Screening for microalbuminuria to prevent nephropathy in patients with diabetes: a systematic review of the evidence.

OBJECTIVE: Our goal was to evaluate whether screening patients with diabetes for microalbuminuria (MA) is effective according to the criteria developed by Frame and Carlson and those of the US Preventive Services Task Force. STUDY DESIGN: We searched the MEDLINE database (1966-present) and bibliographies of relevant articles. OUTCOMES MEASURED: We evaluated the impact of MA screening using published criteria for periodic health screening tests. The effect of the correlation between repeated tests on the accuracy of a currently recommended testing strategy was analyzed. RESULTS: Quantitative tests have reported sensitivities from 56% to 100% and specificities from 81% to 98%. Semiquantitative tests for MA have reported sensitivities from 51% to 100% and specificities from 21% to 100%. First morning, morning, or random urine sampling appear feasible. Assuming an individual test sensitivity of 90%, a specificity of 90%, and a 10% prevalence of MA, the correlation between tests would have to be lower than 0.1 to achieve a positive predictive value for repeated testing of 75%. CONCLUSIONS: Screening for MA meets only 4 of 6 Frame and Carlson criteria for evaluating screening tests. The recommended strategies to overcome diagnostic uncertainty by using repeated testing are based on expert opinion, are difficult to follow in primary care settings, do not improve diagnostic accuracy sufficiently, and have not been tested in a controlled trial. Although not advocated by the American Diabetes Association, semiquantitative MA screening tests using random urine sampling have acceptable accuracy but may not be reliable in all settings.

Population-based time preferences for future health outcomes.

CONTEXT: Time preference (how preference for an outcome changes depending on when the outcome occurs) affects clinical decisions, but little is known about determinants of time preferences in clinical settings. OBJECTIVES: To determine whether information about mean population time preferences for specific health states can be easily assessed, whether mean time preferences are constant across different diseases, and whether under certain circumstances substantial fractions of the patient population make choices that are consistent with a negative time preference. DESIGN: Self-administered survey. SETTING: Family physician waiting rooms in four states. PATIENTS: A convenience sample of 169 adults. INTERVENTION: Subjects were presented five clinical vignettes. For each vignette the subject chose between interventions maximizing a present and a future health outcome. The options for individual vignettes varied among the patients so that a distribution of responses was obtained across the population of patients. MAIN OUTCOME MEASURE: Logistic regression was used to estimate the mean preference for each vignette, which was translated into an implicit discount rate for this group of patients. RESULTS: There were marked differences in time preferences for future health outcomes based on the five vignettes, ranging from a negative to a high positive (116%) discount rate. CONCLUSIONS: The study provides empirical evidence that time preferences for future health outcomes may vary substantially among disease conditions. This is likely because the vignettes evoked different rationales for time preferences. Time preference is a critical element in patient decision making and cost-effectiveness research, and more work is necessary to improve our understanding of patient preferences for future health outcomes.

The effect of labeling on perceived ability to recover from acute illnesses and injuries.

BACKGROUND: The process of giving a patient a diagnosis may cause harm. The adverse effects of labeling, best documented for the diagnosis of hypertension, include increased absenteeism from work and lower earnings, increased depressive symptoms, and reduced quality of life. We tried to determine whether the diagnosis of hypertension affects perceptions about the time required to recover from common acute medical problems. METHODS: In an academic family practice clinic, equal numbers of patients with and without hypertension were asked to estimate how long it would take them to recover from an upper respiratory tract infection (URI), a urinary tract infection (UTI), and an ankle sprain now and 5 years ago (before the diagnosis of hypertension). RESULTS: Compared with patients who did not have hypertension, patients with hypertension estimated that it would take them twice as long, on average, to recover from a URI now (11.7 vs 6.0 days, P=.002) and in the past (10 vs 5.5 days, P=.02). These differences persisted after controlling for age, sex, race, and education. No significant differences were found for estimated recovery times for UTI or ankle sprain. CONCLUSIONS: The diagnosis of hypertension may affect patients' perceptions of their ability to recover from unrelated acute illnesses. This may have implications for the way physicians choose to present information to patients.

Cost effectiveness of human immunodeficiency virus postexposure prophylaxis for healthcare workers.

