A collection of 56 topics with contradictory results in case-control research.

This research was done to learn more about the frequency and characteristics of conflicting research in case-control studies. In a survey of the epidemiological and medical literature, we found 56 topics in which the results of a case-control study were in conflict with the results from other studies of the same relationship. Cancer was the associated disease for 30 of the controversial topics.

How to evaluate a diagnostic marker test. Lessons from the rise and fall of dexamethasone suppression test.

To understand why the dexamethasone suppression test (DST) for the diagnosis of depression became widely accepted and later rejected, we reviewed the sequence of publications in the DST literature. To evaluate the events, we developed and applied concepts of a five-phase process that can be used to assess the clinical utility of diagnostic marker tests. The review showed that when the DST was introduced into the clinical arena, the initial and final two phases of testing (I, IV, and V) had not been adequately conducted.

A box-graph method for illustrating relative-size relationships in a 2 x 2 table.

The proportional relationships of the four numbers in a 2 x 2 table can be displayed using two types of box graphs. In one approach, a 'unitary square' is first divided according to the denominator proportions of the two groups formed in a cohort or case-control study, and then re-divided according to the numerator proportions in each group. In the second method, the numbers are arranged as four squares, proportionately sized according to the square root of each number, and contiguously adjacent to a central reference point.

A review of systems for the personal aspects of patient care.

Because patients are appropriate judges of the personal aspects of the care received from physicians, the authors conducted lengthy interviews with 50 randomly chosen medical inpatients. They were asked to describe, in an open-ended but semistructured fashion, their favorable and unfavorable impressions and reactions to the personal aspects of care rendered by their physicians. From the specific comments made by the patients in these interviews, we constructed a detailed taxonomy of desired physician attitudes and behaviors.

The value and hazards of standardization in clinical epidemiologic research.

The statistical standardization of rates produces a single summary value that converts crude rates of occurrence into "standardized" rates that are adjusted for differences in the composition of compared populations. Although the process is well described in the epidemiologic literature and is regularly applied in comparisons of large populations, many investigators are not familiar with three important hazards that are magnified for the smaller groups studied in clinical epidemiologic research. This report contains a new "symmetrical" outline of the direct and indirect standardization processes, and an illustration of three pragmatic hazards: (1) Because the direct standardizing factor uses the observed stratum-specific rates, and because any stratum-specific rates that depend on small denominators may be misleading or unstable, the indirect method is preferred when the observed strata have small denominators.

Analysis of an anti-progesterone antibody: variable crystal morphology of the Fab' and steroid-Fab' complexes.

Anti-progesterone monoclonal antibodies are being used for structural studies of antibody-antigen interaction, for their ability to block pregnancy shortly after fertilization, and for hormone immunoassay. A mouse anti-progesterone monoclonal Fab' fragment has been crystallized in its native form and co-crystallized with seven different, but structurally related, steroids. The crystals show interesting preferences in their crystal morphology, depending on the bound steroid ligand.

Painful piezogenic pedal papules in patients with Ehlers-Danlos syndrome.

Painful piezogenic pedal papules were observed in 10 of 29 patients with Ehlers-Danlos syndrome. The diagnosis was made by examining each patient while he or she stood with full body weight on the heels and by observing the appearance of the painful papules on the medial, posterior, and lateral aspects of both heels. Biopsy specimens of papules demonstrated a thickened and dense dermis.

The 'epidemiologic necropsy'. Unexpected detections, demographic selections, and changing rates of lung cancer.

When rising rates of occurrence are reported for a particular disease, clinicians often cannot determine whether the disease has increased in actual occurrence or in the improved detection provided by better diagnostic technology and expanded access to medical care. The epidemiologic use of necropsy data, which might help answer these questions, has been inhibited by fears of bias in demographic and clinical selection of patients for necropsy. The demographic problem can be managed by suitable adjustment and standardization of the disease rates found at necropsy, and the clinical problem can be reduced or avoided by studying the rates with which the disease is found unexpectedly in necropsies performed for other, unrelated clinical reasons.

Isolation and characterisation of goat C-reactive protein.

A pentraxin was isolated from acute phase goat serum by its calcium-dependent affinity for agarose, and although it did not bind to phosphorylcholine immobilised on Sepharose, its binding to agarose was reversed by exposure to fluid phase phosphorylcholine. It was identified as goat C-reactive protein on the basis of its immunochemical cross-reactivity with human and bovine C-reactive protein. The molecule was composed of five identical, glycosylated, non-covalently associated subunits, each of molecular weight approx.

A reappraisal of the United Kingdom epidemic of fatal asthma. Can general mortality data implicate a therapeutic agent?

The 1960s epidemic of asthma deaths that affected young persons in England and Wales, as well as in other countries, was attributed to the effect of newly available pressurized aerosols containing sympathomimetic bronchodilators. The subsequent decision to ban the nonprescription sale of these agents in the United Kingdom represented a unique use of national and international mortality data. The application of such data for decisions about therapeutic agents has implications for the current rise of asthma deaths in New Zealand, for the recent United States regulatory action regarding the nonprescription sale of aerosolized bronchodilators, and for the appraisal of adverse reactions to other pharmaceutical substances.

Identification and isolation of two pentraxins from bovine serum.

Two distinct pentraxin proteins were isolated from bovine serum by calcium-dependent affinity chromatography on high pyruvate agarose gel. One of these proteins cross-reacted specifically with certain rabbit anti-human CRP antisera and was therefore designated as bovine CRP. The other cross-reacted specifically with a sheep anti-human SAP antiserum and was therefore designated as bovine SAP.