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Doctors' Offices (doctor + office)
Selected AbstractsHighly selective artificial gel antibodies for detection and quantification of biomarkers in clinical samples.JOURNAL OF SEPARATION SCIENCE, JSS, Issue 22 2008Abstract High selectivity of a biomarker is a basic requirement when it is used for diagnosis, prognosis and treatment of a disease. The artificial gel antibodies, which we synthesise by a molecular imprinting method, have this property not only for proteins, but also for bioparticles, such as viruses and bacteria. However, diagnosis of a disease requires not only that the biomarker can be "fished out" from a body fluid with high selectivity, but also that its concentration in the sample can rapidly be determined and preferably by a simple technique. This paper deals primarily with the development of a spectrophotometric method, which is so simple and fast that it can be used with advantage in a Doctor's Office. The development of this method was not straight-forward. However, by modifications of the performance of these measurements we can now design standard curves in the form of a straight line, when we plot the true (not the recorded "apparent" absorption) against known protein concentrations. In an additional publication (see the following paper in this issue of JSS) we show an application of such a plot: determination of the concentration of albumin in serum and cerebrospinal fluid from patients with neurological disorders to investigate whether albumin is a biomarker for these diseases. [source] Selection correction and sensitivity analysis for ordered treatment effect on count responseJOURNAL OF APPLIED ECONOMETRICS, Issue 3 2004Myoung-Jae Lee In estimating the effect of an ordered treatment , on a count response y with an observational data where , is self-selected (not randomized), observed variables x and unobserved variables , can be unbalanced across the control group (, = 0) and the treatment groups (, = 1, ,, J). While the imbalance in x causes ,overt bias' which can be removed by controlling for x, the imbalance in , causes ,covert (hidden or selection) bias' which cannot be easily removed. This paper makes three contributions. First, a proper counter-factual causal framework for ordered treatment effect on count response is set up. Second, with no plausible instrument available for ,, a selection correction approach is proposed for the hidden bias. Third, a nonparametric sensitivity analysis is proposed where the treatment effect is nonparametrically estimated under no hidden bias first, and then a sensitivity analysis is conducted to see how sensitive the nonparametric estimate is to the assumption of no hidden bias. The analytic framework is applied to data from the Health and Retirement Study: the treatment is ordered exercise levels in five categories and the response is doctor office visits per year. The selection correction approach yields very large effects, which are however ruled out by the nonparametric sensitivity analysis. This finding suggests a good deal of caution in using selection correction approaches. Copyright © 2004 John Wiley & Sons, Ltd. [source] Reliability and Validity of the Alcohol Use Disorders Identification Test (AUDIT) Imbedded Within a General Health Risk Screening Questionnaire: Results of a Survey in 332 Primary Care PatientsALCOHOLISM, Issue 5 2000Jean-Bernard Daeppen Background: Self-administered, general health risk screening questionnaires that are administered while patients wait in the doctor's office may be a reasonable and timesaving approach to address the requirements of preventive medicine in a typical 10-min medical visit. The psychometric characteristics of the Alcohol Use Disorders Identification Test (AUDIT) incorporated within a health questionnaire (H-AUDIT) have not been examined. Methods: The reliability and validity of the self-administered AUDIT were compared between the H-AUDIT and the AUDIT used as a single scale (S-AUDIT) in 332 primary care patients. Results: No major demographic or alcohol use characteristics were found between the 166 subjects who completed the H-AUDIT and the 166 individuals who completed the S-AUDIT. The test-retest reliability of the 166 subjects who completed the H-AUDIT [estimated by Spearman correlation coefficient at a 6-week interval (0.88), internal consistency (total correlation coefficients for all items ranged from 0.38 to 0.69; Cronbach , index 0.85), and the sensitivity and specificity of the H-AUDIT were used to identify at-risk drinkers' areas under receiver operating characteristic (0.77) and alcohol-dependent subjects' areas under receiver operating characteristic (0.89)] was similar to the same measurements obtained with the 166 individuals who completed the S-AUDIT. Conclusions: The AUDIT incorporated in a health risk screening questionnaire is a reliable