OBJECTIVE: The United States Public Health Service (USPHS) published recommendations for human immunodeficiency virus (HIV) postexposure prophylaxis (PEP) of healthcare workers in May 1998. The aim of this study was to analyse the cost effectiveness of the USPHS PEP guidelines. DESIGN AND SETTING: This was a modelling study in the setting of the US healthcare system in 1989. The analysis was performed from the societal perspective; however, only HIV healthcare costs were considered and health-related losses of productivity were not included. METHODS: A decision tree incorporating a Markov model was created for 4 PEP strategies: the current USPHS recommendations, triple drug therapy, zidovudine monotherapy or no prophylaxis. A probabilistic sensitivity analysis using a Monte Carlo simulation was performed. Confidence intervals (CIs) around cost-effectiveness estimates were estimated by a bootstrapping method. RESULTS: The costs (in 1997 US dollars) per quality-adjusted life-year (QALY) save by each strategy were as follows: monotherapy $US688 (95% CI: $US624 to $US750); USPHS recommendations $US5211 (95% CI: $US5126 to $US5293); and triple drug therapy $US8827 (95% CI: $US8715 to $US8940). The marginal cost per year of life saved was: USPHS recommendations $US81 987 (95% CI: $US80 437 to $US83 689); triple drug therapy $US970 451 (95% CI: $US924 786 to $US 1 014 429). Sensitivity testing showed that estimates of the probability of seroconversion for each category of exposure were most influential, but did not change the order of strategies in the baseline analysis. With the prolonged HIV stage durations and increased costs associated with recent innovations in HIV therapy, the marginal cost effectiveness of the USPHS PEP strategy was decreased to $US62 497/QALY saved. All 3 intervention strategies were cost effective compared with no postexposure prophylaxis. CONCLUSIONS: Current USPHS PEP recommendations are marginally cost effective compared with monotherapy, but the additional efficacy of triple drug therapy for all risk categories is rewarded by only a small reduction in HIV infections at great expense. For the foreseeable future, assuming innovations in therapy that employ expensive drug combinations earlier in the HIV disease course to extend life expectancy and the increasing prevalence of HIV drug resistance, our model supports the use of the USPHS PEP guidelines.

Patient certification through mutual problem lists.

OBJECTIVE: To determine whether retired military personnel and spouses are cognizant of the patient's complete list of medical problems. METHODS: Receiving help from their spouses or other personal care givers, 12 patients listed their health problems from memory plus from a page-by-page review of their permanent medical records. The personal physician produced his own lists and combined them with the patient-generated lists. After mutual review, these combined lists were accepted as the mutual problem lists. Other professionals in the clinic also audited the same patients' charts. RESULTS: Twelve patients identified an average of 4.58 problems, the physician identified an average of 7.75 problems, and the other professionals identified an average of 6.54 problems. CONCLUSION: This lack of agreement has implications for patient education and certification as full collaborators in primary care.

A clinical decision analysis of cryotherapy compared with expectant management for cervical dysplasia.

BACKGROUND: Screening for precursors of cervical cancer with colposcopic examination for women with abnormal Papanicolaou (Pap) smears identifies those with cervical dysplasia. Though the majority of mild dysplasias (CIN I) will regress, many are treated with cryotherapy. METHODS: We used decision analysis to compare immediate cryotherapy with expectant management (following with another Pap smear or colposcopy, with treatment reserved for progression or a duration of 2 years). The decision tree included the possibility of more invasive surgical procedures if the cryotherapy was ineffective or if the dysplasia progressed in extent of cervical involvement or in grade. Probabilities were derived from literature review and expert judgment. The analysis considered the disutility of the follow-up examinations, cryotherapy, and the more invasive procedures, using expert assessment. RESULTS: Using the baseline assumptions, expectant management led to a better outcome for most patients (57%), who recover with no procedure. However, more patients treated with expectant management required surgical procedures (loop electrosurgical excisional procedure, conization, or, rarely, hysterectomy) than did those treated with immediate cryotherapy. In the expected disutility analysis, expectant management was better than immediate cryotherapy. Sensitivity analysis showed that three factors had the potential to change the recommendation of the analysis: (1) the probability the dysplasia will regress, (2) the disutility of the process of expectant management, and (3) the disutility of invasive procedures compared with cryotherapy. CONCLUSIONS: The analysis indicated that expectant management is preferable to immediate cryotherapy for women with histologically proven mild cervical dysplasia. However, this conclusion depended on assumptions about three factors for which there is insufficient evidence in the literature. More research is needed.

The accuracy of patients' judgments of disease probability and test sensitivity and specificity.

