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1.
Philip Anglewicz Dana Sarnak Alison Gemmill Stan Becker 《Studies in family planning》2023,54(1):17-38
Although the reproductive calendar is the primary tool for measuring contraceptive dynamics in low-income settings, the reliability of calendar data has seldom been evaluated, primarily due to the lack of longitudinal panel data. In this research, we evaluated the reproductive calendar using data from the Performance Monitoring for Action Project. We used population-based longitudinal data from nine settings in seven countries: Burkina Faso, Nigeria (Kano and Lagos States), Democratic Republic of Congo (Kinshasa and Kongo Central Provinces), Kenya, Uganda, Cote d'Ivoire, and India. To evaluate reliability, we compared the baseline cross-sectional report of contraceptive use (overall and by contraceptive method), nonuse, or pregnancy with the retrospective reproductive calendar entry for the corresponding month, measured at follow-up. We use multivariable regressions to identify characteristics associated with reliability or reporting. Overall, we find that the reliability of the calendar is in the “moderate/substantial” range for nearly all geographies and tests (Kappa statistics between 0.58 and 0.81). Measures of the complexity of the calendar (number of contraceptive use episodes, using the long-acting method at baseline) are associated with reliability. We also find that women who were using contraception without their partners/husband's knowledge (i.e., covertly) were less likely to report reliably in several countries. 相似文献
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Edward De Wolf Karel Claes Casper E. Sommeling Dries Opsomer Mario Cherubino Salvatore Vieni Stan Monstrey Salvatore D’Arpa 《The journal of sexual medicine》2019,16(7):1111-1117
IntroductionThe free radial forearm (FRFA) flap is universally still considered as the gold standard technique in penile reconstruction. Typically, a considerably large flap is required, often involving almost the entire circumference of the forearm. Partial necrosis may occur at the distal-most (dorsoradial) part of the flap as a result of insufficient perfusion.AimTo describe a new technique using the posterior interosseous artery (PIOA) to supercharge FRFA phalloplasty.MethodsIn a 12-month period, all patients having FRFA flap phalloplasty were enrolled. Perioperative, after complete flap dissection, an indocyanine green perfusion scan was performed. In case of insufficient perfusion at the distalmost part of the flap, a supramicrosurgical anastomosis was performed between the FRFA pedicle and the PIOA (artery only).Main Outcome MeasuresStudied outcomes included the rate of marginal necrosis, surgical time, postoperative posterior interosseous nerve damage and urethral complications (fistula, stenosis or necrosis).ResultsA total of 27 FRFA flap phalloplasties was performed. Anastomosis of the PIOA was needed in 15 cases. No marginal necrosis was observed in these cases. There were no cases of postoperative posterior interosseous nerve damage. There were no significant differences in urethral complications (fistula, stenosis or necrosis) between the 2 groups.Clinical ImplicationsIn selected cases where insufficient perfusion of the dorsoradial part of the flap is present, patients may benefit from arterial supercharging to prevent postoperative marginal necrosis.Strength & LimitationsStrengths include a single surgeon, thus lending continuity of skill and technique, a consecutive series, and 100% short-term follow-up. Limitations include single institution series and a limited number of patients.ConclusionArterial supercharging is effective in improving perfusion of large FRFA flaps used in phalloplasty when dorsoradial hypoperfusion is detected on an indocyanine green perfusion scan. It is a technically challenging addition to the standard technique because of the small size of the vessels, the close relationship between the PIOA and the posterior interosseous nerve, and the vulnerability of the newly constructed intra-flap anastomosis.De Wolf E, Claes K, Sommeling CE, et al. Free Bipedicled Radial Forearm and Posterior Interosseous Artery Perforator Flap Phalloplasty. J Sex Med 2019;16:1111–1117. 相似文献
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Martin F. Shapiro 《Journal of general internal medicine》2015,30(10):1392-1393
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Large quantities of data are now available to medical researchers; however, observational studies are plagued by bias and confounding. Additionally, much of this research only speculates on variable associations, leaving prospective randomized clinical trials as the sole purveyors of claims about causal relations between variables. There has been a growing movement of causal inference that uses new techniques to investigate causality using observational data. These techniques include the implementation of directed acyclic graphs, which allow researchers to explicitly and reproducibly define the causal relationships between study variables, thus making statistical analysis more robust. Directed acyclic graphs further allow researchers to identify confounding and other sources of bias and to discover causal effects among complex networks of variables. This review aims to introduce these techniques to the general urology and urologic oncology research communities in order to provide a basic understanding of causal inference and analysis and call for integration of these practices more generally in research methodology. 相似文献