Randomized trial comparing the 25G and 22G Franseen needles in endoscopic ultrasound-guided tissue acquisition from solid pancreatic masses for adequate histological assessment.

BACKGROUND: The effects of the Franseen needle size in endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) of solid pancreatic masses remain unclear. This study aimed to compare 25G and 22G Franseen needles in terms of adequate tissue acquisition from solid pancreatic masses. METHODS: In this single-center, crossover, randomized noninferiority trial, eligible patients underwent EUS-FNB with both 25G and 22G Franseen needles in a randomized order between November 2018 and August 2020. Tissue specimens from each pass were separately evaluated based on the cellularity scoring system. The primary outcome was the proportion of acquired specimens allowing adequate histological assessment (cellularity score ≥3). A -15% noninferiority margin was assumed. RESULTS: Data from 88 patients were analyzed, which showed malignant and benign lesions in 84 (95.5%) and four (4.5%) patients, respectively. Of the 88 specimens, 62 (70.5%) and 69 (78.4%) acquired using 25G and 22G needles, respectively, allowed adequate histological assessment. The adjusted proportion difference was -6.6% (95% confidence interval -8.8% to -4.5%), indicating noninferiority of the 25G Franseen needle (P < 0.001). The diagnostic accuracies of the 25G and 22G needles were 86.4% and 89.8%, respectively, with no significant difference (P = 0.180). Adverse events occurred in one patient. CONCLUSIONS: The 25G Franseen needle showed a noninferior adequate tissue acquisition and similar diagnostic performance compared to that of the 22G Franseen needle. However, a 15% noninferiority margin was high for clinical use; thus, further consideration is needed (Clinical Trial Registry no. UMIN000034596).

A typology of four notions of confounding in epidemiology.

Confounding is a major concern in epidemiology. Despite its significance, the different notions of confounding have not been fully appreciated in the literature, leading to confusion of causal concepts in epidemiology. In this article, we aim to highlight the importance of differentiating between the subtly different notions of confounding from the perspective of counterfactual reasoning. By using a simple example, we illustrate the significance of considering the distribution of response types to distinguish causation from association, highlighting that confounding depends not only on the population chosen as the target of inference, but also on the notions of confounding in distribution and confounding in measure. This point has been relatively underappreciated, partly because some literature on the concept of confounding has only used the exposed and unexposed groups as the target populations, while it would be helpful to use the total population as the target population. Moreover, to clarify a further distinction between confounding "in expectation" and "realized" confounding, we illustrate the usefulness of examining the distribution of exposure status in the target population. To grasp the explicit distinction between confounding in expectation and realized confounding, we need to understand the mechanism that generates exposure events, not the product of that mechanism. Finally, we graphically illustrate this point, highlighting the usefulness of directed acyclic graphs in examining the presence of confounding in distribution, in the notion of confounding in expectation.

Preoperative graft volume assessment with 3D-CT volumetry in living-donor lobar lung transplantations.

To determine the effectiveness of living-donor lobar lung transplantation (LDLLT), it is necessary to predict the recipient's postoperative lung function. Traditionally, Date's formula, also called the segmental ratio, has used the number of lung segments to estimate the forced vital capacity (FVC) of grafts in LDLLT. To provide a more precise estimate of graft FVC, we calculated the volumes of the lower lobe and total lung using three-dimensional computed tomography (3D-CT) and the volume ratio between them. We calculated the volume ratio in 52 donors and tested the difference between the segmental volume ratios with a one-tailed t-test. We also calculated the predicted graft FVC in 21 LDLLTs using the segmental ratio pFVC(c) and the volume ratio pFVC(v), and then found the Pearson's correlation coefficients for both pFVC(c) and pFVC(v) with the recipients' actual FVC (rFVC) measured spirometrically 6 months after surgery. Significant differences were found between the segmental ratio and the average volume ratio for both sides (right, p＝0.03;left, p＝0.0003). Both pFVC(c) and pFVC(v) correlated significantly with rFVC at 6 months after surgery (p＝0.007 and 0.006). Both the conventional and the volumetric methods provided FVC predictions that correlated significantly with measured postoperative FVC.

[Utilization, needs, and related factors for e-learning and its application to education and training in occupational safety and health among enterprises in Japan].

In order to know utilization, needs, and related factors for e-learning and its application to education and training in occupational safety and health (OSH) among enterprises in Japan, a questionnaire survey was conducted of enterprises randomly selected from those with 1,000 or more employees and those with 999 or less (500 for each). Data from 134 (56 and 78, respectively) enterprises were analyzed (response rate, 13%). Among total enterprises, 19% had introduced and 16% planned to introduce e-learning. However, only 7% of larger enterprises and less than 3% of smaller enterprises used e-learning for education and training in OSH. On the other hand, 80-90% of enterprises responded positively to considering the use of e-learning for education and training on various OSH topics for various users. Highly rated merits of e-learning were "can use whenever", "can use anywhere"; and its highly rated obstacles were "cost", "individual PC not available", "insufficient information on efficacy". However, the merit "can monitor training" was significantly associated with the use/plan of e-learning. "Good contents not available" was more frequent among enterprises which used/planned e-learning. The study indicated a greater need for e-learning based OSH education and training, despite a currently low rate of its use. Improvement of e-learning platforms and contents, reduction of cost, and improvement of e-learning infrastructure at work may be needed to facilitate the use of e-learning in OSH.