Lifting the veil off treatment effect heterogeneity.

Clinicians often suspect that a treatment effect can vary across individuals. However, they usually lack "evidence-based" guidance regarding potential heterogeneity of treatment effects (HTE). Potentially actionable HTE is rarely discovered in clinical trials and is widely believed (or rationalized) by researchers to be rare.

An Evaluation of a Telehealth Caregiver Training Package to Treat Food Selectivity.

Telehealth behavioral interventions are increasingly necessary when in-person services are not accessible (e.g., due to geographic location, time, cost, and health and safety restrictions).

The effects of antipsychotic medications on microbiome and weight gain in children and adolescents.

Background: Atypical antipsychotics, also known as second-generation antipsychotics, are commonly prescribed as treatment for psychotic disorders in adults, as well as in children and adolescents with behavioral problems. However, in many cases, second-generation antipsychotics have unwanted side effects, such as weight gain, potentially further increasing risk for morbidities including obesity, diabetes, and cardiovascular disease. While various mechanisms for this weight gain have been proposed, including effects on metabolic hormone signaling, recent evidence points to the importance of the gut microbiome in this process.

Dispositional Optimism and Cardiovascular Reactivity Accompanying Anger and Sadness in Young Adults.

Background: Dispositional optimism, a generalized expectation for positive outcomes, appears to promote physical health and well-being, including positive effects on cardiovascular disease outcomes. Mechanisms may involve adaptive responses to psychological stressors that dampen their physiological impact.

Purpose: This study investigated (i) whether individual differences in optimism are associated with attenuated cardiovascular reactivity (CVR); (ii) whether the CVR moderating effect of optimism differs for two stress emotions, anger and sadness; and (iii) whether separate measures of optimism and pessimism, and the more commonly used measure that combines them, differ in their relationships with CVR.

Post hoc subgroups in clinical trials: Anathema or analytics?

Background: There is currently much interest in generating more individualized estimates of treatment effects. However, traditional statistical methods are not well suited to this task. Post hoc subgroup analyses of clinical trials are fraught with methodological problems.

Expression level of the nm23 gene in clonal populations of metastatic murine and human neoplasms.

The purpose of this study was to determine whether nm23 steady-state mRNA expression levels correlate with metastatic potential of mouse K-1735 melanoma cells, human KM12 colon cancer cells, and human SN12 renal cancer cells. Since neoplasms are heterogeneous and contain subpopulations of cells with different metastatic potentials, we analyzed multiple sets of nonmetastatic and metastatic clones isolated from each neoplasm. In addition, we also examined nine somatic cell hybrids produced by the fusion of nonmetastatic and metastatic K-1735 clones.

International Federation of Clinical Chemistry (IFCC). Scientific Division. Committee on pH, Blood Gases and Electrolytes. Guidelines for transcutaneous pO2 and pCO2 measurement.

This document provides guidelines in the terminology, methodology, and in the interpretation of data obtained from the use of skin (transcutaneous) pO2 and pCO2 electrodes. The transcutaneous technique has found special application in newborn infants. The causes of analytical bias with respect to arterial blood gas values and imprecision obtained with transcutaneous pO2 and pCO2 electrodes are reviewed.

Guidelines for transcutaneous p O2 and p CO2 measurement.

This document provides guidelines in the terminology, methodology, and in the interpretation of data obtained from the use of skin (transcutaneous) p O2 and p CO2 electrodes. The transcutaneous technique has found special application for newborn infants. The causes of analytical bias with respect to arterial blood gas values and imprecision obtained with transcutaneous p O2 and p CO2 electrodes are reviewed.

International Federation of Clinical Chemistry (IFCC). Scientific Division. Committee on pH, Blood Gases and Electrolytes. Guidelines for transcutaneous PO2 and PCO2 measurement.

