Purpose: Long-course chemoradiotherapy (LCRT) has been widely recommended in a majority of rectal cancer patients. Recently, encouraging data on short-course radiotherapy (SCRT) for rectal cancer has emerged. In this study, we aimed to compare these two methods in terms of short-term outcomes and cost analysis under the Korean medical insurance system. Materials and Methods: Sixty-two patients with high-risk rectal cancer, who underwent either SCRT or LCRT followed by total mesorectal excision (TME), were classified into two groups. Twenty-seven patients received 5 Gy×5 with two cycles of XELOX (capecitabine 1000 mg/m 2 and oxaliplatin 130 mg/m 2 every 3 weeks) followed by TME (SCRT group). Thirty-five patients received capecitabine-based LCRT followed by TME (LCRT group). Short-term outcomes and cost estimation were assessed between the two groups. Results: Pathological complete response was achieved in 18.5% and 5.7% of patients in the SCRT and LCRT groups, respectively (p=0.223). The 2-year recurrence-free survival rate did not show significant difference between the two groups (SCRT vs. LCRT:91.9% vs. 76.2%, p=0.394). The average total cost per patient for SCRT was 18% lower for inpatient treatment (SCRT vs. LCRT: $18787 vs. $22203, p<0.001) and 40% lower for outpatient treatment (SCRT vs. LCRT: $11955 vs. $19641, p<0.001) compared to LCRT. SCRT was shown to be the dominant treatment option with fewer recurrences and fewer complications at a lower cost. Conclusion SCRT was well-tolerated and achieved favorable short-term outcomes. In addition, SCRT showed significant reduction in the total cost of care and distinguished cost-effectiveness compared to LCRT.

Background: The lack of well-established operational definitions is a major limitation of Helicobacter pylori eradication studies that use secondary databases. We aimed to develop and validate operational definitions related to H. pylori eradication therapy. Methods: Operational definitions were developed by analyzing a nationwide H. pylori eradication registry and validated using real-world data from hospital medical records. The primary endpoint was the sensitivity of the operational definitions in identifying individuals who received H. pylori eradication therapy. The secondary endpoint was the sensitivity and specificity of the operational definition in identifying successful H. pylori eradication therapy. Results: H. pylori eradication therapy was defined as a prescription for one of the following combinations: 1) proton pump inhibitor (PPI) + amoxicillin + clarithromycin, 2) PPI + amoxicillin + metronidazole, 3) PPI + metronidazole + tetracycline, 4) PPI + amoxicillin + levofloxacin, 5) PPI + amoxicillin + moxifloxacin, or 6) PPI + amoxicillin + rifabutin. In the validation set, the sensitivity of the operational definition for identifying individuals who received H. pylori eradication therapy was 99.7% and 99.8% for the first- and second-line therapies, respectively. Operational definition to determine success or failure of the H. pylori eradication therapy was developed based on a confirmatory test and the prescription of rescue therapy. The sensitivity and specificity of the operational definition for predicting successful eradication were 97.6% and 91.4%, respectively, in first-line therapy and 98.6% and 54.8%, respectively, in second-line therapy. Conclusion We developed and validated operational definitions related to H. pylori eradication therapy. These definitions will help researchers perform various H. pylori eradication-related studies using secondary databases.

Objectives: . The impacts of ventilation tube (VT) type and effusion composition on the VT extrusion rate and complications in children with otitis media remain unclear. This part II study evaluated the factors affecting the extrusion rate, recurrence rate, and complications of VT insertion. Methods: . A prospective study was conducted between June 2014 and December 2016 (the EVENT study [analysis of the effectiveness of ventilation tube insertion in pediatric patients with chronic otitis media]), with follow-up data collected until the end of 2017. Patients aged <15 years diagnosed with otitis media with effusion who received VT insertion were recruited at 15 tertiary hospitals. The primary outcomes were time to extrusion of VT, time to effusion recurrence, and complications. Results: . Data from 401 patients were analyzed. After excluding the results of long-lasting tubes (Paparella type II and T-tubes), silicone tubes (Paparella type I) exhibited a significantly longer extended time to extrusion (mean, 400 days) than titanium tubes (collar-button-type 1.0 mm: mean, 312 days; P<0.001). VT material (hazard ratio [HR], 2.117, 95% confidence interval [CI], 1.254–3.572; P=0.005), age (HR, 3.949; 95% CI, 1.239–12.590; P=0.02), and effusion composition (P=0.005) were significantly associated with the time to recurrence of middle ear effusion. Ears with purulent (mean, 567 days) and glue-like (mean, 588 days) effusions exhibited a shorter time to recurrence than ears with serous (mean, 846 days) or mucoid (mean, 925 days) effusions. The revision VT rates during follow-up were 3.5%, 15.5%, 10.4%, and 38.9% in ears with serous, mucoid, glue-like, and purulent effusions, respectively (P<0.001). The revision surgery rates were higher among patients aged <7 years than among those aged ≥7 years. Conclusion . Silicone tubes (Paparella type I) were less prone to early extrusion than titanium 1.0 mm tubes. VT type, patient age, and effusion composition affected the time to recurrence of effusion.

