Factorial design is an important method for optimizing complex strategies in implementation science. This paper systematically elucidates the origin, types, and core concepts of the factorial design, and then use a brief smoking cessation intervention project as an example to illustrate its specific applications in identifying key factors and testing interactions. Factorial design has the following typical advantages: it can test synergistic and antagonistic effects between factors, provide effect estimates that are broadly valid across the experimental conditions, and offer high statistical efficiency. At the same time, it also has certain limitations, including that its complexity is positively correlated with the number of factors, the need for large sample sizes to detect interactions, the potential for insufficient acceptability of some strategy combinations due to ethical concerns or participant burden, and the complexity of the analytical methods required. In future research, its application should be further optimized by appropriately controlling the number of factors, clearly defining research objectives, and evaluating intervention acceptability, in order to promote the development of precision implementation science.

Objective:To compare the efficacy and safety of endoscopic mucosal resection (EMR), EMR with pre-cutting (EMR-P), endoscopic submucosal dissection (ESD) and ESD with snare (ESD-S) for the treatment of colorectal laterally spreading tumors (LSTs).Methods:Between January 2016 and March 2018, a total of 146 patients with 146 colorectal LSTs undergone endoscopic resection at the first medical center of PLA General Hospital. Data of demographics, treatment information, pathology and follow-up results were retrospectively analyzed.Results:Among the 146 patients, EMR, EMR-P, ESD, and ESD-S were performed in 23, 29, 50 and 44 tumors, respectively. Median tumor diameter was 2.5 cm (ranged 1.2-10.0 cm). The en bloc resection rate of EMR, EMR-P, ESD and ESD-S were 73.9% (17/23), 72.4% (21/29), 96.0% (48/50), and 65.9% (29/44), respectively, with statistical difference ( P<0.001). And the R0 resection rate were 65.2% (15/23), 69.0% (20/29), 94.0% (47/50), and 63.6% (28/44), respectively, with statistical difference ( P=0.002). The en bloc resection rate and R0 resection rate of the ESD group were significantly higher than those of the other three groups (all P<0.05). The difference was not statistically significant in terms of perforation rate [0, 0, 6.0% (3/50), and 9.1% (4/44), respectively, P=0.269] and delayed hemorrhage rate [4.3% (1/23), 0, 2.0% (1/50), and 2.3% (1/44), respectively, P=0.768] among the four groups. Follow-up endoscopy was performed in 117 cases (80.1%) with a median period of 10.0 months (ranged 3.0-26.0 months), and local recurrence was identified in 7 (6.0%) cases. Conclusion:ESD could be the optimal method for the resection of colorectal LSTs, while LSTs smaller than 20 mm can be resected by EMR. EMR-P and ESD-S as modified methods have their respective advantages for the treatment of LSTs.

Objective To investigate the recurrence and risk factors of gastric high-grade intraepithelial neoplasia(HGIN)and early gastric cancer(EGC)after endoscopic submucosal dissection (ESD). Methods The clinical and follow-up data on 444 patients(451 lesion)with HGIN and EGC undergoing ESD in Digestive Endoscopy Center of Chinese PLA General Hospital from November 2006 to January 2016 were summarized, and the risk factors of recurrence were analyzed. Results A total of 410 patients were followed-up, and the recurrence rate was 3.2%(13 patients, 13 lesions), with mean recurrence time of 17.6±9.6 months(6-38 months). Univariate and multivariate analysis revealed that the size of the lesion>4.0 cm was the only risk factor of recurrence(P=0.012,OR=10.855,95%CI:1.673~70.442). Conclusion The rate of recurrence is increasing with the EGC extending, therefore, postoperative monitoring should be strengthened to patients with larger lesion.

Objective To assess the clinical value and safety of endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) for duodenal lesions.Methods The data of 12 patients with duodenal space-occupying lesions underwent EMR or ESD from January 2010 to December 2015 in Chinese PLA General Hospital were retrospectively analysed.Results All patients received operation, including 9 male and 3 female with mean age of 50.0 years(33.0-62.0 years).There were 8 lesions in duodenal bulb and 4 in descending part.The mean diameter of the lesions was 1.2 cm (0.5-3.0 cm).Three lesions were originated from mucosa, of which 2 were high-grade intraepithelial neoplasia and 1 was villous/tubular adenoma.Nine lesions were located in submucosa, including 3 cases of neuroendocrine neoplasm, 1 case of stromal tumor, 1 liomyoma case, 1 lipoma case, 1 case of Brunner glands adenoma, 1 case of ectopic pancreas, and 1 inflammatory lesion.One patient had perforation with rate of 8.3%(1/12) and was recovered after conserved treatment.The bleeding was very little during operation.No infection or stenosis happened.The mean hospitalized time was 6.0 days (1.0-12.0 days) after operation.No recurrence was found during 23.8 months(3.0-73.0 months) of follow-up.Conclusion EMR and ESD are effective and safe for treatment of duodenal space-occupying lesions.