BACKGROUND: We studied patients' understanding of the characteristics of diagnostic tests for six common conditions to determine what patients know about diagnostic uncertainties before they communicate with a doctor. We compared the accuracy of patients' estimates of disease probabilities and diagnostic test characteristics for diseases with which they did or did not have prior experience. METHODS: To measure patients' understanding of the uncertainty of diagnostic test results, questionnaires describing diseases were given to patients in clinic waiting rooms. For each of six diseases, a 2-page questionnaire presented a case history of the disease and its diagnostic test, and asked respondents to estimate the probability that the case patient has the suspected disease, the sensitivity of test, the specificity of test, and the probability that the patient has the disease if the test result is positive. It also asked whether the patient, a close friend, or family member had ever been thought to have this disease. RESULTS: One hundred eighty-four patients in the clinic waiting room responded for at least one disease. Although patients judged the disease probabilities to be higher after a positive diagnostic test, each of their four judgments was essentially the same for all diseases, including those with high and low prior probabilities, and with accurate and inaccurate tests. Past experience with the disease was associated with only a minimal increase in the accuracy of patient knowledge. CONCLUSIONS: Patients' ignorance of the uncertainties of diseases demonstrates the need for patient education when a disease is suspected. The lack of relation between knowledge and experience suggests that this need is not being effectively met. To convey the rates or probabilities, and to help the patients understand what the probabilities are based on, a physician should speak in terms that patients can easily understand.

Beyond the black letter of the law: an empirical study of an individual judge's decision process for civil commitment hearings.

To study the role of parens patriae and "police powers" considerations in an individual judge's civil commitment decisions, the judge's reports of the impact of various characteristics of the patient were analyzed. The validity of this methodology was tested by comparing it to an alternative technique based on objective statistical analysis of the dependence of the judge's decisions upon patient characteristics. A probate court judge filled out a questionnaire after each civil commitment hearing over which he presided during a seven-month study. For each of 26 decisions, the judge rated the patient on 26 features and indicated the impact of each feature on the decision. The judge's responses were analyzed to measure the role of various statutory and nonstatutory considerations (expressed as patient characteristics) in the judge's decisions. Results using self-reported impacts are compared with an objective, statistical characterization of the judge's decision-making policy. As in previous studies, the parens patriae model more closely described the individual judge's decision process than the "police powers" model. Contextual variables (e.g., the patient's family favoring commitment) also were influential. Results with the two methods were similar. The methodology developed here can be used not only in further research on judicial commitment decisions but also to educate judges and other decision-makers individually faced with potentially tragic choices as to their personal implicit decision-making strategies.

Antibiotics and respiratory infections: do antibiotic prescriptions improve outcomes?

BACKGROUND AND OBJECTIVES: Antibiotics are frequently prescribed for respiratory infections though most of these infections are viral. To determine whether this practice contributes to patient health and patient satisfaction, we studied the effect of antibiotic prescriptions on outcomes at 7 to 10 days. We also studied the effect of antibiotic prescriptions upon the accuracy of patients' beliefs about viruses. METHODS: One hundred thirteen patients with a respiratory infection completed questionnaires before and after their visit with their primary care doctor. A phone interview was completed 7 to 10 days later. Questions elicited their expectations for antibiotics, their beliefs about the efficacy of antibiotics, and satisfaction with the doctor. The phone interview asked whether they felt better, whether they had returned to the doctor about the same illness, satisfaction, and whether they would expect antibiotics for the same disease in the future. The doctors provided information about their diagnosis and treatment. RESULTS: No correlation was found between prescription of antibiotics and patient satisfaction, feeling better, return physician visits, or phone calls. Receiving antibiotics increased the likelihood the patients would expect antibiotics the next time they had an upper respiratory infection and made them more likely to have an inaccurate belief, that antibiotics kill viruses. CONCLUSIONS: The study found no evidence that antibiotics improve patient outcome in upper respiratory infections by making patients feel better at 7 to 10 days. Nor did it find evidence that antibiotics help physicians by reducing return visits or increasing patient satisfaction. Doctors are invited to reconsider their policies for prescribing antibiotics for upper respiratory infection.

Antibiotics and respiratory infections: are patients more satisfied when expectations are met?

BACKGROUND: Antibiotics are frequently prescribed for respiratory infections, even though most of these infections are viral. To understand why physicians do so, we studied patients' and physicians' expectations for antibiotics and the effects of the patient-physician interaction on patient satisfaction. METHODS: Patients with a respiratory infection were asked to complete a questionnaire before and after visiting with physicians at three family medicine centers. Physicians completed a questionnaire following the visit. RESULTS: Sixty-five percent of the 113 patients with respiratory infection expected antibiotics. Physicians had some ability to perceive this expectation and frequently prescribed antibiotics for patients who expected them. Antibiotics were prescribed to over 75% of patients with sinusitis or bronchitis and to 18% of those diagnosed with only viral infections. No association was found between a prescription for antibiotics and patient satisfaction; however, patient satisfaction did correlate with the patients' report that they understood the illness and that the physician spent enough time with them. CONCLUSIONS: Physicians frequently prescribe antibiotics for upper respiratory infections when they believe patients expect it, but receiving a prescription for antibiotics is not in and of itself associated with increased patient satisfaction.

