An initial evaluation of a predoctoral general practice program.

The mechanism of ST-segment depression during exercise electrocardiographic treadmill testing (ETT) is unknown. The relatively good correlation between the results of ETT and myocardial perfusion imaging suggests that ST-segment depression may be related to the magnitude of ischemia. Previous studies that investigated this relation have produced conflicting results. We evaluated 1,006 patients who underwent symptom-limited ETT and technetium-99m single-photon emission computed tomographic myocardial perfusion imaging at rest and during stress at a single institution. The magnitude, extent, and duration of ST-segment depression were each strongly associated with the magnitude of myocardial ischemia (p <0.001 for all). The magnitude, extent, and duration of ST-segment depression were highly correlated with each other and had similar relations to the magnitude of ischemia. After adjustment for significant clinical and ETT parameters, these relations remained highly significant. The location of myocardial ischemia was unrelated to ST-segment depression. This large study found that ST-segment depression during ETT is strongly associated with the magnitude of ischemia. These data support a causative role for the magnitude of ischemia in the generation of ST-segment depression.

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PubMed2004

Testing for Hardy-Weinberg equilibrium in samples with related individuals.

When the classical chi(2) goodness-of-fit test for Hardy-Weinberg (HW) equilibrium is used on samples with related individuals, the type I error can be greatly inflated. In particular the test is inappropriate in population isolates where the individuals are related through multiple lines of descent. In this article, we propose a new test for HW (the QL-HW test) suitable for any sample with related individuals, including large inbred pedigrees, provided that their genealogy is known. Performed conditional on the pedigree structure, the QL-HW test detects departures from HW that are not due to the genealogy. Because the computation of the QL-HW test becomes intractable for very polymorphic loci in large inbred pedigrees, a simpler alternative, the GCC-HW test, is also proposed. The statistical properties of the QL-HW and GCC-HW tests are studied through simulations considering a sample of independent nuclear families, a sample of extended outbred genealogies, and samples from the Hutterite population, a North American highly inbred isolate. Finally, the method is used to test a set of 143 biallelic markers spanning 82 genes in this latter population.

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PubMed2004

[An educational training program for physicians for diagnosis and treatment of depression].

OBJECTIVE: The American Regional Office of the WHO has launched a major initiative to reduce the prevalence of affective disorders region-wide that includes focusing on the primary health care system. This study evaluated the results of an educational training program for Brazilian primary care physicians that measured changes in knowledge, attitudes, and practice. METHODS: A total of 17 primary care physicians and 1,224 patients participated in the study. Physician's knowledge, attitudes, and clinical practice were assessed one-month prior and one-month following the training program. In addition, the patients that visited the clinic during a typical week completed depression symptom self-ratings, including the Zung and a DSM-IV/ICD-10 major depression checklist at both times. RESULTS: The training program showed limited benefits in this small sample of physicians. The program was unable to demonstrate benefit in improving knowledge about depression and in changing disorder-related attitudes. There were no changes in the diagnostic rates of major depression. There was some evidence to support improvement in psychopharmacological management. The physicians seemed more confident in treating patients, as there was a reduction of referrals to the specialists. Lack of statistical power prevented the latter two findings from reaching statistical significance. CONCLUSIONS: The inclusion of primary care physicians is a central component of any initiative to reduce the treatment gap and lag of depression. However, more effective methods of training Brazilian primary care physicians in the management of major depression need to be tested.

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