BACKGROUNDEndoscopic submucosal dissection of the esophagogastric junction is the most difficult gastric and esophageal dissection procedure. No reports of endoscopic submucosal dissection for Siewert type II carcinoma of the esophagogastric junction have compared the outcomes of endoscopic submucosal dissection for all three Siewert types of adenocarcinoma. This study aimed to evaluate the efficacy and safety of endoscopic submucosal dissection for intraepithelial neoplasia of the esophagogastric junction.

METHODSFrom October 2008 to June 2013, 73 patients underwent endoscopic submucosal dissection for intraepithelial neoplasia of the esophagogastric junction. The patients were prospectively evaluated regarding the executability of the technique, short-term results of the procedure, en bloc resection rate, curative resection rate, complications and additional treatment after endoscopic submucosal dissection, and follow-up outcomes.

RESULTSSixty-eight of the 73 patients (93.2%) underwent en bloc resection; the mean maximum specimen diameter was 33.7 mm. Fifty-seven of 61 patients (93.4%) who underwent curative resection were successfully followed-up for 1.0 to 56.0 months (average, 24.1 months). Local recurrence developed in one patient with high-grade intraepithelial neoplasm. Twelve patients underwent noncurative resection, including lateral resection margin residues in three, vertical resection margin residues in one, signet ring cell carcinoma or undifferentiated adenocarcinoma in four, lymphatic or vessel invasion in one, vertical residual margin residues combined with signet ring cell carcinoma in one, and undifferentiated adenocarcinoma with lymphatic or vessel invasion in two. In the noncurative resection group, one patient was lost to follow-up, seven underwent additional surgery, and the remaining four were periodically followed up; none had local recurrence or distant metastases. The only complication was delayed bleeding in three patients, which was successfully controlled by conservative treatment or endoscopic therapy.

CONCLUSIONSEndoscopic submucosal dissection is safe and effective for intraepithelial neoplasia of the esophagogastric junction. R0 en bloc resection is possible and can avoid the risk of local recurrence.

Adult ; Aged ; Aged, 80 and over ; Carcinoma in Situ ; surgery ; Dissection ; adverse effects ; methods ; Esophageal Neoplasms ; surgery ; Esophagogastric Junction ; surgery ; Female ; Gastric Mucosa ; surgery ; Humans ; Male ; Middle Aged ; Prospective Studies

Objective To investigate the incidence,location and morphological features of Laimer fibers between mucosal layer and inner circular muscularispropria in patients with achalasia.Methods Data of 107 patients with achalasia who underwent POEM between May 2010 and June 2013 were collected.Endoscopic video was reviewed to determine the incidence of Laimer fibers and the corresponding images were analyzed according to gender,age,Ling typing and location of Laimer fibers.Results Laimer fibers were found in lower esophageal sphincter of 44 patients (41.12％).There were no significant differences in the incidences of Laimer fiber among groups with different age or gender (P ＞ 0.05).The incidence in Ling type Ⅱb was 46.15％ (12/26),and 45.83％ (22/48) in Ling type Ⅰ,0 in Ling type Ⅲ.There was no significant difference among the groups of Ling type (x2 =2.042,P =0.564).All Laimer fibers were found in lower esophageal sphincter and the majority of which were in right wall (36.45 ％,39/107),followed by left wall (3.74％,4/107) and none was found in anterior wall (x2 =107.468,P =0.000).Conclusion Laimer fibers generally exists in lower esophageal sphincter and most of which are discovered on right wall of the esophagus.Further study is needed to explore its role in development and treatment of achalasia.

Objective To evaluate the curative effect of asymptotic full-thickness myotomy type of peroral endoscopic myotomy(POEM) for achalasia.Methods Data of 41 patients who underwent asymptotic POEM at our digestive endoscopy center from December 10th 2010 to January 10th 2014 were retrospectively studied.The postoperative and preoperative symptoms and reflux were compared.Results The postoperative Eckardt scores of symptoms of 41 patients improved significantly(P ＜ 0.001) compared with before.Esophageal dynamic pressure also showed the effectiveness of symptom relief.The incidence of postoperative reflux in symptoms and gastroscopy were 26.83％ and 27.27％,respectively.Conclusion Asymptotic fullthickness myotomy POEM can alleviate the symptoms of achalasia and the effect of inhibiting reflux is generally satisfactory.

