Effects of simplifying choice tasks on estimates of taste heterogeneity in stated-choice surveys

Researchers usually employ orthogonal arrays or D-optimal designs with little or no attribute overlap in stated-choice surveys. The challenge is to balance statistical efficiency and respondent burden to minimize the overall error in the survey responses. This study examined whether simplifying the choice task, by using a design with more overlap, provides advantages over standard minimum-overlap methods. We administered two designs for eliciting HIV test preferences to split samples. Surveys were undertaken at four HIV testing locations in San Francisco, California. Personal characteristics had different effects on willingness to pay for the two treatments, and gains in statistical efficiency in the minimal-overlap version more than compensated for possible imprecision from increased measurement error.     

Pain and faulty breathing: a pilot study

The purpose of this pilot study was to observe both relaxed and deep breathing patterns in a convenience sample to determine the incidence of normal versus faulty patterns of respiration. These observations were then combined with respondent answers to a survey on pain history to determine if there is any correlation between faulty breathing and musculo-skeletal pain patterns. If such a correlation can be made, then we propose that clinicians working with chronic pain patients may have improved outcomes if they address and correct faulty breathing patterns. Based on this study, it is suggested to include the evaluation and treatment of faulty respiration in the rehabilitation of chronic musculo-skeletal conditions, most notably cervical pain.     

Reduced blood clearance and increased urinary excretion of N-nitrosodimethylamine in patas monkeys exposed to ethanol or isopropyl alcohol.

Low concentrations of N-nitrosodimethylamine are metabolized in rodent and human liver by cytochrome P450IIE1, an activity competitively inhibitable by ethanol. In rodents coadministration of ethanol with N-nitrosodimethylamine results in increased tumorigenicity in extrahepatic organs, probably as a result of reduced hepatic clearance. To test this concept in a primate, the effects of ethanol cotreatment on the pharmacokinetics of N-nitrosodimethylamine were measured in male patas monkeys. Ethanol, 1.2 g/kg given p.o. before i.v. N-nitrosodimethylamine (1 mg/kg) or concurrently with an intragastric dose resulted in a 10-50-fold increase in the area under the blood concentration versus time curves and a 4-13-fold increase in mean residence times for N-nitrosodimethylamine. Isopropyl alcohol, 3.2 g/kg 24 h before N-nitrosodimethylamine, also increased these parameters 7-10-fold; this effect was associated with persistence of isopropyl alcohol and its metabolic product acetone, both IIE1 inhibitors, in the blood. While no N-nitrosodimethylamine was detected in expired air, trace amounts were found in urine. Ethanol and isopropyl alcohol pretreatment increased the maximum urinary N-nitrosodimethylamine concentration 15-50-fold and the percentage of the dose excreted in the urine by 100-800-fold. Thus ethanol and isopropyl alcohol greatly increase systemic exposure of extrahepatic organs to N-nitrosodimethylamine in a primate.     

Leukocyte count and risk of major coronary heart disease events.

The association between leukocyte count and subsequent risk of major coronary heart disease events was examined using data from three prospective cohort studies--two from the United States and one from Great Britain. A total of 28,181 middle-aged men were followed for 6-12 years. A total of 1,768 men had a nonfatal myocardial infarction or died of coronary heart disease. In all three cohorts, there was a positive, statistically significant relation between baseline leukocyte count and risk of subsequent major coronary heart disease events after adjustment for age, serum total cholesterol, diastolic blood pressure, and number of cigarettes smoked per day (relative odds = 1.32 (p less than 0.0001), 1.15 (p = 0.0001), and 1.14 (p = 0.003), corresponding to a 2,000/mm3 difference in leukocyte count). The associations persisted when all nonsmokers (former smokers plus never smokers) and never smokers alone were considered and when those with evidence of preexisting coronary heart disease at baseline were excluded. Leukocyte count appears to be an indicator of a person's future risk of major coronary heart disease events.     

The role of infectious agents in the spondylarthropathies

The clinical similarities of the spondylarthropathies and their frequent association with both HLA B27 and microbial infections suggest common pathogenetic mechanisms. The latter may include deposition of immune complexes containing bacterial antigens. or cross-reactivity of such antigens with host target tissue or responding cell antigens. Enteric bacteria, chlamydia and mycoplasma are all candidate etiologic agents, but proof is difficult because they are often found as normal flora, although only genetically susceptible individuals may acquire disease, and many patients have been treated with antibiotics before they can be studied. Nonetheless, a role for endogenous bacteria in reactive arthritis at least seems certain, and should stimulate further investigation into similar pathogenetic mechanisms in other chronic arthritides.     

PRIMARY CARE FOR WOMEN: Comprehensive Assessment of the Head and Neck

This article reviews the pertinent anatomy of each body system involved in the assessment of the head and neck (including the eyes, ears, nose, and throat) and describes the basic elements of the comprehensive health assessment. Frequently encountered chief complaints are discussed. Aspects of the health assessment that will assist the primary care provider in making a differential diagnosis and determining the need for referral are presented. This article is the first of two articles on this topic; the subsequent article will address primary care management of common conditions of the head and neck.