Addressing Methodologic Challenges and Minimizing Threats to Validity in Synthesizing Findings from Individual-Level Data Across Longitudinal Randomized Trials

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.

     

Usefulness of Intraoperative Continuous Infusion of Tranexamic Acid during Emergency Surgery for Type A Acute Aortic Dissection

Purpose: We investigated the influence of intraoperative continuous tranexamic acid (TA) infusion on the amount of blood transfusion required in emergency surgery for type A acute aortic dissection.Methods: The study was based on the data of 55 consecutive patients who underwent surgery for type A acute aortic dissection. The patients were divided into 2 groups for comparison: Group T, consisting of 26 patients who received intraoperative continuous infusion of TA, and Group N, consisting of 29 patients who did not receive TA infusion during the surgery.Results: The mean amounts of blood transfusion required during and after surgery were compared between the 2 groups: they were 10.5 ± 8.7 and 16.2 ± 10.0 units of mannitol-adenine-phosphate-added red cell concentrate, 9.3 ± 8.6 and 17.1 ± 10.0 units of fresh frozen plasma, and 20.4 ± 12.2 and 29.7 ± 14.9 units of platelet concentrate, respectively, in Groups T and N. Thus, the amount of each of these blood products required was significantly reduced in Group T.Conclusions: During emergency surgery for type A acute aortic dissection, continuous infusion of TA resulted in a significant reduction in the amount of blood transfusion required.     

Fabrication of a metal-ceramic crown to fit an existing partial removable dental prosthesis using ceramic pressed to metal technique: a clinical report

Fabricating a crown to retrofit an existing abutment tooth for a partial removable dental prosthesis (PRDP) is one of the most time-consuming and labor-intensive clinical procedures. In particular, when the patient is concerned with esthetic aspects of restoration, the task of fabricating becomes more daunting. Many techniques for the fabrication of all-metallic or metal-ceramic crowns have been discussed in the literature. This article was aimed to describe a simple fabrication method in which a retrofitting crown was fabricated for a precise fit using a ceramic-pressed-to-metal system.     

Retreatment using a dual mode of low-fluence Q-switched and long-pulse Nd:YAG laser in patients with melasma aggravation after previous therapy

Background: Aggravated melasma after treatment is vulnerable to stimulation, can easily deteriorate, and may be distressing without proper management. Objective: To retrospectively assess the effectiveness and safety of combination therapy using low-fluence Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) laser (QSNY) and long-pulse Nd:YAG laser (LPNY) (dual toning) in patients with rebound melasma. Materials and methods: A total of 30 patients with aggravated melasma after previous therapy who were treated with dual toning were enrolled. A total of 10 sessions were conducted at 1-week intervals, followed by maintenance treatment. The results were evaluated using the modified Melasma Area and Severity Index (mMASI) and the physician's global assessment (PGA) before and 2 months after completing the 10 treatment sessions. Results: The baseline mMASI was 10.48 ± 3.64, which significantly decreased to 3.22 ± 1.45 2 months after completing the 10 treatment sessions (p < 0.001). Twenty-four patients (80%) had PGA grade 4 (76–100% improvement) and 6 patients (20%) had PGA grade 3 (51–75% improvement). Conclusion: Dual toning may be a safe and effective salvage treatment for patients with aggravated melasma after previous treatment. LPNY may stabilize melasma activity to prevent rebound hyperpigmentation via dermal remodeling.     

Initial work-up for cervical lymphadenopathy: back to basics

The aim of this study was to evaluate the value of FNA, Tb-PCR, and CBC as an initial work-up protocol for cervical lymphadenopathy to reiterate the importance of CBC in terms of predicting the clinical course. In this consecutive case series, 158 patients with cervical lymphadenopathy were enrolled. All patients underwent FNA and CBC, with or without Tb-PCR. The validity of combined FNA?±?Tb-PCR and CBC in the diagnosis of diseases requiring definitive treatment was evaluated. Final diagnoses were self-limiting disease in 110 (69.6%), malignancy in 19 (12.0%), and tuberculosis in 26 (16.5%). Sensitivity of FNA?±?Tb-PCR was 66.7% and of added CBC profile was 97.9%. Patients with neutropenia or lymphocytosis were found to have a higher chance of spontaneous recovery than patients with a normal WBC profile. FNA and Tb-PCR were found to be important in patients aged more than 20. The results indicate that FNA, Tb-PCR, and CBC are basic and essential in initial work-up for cervical lymphadenopathy. In particular, CBC was found to aid in detecting critical diseases and predicting the likelihood of open biopsy in patients with negative FNA and Tb-PCR. Patient age was also found to be an important determinant of the work-up protocol.