OBJECTIVETo compare the safety and efficiency of endoscopic submucosal tunnel dissection (ESTD) and endoscopic submucosal dissection (ESD) for large esophageal superficial neoplasms.

METHODSA total of 235 consecutive patients undergoing endoscopic resection for esophageal neoplasms between October, 2010 and June, 2013 in our endoscopy center were analyzed retrospectively. According to the inclusion and exclusion criteria, 29 patients receiving ESTD or ESD for large esophageal superficial neoplasms were enrolled for data analysis.

RESULTSOf the 29 patients, 11 underwent ESTD and 18 received ESD. The dissection speed of ESTD was significantly higher than that of ESD (22.4∓5.2 mm(2)/min vs 12.2∓4.0 mm(2)/min, P<0.05). Despite a similar en bloc rate between the two groups (100% [11/11] vs 88.9% [16/18], P>0.05), the radical curative rate of ESTD was significantly greater than that of ESD (81.8% [9/11] vs 66.7% [12/18], P<0.05). No serious bleeding or perforation occurred in the patients except for 1 in ESD group with intraoperative bleeding, which was managed with hemostatic forceps. Eight patients had postoperative esophageal strictures in relation with circumferential extension and the longitudinal length (P<0.05).

CONCLUSIONESTD is a safe and effective alternative for large esophageal superficial neoplasms with a shortened operative time, a higher dissection speed and a higher radical curative rate in comparison with ESD, but postoperative esophageal strictures should be closely monitored especially for lesions more than 3/4 of the circumferential extension or exceeding 50 mm.

Aged ; Endoscopy ; Esophageal Neoplasms ; surgery ; Esophagus ; surgery ; Female ; Humans ; Male ; Middle Aged ; Mucous Membrane ; surgery ; Retrospective Studies

Objective To compare the safety and efficiency of endoscopic submucosal tunnel dissection (ESTD) and endoscopic submucosal dissection (ESD) for large esophageal superficial neoplasms. Methods A total of 235 consecutive patients undergoing endoscopic resection for esophageal neoplasms between October, 2010 and June, 2013 in our endoscopy center were analyzed retrospectively. According to the inclusion and exclusion criteria, 29 patients receiving ESTD or ESD for large esophageal superficial neoplasms were enrolled for data analysis. Results Of the 29 patients, 11 underwent ESTD and 18 received ESD. The dissection speed of ESTD was significantly higher than that of ESD (22.4±5.2 mm2/min vs 12.2±4.0 mm2/min, P<0.05). Despite a similar en bloc rate between the two groups (100%[11/11]vs 88.9%[16/18], P>0.05), the radical curative rate of ESTD was significantly greater than that of ESD (81.8%[9/11]vs 66.7%[12/18], P<0.05). No serious bleeding or perforation occurred in the patients except for 1 in ESD group with intraoperative bleeding, which was managed with hemostatic forceps. Eight patients had postoperative esophageal strictures in relation with circumferential extension and the longitudinal length (P<0.05). Conclusions ESTD is a safe and effective alternative for large esophageal superficial neoplasms with a shortened operative time, a higher dissection speed and a higher radical curative rate in comparison with ESD, but postoperative esophageal strictures should be closely monitored especially for lesions more than 3/4 of the circumferential extension or exceeding 50 mm.

Objective To compare the safety and efficiency of endoscopic submucosal tunnel dissection (ESTD) and endoscopic submucosal dissection (ESD) for large esophageal superficial neoplasms. Methods A total of 235 consecutive patients undergoing endoscopic resection for esophageal neoplasms between October, 2010 and June, 2013 in our endoscopy center were analyzed retrospectively. According to the inclusion and exclusion criteria, 29 patients receiving ESTD or ESD for large esophageal superficial neoplasms were enrolled for data analysis. Results Of the 29 patients, 11 underwent ESTD and 18 received ESD. The dissection speed of ESTD was significantly higher than that of ESD (22.4±5.2 mm2/min vs 12.2±4.0 mm2/min, P<0.05). Despite a similar en bloc rate between the two groups (100%[11/11]vs 88.9%[16/18], P>0.05), the radical curative rate of ESTD was significantly greater than that of ESD (81.8%[9/11]vs 66.7%[12/18], P<0.05). No serious bleeding or perforation occurred in the patients except for 1 in ESD group with intraoperative bleeding, which was managed with hemostatic forceps. Eight patients had postoperative esophageal strictures in relation with circumferential extension and the longitudinal length (P<0.05). Conclusions ESTD is a safe and effective alternative for large esophageal superficial neoplasms with a shortened operative time, a higher dissection speed and a higher radical curative rate in comparison with ESD, but postoperative esophageal strictures should be closely monitored especially for lesions more than 3/4 of the circumferential extension or exceeding 50 mm.