Clinical practice. How physicians make medical decisions and why medical decision making can help.

Medical decision making (MDM) contains tools that can contribute to the skill and expertise of physicians. MDM is especially useful for primary care physicians. Practicing in this clinical world is practicing in a world of great uncertainty--the world in which many of these tools were designed to be useful.

Physicians' expert cognition and the problem of cognitive biases.

This article reviews the ways in which physicians reason in order to account for medical mismanagement due to cognitive errors. Whether physicians make decisions intuitively or analytically, they may err due to the approximations of human reasoning. Vigilance, education, and programs at the level of the medical system are suggested as measures to make decisions consistent with the logic of decision analysis so that the effects of cognitive errors are minimized.

A glossary of medical decision-making terms.

Many of the terms used in medical decision making are foreign to clinicians. This problem creates a barrier that can prevent physicians from acquiring these new clinical tools. This glossary contains definitions of the most common terms as well as examples of their usage by using Down syndrome as the illustrative condition.

Prostate cancer screening. What family physicians believe is best.

OBJECTIVE: To determine current family physician beliefs concerning prostate cancer screening. DESIGN: Two hundred eighty-six Oklahoma family physicians were surveyed by mail. Fifty-three percent of physicians returned the questionnaire. Physicians were questioned on what tests they order for prostate screening, the reasons for ordering a serum prostate-specific antigen (PSA) test, what test results would cause a urologic referral for further evaluation of prostate cancer, and whether prostate cancer screening would decrease the patient's mortality or improve quality of life. RESULTS: Most physicians (74%) believed that both a digital rectal examination and a serum PSA determination are appropriate for prostate cancer screening. Physicians' primary reasons for ordering a PSA test were to decrease patient mortality and morbidity. Sixty-two percent of physicians believed that prostate cancer screening would decrease mortality and 69% agreed that screening would improve quality of life. Approximately 90% of physicians would refer patients with a PSA level greater than 12 micrograms/L or a PSA level of 5 micrograms/L and an indurated prostate. Significant variation was found between groups of physicians in their beliefs about prostate cancer screening. CONCLUSION: Although the literature has been inconclusive on the benefit of prostate cancer screening, the majority of Oklahoma family physicians would choose to screen their patients and believe that patients' mortality and morbidity are decreased by early identification of prostate cancer.

Thyroid disease in the elderly. Part 1. Prevalence of undiagnosed hypothyroidism.

BACKGROUND: The purpose of this study was to examine the prevalence of previously unrecognized hypothyroidism in elderly patients. METHODS: The study was conducted in a primary care geriatrics clinic. Three hundred seventy elderly patients (287 women, 83 men) between 60 and 97 years of age were included in the study. Medical records of patients were reviewed retrospectively. Serum thyroid-stimulating hormone (TSH), free thyroxine (T4), height, weight, demographic variables, clinical signs and symptoms of hypothyroidism, history of thyroid diseases and treatment with thyroid medications, comorbidities, and current medications were obtained from the medical records. Patients who had both elevated TSH levels (5.0 to 14.9 microU/mL) and normal free T4 levels (0.7 to 2.0 ng/dL) met the criteria for "subclinical hypothyroidism." The criteria for "overt hypothyroidism" were TSH levels > or = 15 microU/mL and low free T4 levels (< 0.7 ng/dL). RESULTS: At the initial visit to the clinic, 18.1% of the patients (62 female and 5 male) had an established history of past or current thyroid disease. Another 20 women (5.4%) had a history of thyroid surgery. Of the remaining 283 patients with no history of thyroid disease, 14.6% of the women and 15.4% of the men had subclinical hypothyroidism. Overt hypothyroidism was discovered and subsequently treated in two female patients and one male patient (1.0% and 1.3%, respectively). Thyroid status was not significantly related to age group (60 to 64 years; 65 to 74; 75 to 84; 85 and older). Comorbidities typically associated with hypothyroidism were no more prevalent in hypothyroid patients than in euthyroid patients. CONCLUSIONS: We found a high prevalence of newly diagnosed subclinical hypothyroidism in both elderly male and female patients. Thyroid status was not related to age or to coexisting diseases. The clinical significance of treating subclinical hypothyroidism merits investigation.