclusions: Despite some appropriate changes in drug use for UAP management between 1996 and 1998, there was no evidence that a guideline-based educational program was of benefit in changing management. This reaffirms the difficulty of changing doctors' behaviour through practice guidelines. Alternative methods of encouraging evidence-based practice should be considered.