Articles: prospective-studies.
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Erroneous time documentation of emergency treatment caused by the variation in the accuracy of timepieces has profound medical, medicolegal, and research consequences. The purpose of this study was to confirm the variation of critical timepiece settings in an urban emergency care system noted in previous studies and to implement and monitor the results of a prospective program to improve time synchronization. ⋯ Emergency medical timepieces are often inaccurate, making it difficult to reconstruct events for medical, medicolegal, or research purposes. Community synchronization of timepieces to the atomic clock can reduce the problem significantly, but the effects of a one-time attempted synchronization event are short-lived. [Ornato JP, Doctor ML, Harbour LF, Peberdy MA, Overton J, Racht EM, Zauhar WG, Smith AP, Ryan KA: Synchronization of time-pieces to the atomic clock in an urban emergency medical services system. Ann Emerg Med April 1998;31:483-487.].
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To examine rates of HIV-1 and sexually transmitted disease (STD) among pregnant and postpartum women in urban Malawi, Africa. ⋯ Among urban childbearing women in Malawi, incidence of HIV is highest among young women while, currently, prevalence is highest among older women. Recent declines in STD prevalence suggest that HIV prevention programs are having an impact either through improved STD diagnosis and treatment or reduced risk behaviors. Sequential cross-sectional STD prevalence measures may be useful in monitoring effectiveness of STD and HIV prevention activities.
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To assess the effects of HIV-1 and other sexually transmitted infections on pregnancy, we undertook cross-sectional and prospective studies of a rural population in Rakai district, Uganda. ⋯ Pregnancy prevalence is greatly reduced in HIV-1-infected women, owing to lower rates of conception and increased rates of pregnancy loss. HIV-1 surveillance confined to pregnant women underestimates the magnitude of the HIV-1 epidemic in the general population.
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Epidemiologic reviews · Jan 1998
ReviewExposure measurement in cohort studies: the challenges of prospective data collection.
Cohort study designs have several advantages over case-control studies in terms of exposure measurement. If exposure measurement occurs before disease occurrence, cohort studies are much less prone to differential measurement error. Prospective data collection should also reduce measurement error due to poor recall of past exposures. ⋯ Long-term cohort studies which cover the etiologically relevant time period could improve the accuracy of measures of exposures by use of repeated biologic measures or repeated updates of self-reported exposures. Measurement error also can be reduced by judicious choice of a cohort to study and by careful attention to quality control procedures. Continued emphasis on the evaluation and improvement of the measurement properties of instruments used in epidemiologic studies will improve the validity of the results of cohort studies.
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To compare the efficacy of the Valsalva maneuver with that of carotid sinus massage (CSM) in terminating paroxysmal supraventricular tachycardia (SVT) in the ED. ⋯ Vagal maneuvers are efficacious in terminating about one quarter of spontaneous SVT cases. There is no detectable difference in efficacy between the Valsalva maneuver and CSM. [Lim SH, Anantharaman V, Teo WS, Goh PP, Tan ATH: Comparison of treatment of supraventricular tachycardia by Valsalva maneuver and carotid sinus massage. Ann Emerg Med January 1998;31:30-35.].