Pre-referral rectal artesunate in severe malaria: flawed trial.

Background: Immediate injectable treatment is essential for severe malaria. Otherwise, the afflicted risk lifelong impairment or death. In rural areas of Africa and Asia, appropriate care is often miles away.

Calculating unreported confidence intervals for paired data.

Background: Confidence intervals (or associated standard errors) facilitate assessment of the practical importance of the findings of a health study, and their incorporation into a meta-analysis. For paired design studies, these items are often not reported. Since the descriptive statistics for such studies are usually presented in the same way as for unpaired designs, direct computation of the standard error is not possible without additional information.

Outcome based subgroup analysis: a neglected concern.

Background: A subgroup of clinical trial subjects identified by baseline characteristics is a proper subgroup while a subgroup determined by post randomization events or measures is an improper subgroup. Both types of subgroups are often analyzed in clinical trial papers. Yet, the extensive scrutiny of subgroup analyses has almost exclusively attended to the former.

No short-cut in assessing trial quality: a case study.

Background: Assessing the quality of included trials is a central part of a systematic review. Many check-list type of instruments for doing this exist. Using a trial of antibiotic treatment for acute otitis media, Burke et al.

Simple polynomial multiplication algorithms for exact conditional tests of linearity in a logistic model.

The linear logistic model is often employed in the analysis of binary response data. The well-known asymptotic chi-square and likelihood ratio tests are usually used to detect the assumption of linearity in such a model. For small, sparse, or skewed data, the asymptotic theory is however dubious and exact conditional chi-square and likelihood ratio tests may provide reliable alternatives.

Quality of life in the first year after breast cancer surgery: rehabilitation needs and patterns of recovery.

Background: Although mortality rates from breast cancer are declining, many breast cancer survivors will experience physical and psychological sequelae that affect their everyday lives. Few prospective studies have examined the rehabilitation needs of newly diagnosed breast cancer patients, and little is known about the predictors of health-related quality of life (QOL) in this population.

Methods: Between 1987 and 1990, 227 women with early stage breast cancer participated in a prospective longitudinal study in which detailed information was collected through interviews, standardized measures of QOL and psychological distress, and clinical evaluation.

Exact and asymptotic tests for homogeneity in several 2 x 2 tables.

This paper presents the results of a Monte Carlo study comparing the performance, in terms of size and power, of six exact and six asymptotic tests for the homogeneity of odds ratios in several 2 x 2 contingency tables. With a small sample size or sparse data structure, the exact tests performed better than the asymptotic tests because they maintained the nominal size and, in some situations, had slightly higher power. Among the exact tests, we recommend the Zelen, Pearson chi-square and scores tests.

Major expansions of select CD8+ subsets in acute Epstein-Barr virus infection: comparison with chronic human immunodeficiency virus disease.

CD8+ lymphocyte phenotypes were characterized during acute Epstein-Barr virus (EBV) infection, and a comparison was made to previous studies of human immunodeficiency virus (HIV). This was of interest because CD8+ cells contribute to immunologic control of both infections, but the usual outcome of EBV infection is benign, whereas untreated HIV infection is fatal. During acute EBV infection, CD8+ cells expressed elevated levels of the activation antigens CD38 and HLA-DR, similar to that during chronic HIV infection.

Shortened telomeres in the expanded CD28-CD8+ cell subset in HIV disease implicate replicative senescence in HIV pathogenesis.

Objective: To test the hypothesis that the expanded population of non-proliferative CD28-CD8+ T cells in HIV disease have shortened telomeres, thereby providing evidence that increased rounds of CD8+ cell division occur during HIV disease, possibly leading to replicative senescence and exhaustion of CD8+ T-cell responses.

Design: CD8+ cells play a central role in control of HIV infection. In late HIV disease, an expanded population of CD28-CD8+ cells with reduced proliferative potential has been documented.

Persistently seronegative men from whom HIV-1 has been isolated are genetically and immunologically distinct.

Studies in both monkeys and humans have suggested that transient infection with HIV-1 can occur without provoking a measurable humoral immune response. The objective of this study was to look for genetic and immunologic correlates of transient HIV-1 infection in antibody-negative men from whom HIV-1 had been isolated. The distributions of MHC class I, class II, and TAP (transporter protein associated with antigen processing) region genes were compared between 23 persistently seronegative men from whom HIV-1 was isolated at least once (isol+/Ab-) and 137 men who seroconverted.

Natural killer cell immunodeficiency in HIV disease is manifest by profoundly decreased numbers of CD16+CD56+ cells and expansion of a population of CD16dimCD56- cells with low lytic activity.

Natural killer (NK) cells were enumerated by three-color immunofluorescence in 255 uninfected and 399 human immunodeficiency virus-infected adults. Several dramatic alterations were observed. First, the median number and percentage of CD16+CD56+ NK cells, the subset that comprises > 90% of the NK cells in healthy adults, were severely decreased (median, 175/mm3 in uninfected controls; 63/mm3 in HIV-infected non-AIDS subjects).

