Appraising published claims about drug treatment to implement best therapy in clinical practice

The validity and applicability of publications about individual clinical studies and systematic overviews regarding interventions with drugs need to be established and perceived in quantitative terms to implement evidence-based, best current therapy. This requires an understanding of study design, various types of bias, intention to treat analysis, clinical versus statistical significance, and other considerations. The quantitative appreciation of drug effects may be facilitated by arranging results from case-control studies, cohort studies, and controlled trials in suitable contingency tables. Relative risks, relative risk reductions, odds ratios, and absolute risk reductions (in a given period of time), as well as corresponding numbers needing treatment (to prevent one event) may then be calculated. Systematic overviews of multiple clinical trials and assessment of their combined quantitative significance (meta-analyses) were developed to enhance statistical power, to enhance the level of confidence about small differences in effect, and to reconcile conflicting claims. The results of a meta-analysis are usually represented by so-called 'forest plots' of point estimates (corresponding to medians) and their respective confidence intervals, as well as a combined point estimate and confidence interval. Heterogeneity (important differences between findings from individual trials is a special problem incurred with this relatively new tool. The meta-analysis are also specially prone to other special sources of bias' a greater likelihood that trials reporting 'favourable' effects are published, covert duplicate inclusion of results from the same patients, and non-blinded meta-analyserspublished_or_final_versio

Impact of chronic diseases on health services and quality of life of a Chinese population

Abstract Background: Chronic diseases are becoming the major global burden of disease. Information on their impact on health services and quality of life of individual patients can facilitate the provision of appropriate care. Objectives: To determine the self reported prevalence of chronic diseases and their impact on health service utilization and quality of life of individual patients. Methods: A cross sectional random telephone survey was conducted on 2410 Chinese adults from the general population in Hong Kong using both a structured questionnaire and the 36 item short form Health Survey (SF-36). The effects of chronic diseases on consultation rates, hospitalization risk and the SF-36 scores were analyzed by multivariate stepwise regressions, controlling for sociodemographic variables and comorbidity. Results: A total of 38% of subjects reported one or more chronic diseases with 59% being less than 60 years. Chronic joint problems were the most common. Every additional chronic disease increased the annual number of consultations by 60% and the likelihood of hospitalization in the last year by 79%. Most chronic diseases had a negative impact on quality of life with most associated with psychological problems. Conclusions: One in three Chinese adults in Hong Kong reported having chronic diseases. The total number of chronic diseases had a linear relationship with service utilization, which could be a useful medical risk adjustment factor. Enhancing quality of life should be an important aim in the management of chronic diseases.postprin

Is a desk-top analyzer the answer to cholesterol screening?

This is the first evaluation study on the acceptability and accuracy of the Reflotron, a desktop analyzer for cholesterol screening in general practice in Hong Kong. Patients aged 21-60 attending a Government general outpatient clinic in Hong Kong were randomly selected. The acceptance rate of screening was 69%. A total of 1113 subjects had their cholesterol levels screened by the Reflotron. The accuracy of the Reflotron was assessed by comparing its results to laboratory blood cholesterol (BC) results in 125 subjects. The mean error of the Reflotron cholesterol measurements was 6% which was larger than that recommended by the American National Cholesterol Education Programme. Therefore, the diagnosis or treatment of hypercholesterolaemia should not be based on the Reflotron result alone. There was a good linear correlation between the Reflotron cholesterol (RC) and blood cholesterol (BC) with a negative bias in the Reflotron results. Blood cholesterol could be predicted from RC by the regression equation: BC = 0.8395 + 0.8995 x RC. The Reflotron is useful as an initial screening test for hypercholesterolaemia in the low risk population. The threshold levels need to be adjusted accordingly, and abnormal results should be confirmed by standard laboratory tests. It is estimated that one could save H.K.$51.6 million if the Reflotron instead of the laboratory were used to screen all people aged 40 to 60 years old in Hong Kong once.published_or_final_versio

Appropriate use of clopidogrel

Editorialpublished_or_final_versio

What type of primary care services does the public want?