and valid self-administered instrument to identify at-risk drinkers and alcohol-dependent individuals in primary care settings. [source] Why do primary care doctors diagnose depression when diagnostic criteria are not met?INTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 3 2000Michael Höfler Abstract This study examines predictors of false positive depression diagnoses by primary care doctors in a sample of primary care attendees, taking the patients' diagnostic status from a self-report measure (Depression Screening Questionnaire, DSQ) as a yardstick against which to measure doctors' correct and false positive recognition rates. In a nationwide study, primary care patients aged 15,99 in 633 doctors' offices completed a self-report packet that included the DSQ, a questionnaire that assesses depression symptoms on a three-point scale to provide diagnoses of depression according to the criteria of DSM-IV and ICD-10. Doctors completed an evaluation form for each patient seen, reporting the patient's depression status, clinical severity, and treatment choices. Predictor analyses are based on 16,909 patient-doctor records. Covariates examined included depression symptoms, the total DSQ score, number and persistence of depression items endorsed, patient's prior treatment, history of depression, age and gender. According to the DSQ, 11.3% of patients received a diagnosis of ICD-10 depression, 58.9% of which were correctly identified by the doctor as definite threshold, and 26.2% as definite subthreshold cases. However, an additional 11.7% of patients not meeting the minimum DSQ threshold were rated by their doctors as definitely having depression (the false positive rate). Specific DSQ depression items endorsed, a higher DSQ total score, more two-week depression symptoms endorsed, female gender, higher age, and patient's prior treatment were all associated with an elevated rate of false positive diagnoses. The probability of false positive diagnoses was shown to be affected more by doctors ignoring the ,duration of symptoms' criterion than by doctors not following the ,number of symptoms' criterion for an ICD or DSM diagnosis of depression. A model selection procedure revealed that it is sufficient to regress the ,false positive diagnoses' on the DSQ-total score, symptoms of depressed mood, loss of interest, and suicidal ideation; higher age; and patient's prior treatment. Further, the total DSQ score was less important in prediction if there was a prior treatment. The predictive value of this model was quite good, with area under the ROC-curve = 0.86. When primary care doctors use depression screening instruments they are oversensitive to the diagnosis of depression. This is due to not strictly obeying the two weeks duration required by the diagnostic criteria of ICD-10 and DSM-IV. False positive rates are further increased in particular by the doctor's knowledge of a patient's prior treatment history as well as the presence of a few specific depression symptoms. Copyright © 2000 Whurr Publishers Ltd. [source] Ineffectiveness of sun awareness posters in dermatology clinicsJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 6 2010GW Jung Abstract Background, Although sun awareness posters have been used in doctors' offices and clinics for decades to promote sun protective behaviour, there is no evidence of their usefulness. Objectives, To investigate whether sun awareness posters lead to inquiry of skin cancer and sun protection measures. Method, Patients considered at risk for skin cancer seen at a dermatology clinic were randomly asked to complete a questionnaire designed to assess the effectiveness of three different sun awareness posters placed in patient rooms. The posters were selected on the basis of their catchy slogan and eye-appealing images, and included those featuring parental interest, sex appeal and informative advice. Results, Only half of the patients noticed the posters (50.6%). The poster with sex appeal garnered the most attention (67.8%), followed by the informative poster (49.2%) and the parental interest poster (35.8%) (P < 0.001). Although patients who noticed the sun awareness poster inquired about cutaneous cancers and sun protection practices twice as often as those who did not notice the poster, only one-tenth of such inquiries were attributed to the poster (,5% of the target population). As reported in the questionnaire, the posters themselves were less effective than the advice of physicians in influencing patient attitudes towards sun protection measures. Conclusion, Organizations that produce and disseminate posters should consider beyond focus groups when they design their posters and should consider field testing their products to ensure that they are reaching the targeted audience and are having the expected beneficial effect, otherwise their posters are simply decorative. [source] | ||||||||||