Exact power computation for dose-response studies.

The toxicity of an agent or the therapeutic effect of a drug may be assessed by a dose-response study. We present a method for computing the exact power of exact and large sample statistical tests employed for binary response data from such a study. This method, based on recursive polynomial multiplications, enables fast computation of exact power for studies with up to a moderately large sample size.

Effects of a program to train radiologic technologists to identify abnormalities on mammograms.

Purpose: To assess whether radiologic technologists could be successfully trained to identify abnormalities on mammograms.

Materials And Methods: Eight radiologic technologists from two different institutions took a pretest, underwent an 8-hour training course followed by a period of preceptorship, and then took a posttest. Seven radiologists also took the pretest and posttest, which consisted of evaluating 1,238 two-view screening examinations, including 318 biopsy-proved cancers.

Exact analysis for paired binary data.

This paper provides an efficient algorithm to generate exact distributions for the bivariate logistic model with common and sub-unit-specific covariates. The algorithm can be used to analyze correlated paired binary response data from studies lacking a large sample size. Possible applications include a clinical trial with two distinct binary outcomes, a binary outcome cross-over or two-time point cohort study, and a pair-matched prospective study with binary outcome.

CD8+ lymphocyte activation at human immunodeficiency virus type 1 seroconversion: development of HLA-DR+ CD38- CD8+ cells is associated with subsequent stable CD4+ cell levels. The Multicenter AIDS Cohort Study Group.

Subsets of activated CD8+ lymphocytes defined by membrane expression of the activation antigens HLA-DR and CD38 were counted by three-color flow cytometry in homosexual men who subsequently became seropositive for human immunodeficiency virus type 1 (HIV). Profound CD8+ cell activation was seen in all subjects at seroconversion and 6 and 12 months later. The HLA-DR+ CD38+ CD8+ cell population, which has potent direct HIV cytotoxic T cell activity, was markedly elevated at seroconversion in all subjects.

Efficient power computation for exact and mid-P tests for the common odds ratio in several 2 x 2 tables.

When designing a study that may generate a set of sparse 2 x 2 tables, or when confronted with 'negative' results upon exact analysis of such tables, we need to compute the power of exact tests. In this paper we provide an efficient approach for computing exact unconditional power for four exact tests on the common odds ratio in a series of 2 x 2 tables. These tests are the traditional exact test; a test based on a probability ordering of the sample space; and two tests based on ordering the sample space according to distance from the mean, or median.

An assessment of the use of anthropometric measures for predicting low birth weight.

We report results of an evaluation of two anthropometric surrogates, viz chest circumference and mid-arm circumference, of birth weight. Optimal criteria for predicting birth weight below 2000 g and below 2500 g were provided by use of chest circumference alone. However, even the best criterion was not very sensitive indicating that use of anthropometric surrogates may have a limited practical value.

Predicting psychosocial risk in patients with breast cancer.

Breast cancer is the most common neoplasm in North American women. The psychosocial impact of breast cancer has been extensively studied, and a number of investigators have attempted to characterize women who are at high risk for increased psychosocial morbidity. Although a detailed interview performed by a professional is the clinical standard for psychosocial assessment, such interviews are usually time-consuming and expensive, and thus are rarely performed.

Characteristics of women at risk for psychosocial distress in the year after breast cancer.

Purpose: To provide a detailed description of rehabilitation problems of women, considered to be low risk and at risk for psychosocial morbidity, diagnosed with stage I and II breast cancer 1 month and 1 year after primary treatment.

Patients And Methods: A sample of 227 newly diagnosed breast cancer patients were systematically interviewed by a clinical social worker and classified for risk of psychosocial distress in the year after diagnosis. They completed a battery of standardized instruments to assess quality of life (QL), rehabilitation needs, and psychologic distress.

Describing the health-related quality of life impact of HIV infection: findings from a study using the HIV Overview of Problems--Evaluation System (HOPES).

This study aimed to describe the results of findings from data collected with an HIV-specific health-related quality of life tool, and to examine the relationship between clinical and biological factors and health-related quality of life (HRQL). Data were collected as a cross-sectional, patient-completed assessment of health-related quality of life. Laboratory data were abstracted from the medical chart.

Nosocomial bacterial infections among children with severe protein energy malnutrition.

The incidence of hospital acquired acute bacterial infections among 164 severely malnourished children admitted to the paediatric wards at the Muhimbili Medical Centre in Dar es Salaam were studied. On admission, ninety two per cent of the patients had at least one form of bacterial infection. During the subsequent two weeks hospital stay, 49% of the patients acquired a new infection.

Carcinoma of the male breast in Tanzania.

This is a retrospective study of male mammary carcinoma in Tanzania based on biopsy material received from 1974 to 1987 at the Tanzania Cancer Registry. In a series of 1104 cases of breast cancer, 76 or 6.5% were male.