Objective: To find out what type of primary care services the public in Hong Kong wants. Design: Cross sectional population telephone survey. Subjects: 996 Cantonese speaking Chinese adults aged 21 years or above were randomly selected from households in Hong Kong. Main outcome measures: People's preference for the type of practices, doctors, access systems, consultations and other services in primary care. Results: Most people preferred to consult the same doctor close to their homes. Many people wanted doctors to be available in the evenings, weekends and public holidays. More people preferred a walk-in than a telephone appointment system. Most thought it was important for their primary care doctors to have higher medical qualifications. More people preferred male to female doctors. The majority (68%) thought an average consultation should last for more than 5 minutes. Over 90% thought it was important for the doctor to give detailed explanations on their illnesses and treatments. Many wanted primary care practices to provide preventive care. Thirty-seven percent of subjects would consult specialists without referrals. Thirty percent of people agreed that nurses could be responsible for following up chronic diseases but only 16% thought they could treat minor illnesses. Conclusion: The study confirmed that the public wanted accessible, available and comprehensive primary care services provided by doctors with postgraduate higher medical qualifications. Contrary to previous beliefs, most people preferred to consult the same doctor all the time and people wanted explanation as much as medications from doctors.published_or_final_versio

The heart protection study findings with simvastatin reanalysed by number needed to treat

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Anti-asthmatic drug usage and mortality trends in Hong Kong

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Population based norming of the Chinese (HK) version of the SF-36 health survey

Objective: The aim of this study was to establish normative values of the SF-36 Health Survey of the Chinese adult population in Hong Kong so that local references for meaningful interpretation of health-related quality of life (HRQOL) measurements would be available. Design: A cross-sectional telephone survey. Subject: Chinese adults aged 18 years or above randomly selected from the general population in Hong Kong. Main outcome measures: The Chinese (HK) SF-36 Health survey and demographic variables. The normative values of the SF-36 of the general population and different age/sex groups. Results: 2410 subjects completed the survey. The SF-36 scores on Physical Functioning, Role-physical, Bodily Pain and Social Functioning of the study sample were higher but the scores on General Health, Role-emotional and Mental Health were lower than those of the US norms. Age and gender had significant and substantial effects on the SF-36 scores. There was a social class gradient on the General Health, Vitality and Mental Health scores. Other demographic factors had little or no effects on the SF-36 scores. Conclusion: The Chinese (HK) version of the SF-36 is, at present, the only HRQOL measure that has been both validated and normed on Chinese adults in Hong Kong. It can be used as a standard HRQOL instrument to measure the impact of illnesses and the effect of interventions on the quality of life of our Chinese population.published_or_final_versio

Detection of body temperature with infrared thermography: accuracy in detection of fever

Key Messages 1. Infrared thermography (IRT) for detecting body temperature is less accurate in women, elderly people, and those with fever. 2. The core temperature significantly but weakly correlates to the IRT temperatures obtained from frontal and lateral of the face, and the forehead. 3. Among the three areas, the forehead IRT temperature showed the largest discrepancy and poorest correlation with the core temperature. 4. If IRT is used, the lateral maximum temperature of the face should be used. A cut-off temperature of 36ºC gives 77% sensitivity and 74% specificity. 5. Owing to its weak correlation with the core temperature, IRT should not replace direct body temperature measurement in clinical situations.published_or_final_versio

The effect of health-related quality of life (HRQOL) on health service utilisation of a Chinese population

This study was designed to find out whether health-related quality of life (HRQOL) was an independent determinant of health service utilisation of a Chinese population and to determine whether the addition of HRQOL data to sociodemographic and morbidity factors could significantly increase the explanatory power of risk-adjustment models. A cross-sectional random telephone survey of the general adult Chinese population in Hong Kong was conducted among 2410 Chinese aged 18-88yr old, 52% were females and 38% had one or more chronic diseases. Health service utilisation was measured by annual consultation, monthly consultation and hospitalisation rates. HRQOL was measured by the SF-36. Multivariate regressions were used to test the dependence of service utilisation rates on sociodemographic factors, chronic morbidity and the SF-36 scores. Structured multiphase regression analyses were used to determine the magnitude of the effect of the SF-36 scores, in addition to those of sociodemographic and chronic morbidity factors, on service utilisation. Five of eight SF-36 scores were independent determinants of consultation rates. They doubled and tripled the percentages of variance explained for annual and monthly consultation rates, respectively. Role limitation by physical problems and bodily pain scores had a significant effect on hospitalisation rates. This was the first study showing a linear relationship between HRQOL and service utilisation on a Chinese population. It confirmed the clinical relevance of the SF-36 to a culture and health care system that is different from that of the United States where the instrument originated. © 2002 Elsevier Science Ltd. All rights reserved.postprin