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Background
Laparoscopic cholecystectomy (LC) is the standard operative intervention for gallbladder disease. Complications may necessitate conversion to an open cholecystectomy (OC). This study aims to determine the cost-consequences of laparoscopic-to-open conversion using a nationally-representative sample.Methods
Using the National Inpatient Sample (2007–2011), adult patients undergoing emergent LC were identified. Patients undergoing secondary-conversion to OC were subsequently identified. Multivariable regression analyses, accounting for differences in propensity-quintile, mortality, length of stay, and hospital-level factors were then performed to assess for differences in the odds of conversion and total predicted mean costs per index-hospitalization.Results
Of 225,805 observations, conversion to open occurred in 1.86% (n?=?4203) of cases. Increased age, African-American ethnicity, public-insurance and teaching-hospital status were associated with a higher likelihood of conversion (p?<?0.05) after risk-adjustment. Risk-adjusted odds of conversion increased by 34% (95%CI:1.33–1.36) for each day surgery was delayed. Risk-adjusted costs, were 259% higher (absolute-difference $23,358,p?<?0.05) with conversion. Mortality was higher amongst patients undergoing conversion to open (4.98% vs 0.34%,p?<?0.001).Conclusion
Patients undergoing conversion from laparoscopic to open cholecystectomy are at an increased risk of receiving disparate care and increased mortality. 相似文献Integrative Data Analysis (IDA) encompasses a collection of methods for data synthesis that pools participant-level data across multiple studies. Compared with single-study analyses, IDA provides larger sample sizes, better representation of participant characteristics, and often increased statistical power. Many of the methods currently available for IDA have focused on examining developmental changes using longitudinal observational studies employing different measures across time and study. However, IDA can also be useful in synthesizing across multiple randomized clinical trials to improve our understanding of the comprehensive effectiveness of interventions, as well as mediators and moderators of those effects. The pooling of data from randomized clinical trials presents a number of methodological challenges, and we discuss ways to examine potential threats to internal and external validity. Using as an illustration a synthesis of 19 randomized clinical trials on the prevention of adolescent depression, we articulate IDA methods that can be used to minimize threats to internal validity, including (1) heterogeneity in the outcome measures across trials, (2) heterogeneity in the follow-up assessments across trials, (3) heterogeneity in the sample characteristics across trials, (4) heterogeneity in the comparison conditions across trials, and (5) heterogeneity in the impact trajectories. We also demonstrate a technique for minimizing threats to external validity in synthesis analysis that may result from non-availability of some trial datasets. The proposed methods rely heavily on latent variable modeling extensions of the latent growth curve model, as well as missing data procedures. The goal is to provide strategies for researchers considering IDA.
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