This document provides guidelines in the terminology, methodology, and in the interpretation of data obtained from the use of skin (transcutaneous) P02 and PCO2 electrodes. The transcutaneous technique has found special application in newborn infants. The causes of analytical bias with respect to arterial blood gas values and imprecision obtained with transcutaneous P02 and PCO2 electrodes are reviewed.

IFCC document stage 3, draft 1, dated 1989 02 01. An approved IFCC recommendation. IFCC method (1988) for tonometry of blood: reference materials for pCO2 and pO2. International Federation of Clinical Chemistry Scientific Division. Committee on pH, Blood Gases and Electrolytes.

A reference method for tonometry of blood is described. The document covers the theory of tonometry, the materials and equipment needed, and essential aspects of the tonometry procedure for blood. The partial pressures of oxygen and carbon dioxide in tonometered blood are accurately known and therefore this blood is recommended for assessing the accuracy of blood gas analyzers.

International Federation of Clinical Chemistry (IFCC), Scientific Division. Committee on pH. Blood Gases and Electrolytes. IFCC method (1988) for tonometry of blood: reference materials for pCO2 and pO2.

A reference method for tonometry of blood is described. The document covers the theory of tonometry, the materials and equipment needed, and essential aspects of the tonometry procedure for blood. The partial pressures of oxygen and carbon dioxide in tonometered blood are accurately known and therefore this blood is recommended for assessing the accuracy of blood gas analyzers.

International Federation of Clinical Chemistry (IFCC): Scientific Division, Committee on pH, Blood Gases and Electrolytes: Guidelines for Transcutaneouspo(2)andpco(2)Measurement.

This document provides guidelines for the terminology, methodology, and for the interpretation of data obtained from the use of skin (transcutaneous) po(2) and pco(2) electrodes. The transcutaneous technique has found special application in newborn infants. The causes of analytical bias with respect to arterial blood gas values, and imprecision obtained with transcutaneous pco(2) electrodes, are reviewed.

Ion-selective electrodes for sodium and potassium: a new problem of what is measured and what should be reported.

For clinical purposes the activities of Na+ and K+ obtained with ion-selective electrodes in undiluted whole blood or serum should be multiplied by an appropriate factor to obtain the same values as the substance concentrations obtained by flame photometry. The factor is primarily dependent on the mass concentration of water in normal plasma divided by the molal activity coefficient of Na+ (or K+) of normal plasma. We discuss the value of the molal activity coefficient of Na+ obtained by theoretical calculations and by direct measurement.

Pathogenesis of gallstones.

The three lipids in bile, cholesterol, lecithin, and bile salts (about 90 percent of the dry weight of normal gallbladder bile) are amphipathic substances having both hydrophobic and hydrophilic functional groups. Knowledge of the physicochemical factors of gallstone formation (especially cholesterol stones) has increased in the past two decades. The absolute amount of cholesterol supersaturation determines the extent of cholesterol precipitation.

Quality control of electrolyte analyzers. Evaluation of the anion gap average.

The authors have shown previously that averaging at least eight patient anion gaps provides a sensitive technic for the detection of systematic error in electrolyte analysis (Am J Clin Pathol 79:688-696, 1983). They conducted a retrospective and prospective evaluation of this technic on the ASTRA 4. One month of patient and control data were studied retrospectively and showed that 17/71 abnormally low patient anion gap averages were associated with violations in a multi-rule procedure, and 41/71 low averages were associated with violations in cusum, a more sensitive procedure.

Empirical Bayes estimation of individual growth-curve parameters and their relationship to covariates.

The analysis of growth curves has long been important in biostatistics. Work has focused on two problems: the estimation of individual curves based on many data points, and the estimation of the mean growth curve for a group of individuals. This paper extends a recent approach that seeks to combine data from a group of individuals in order to improve the estimates of individual growth parameters.

Evaluation of nutritional status.

The assessment of nutritional status has become very popular, especially for patients undergoing stress (surgery) or potential parenteral nutrition. Evaluation of cancer patients is essentially the same as for other patients. Body fat reserves are approximated by subcutaneous skinfold measurements.