Helicobacter pylori (H. pylori) infection is one of the most common infectious diseases worldwide. Although its incidence is gradually decreasing, about half of the world's population still get infected. H. pylori infection is responsible for substantial gastrointestinal morbidity worldwide. It is the most common cause of gastric and duodenal ulcers as well as gastric cancer. Since the revision of the H. pylori Clinical Practice Guidelines in 2013, the eradication rate of H. pylori has gradually decreased with the use of classical triple therapy, wherein amoxicillin, clarithromycin, and proton pump inhibitors are administered, for 7 days. According to a nationwide randomized controlled study conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research released in 2018, the intention-to-treat eradication rate was only 63.9%, which was due to increased antimicrobial resistance induced by the use of antibiotics, especially clarithromycin. The update of clinical practice guideline for treatment of H. pylori was developed based on evidence-based medicine by conducting a meta-analysis. The draft recommendations were finalized after expert consensus on three recommendations regarding the indication for treatment and eight recommendations on the treatment itself. These guidelines are designed to provide patients, nurses, medical school students, policymakers, and clinicians with clinical evidence to guide primary care and treatment of H. pylori infection. These may differ from current medical insurance standards and will be revised further, if necessary, based on research-based evidence.

The Korean Intermittent Exotropia Multicenter Study (KIEMS), which was initiated by the Korean Association of Pediatric Ophthalmology and Strabismus, is a collaborative multicenter study on intermittent exotropia in Korea. The KIEMS was designed to provide comprehensive information, including subjective and objective findings of intermittent exotropia in a large study population. A total of 65 strabismus specialists in 53 institutions contributed to this study, which, to date, is one of the largest clinical studies on intermittent exotropia. In this article, we provide a detailed methodology of the KIEMS to help future investigations that may use the KIEMS data.

Helicobacter pylori (H. pylori) infection is one of the most common infectious diseases worldwide. Although its incidence is gradually decreasing, about half of the world's population still get infected. H. pylori infection is responsible for substantial gastrointestinal morbidity worldwide. It is the most common cause of gastric and duodenal ulcers as well as gastric cancer. Since the revision of the H. pylori Clinical Practice Guidelines in 2013, the eradication rate of H. pylori has gradually decreased with the use of classical triple therapy, wherein amoxicillin, clarithromycin, and proton pump inhibitors are administered, for 7 days. According to a nationwide randomized controlled study conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research released in 2018, the intention-to-treat eradication rate was only 63.9%, which was due to increased antimicrobial resistance induced by the use of antibiotics, especially clarithromycin. The update of clinical practice guideline for treatment of H. pylori was developed based on evidence-based medicine by conducting a meta-analysis. The draft recommendations were finalized after expert consensus on three recommendations regarding the indication for treatment and eight recommendations on the treatment itself. These guidelines are designed to provide patients, nurses, medical school students, policymakers, and clinicians with clinical evidence to guide primary care and treatment of H. pylori infection. These may differ from current medical insurance standards and will be revised further, if necessary, based on research-based evidence.

The Korean Intermittent Exotropia Multicenter Study (KIEMS), which was initiated by the Korean Association of Pediatric Ophthalmology and Strabismus, is a collaborative multicenter study on intermittent exotropia in Korea. The KIEMS was designed to provide comprehensive information, including subjective and objective findings of intermittent exotropia in a large study population. A total of 65 strabismus specialists in 53 institutions contributed to this study, which, to date, is one of the largest clinical studies on intermittent exotropia. In this article, we provide a detailed methodology of the KIEMS to help future investigations that may use the KIEMS data.

Background/Aims: Standard triple therapy, including a proton pump inhibitor, clarithromycin, and amoxicillin, has been recommended as the first-line for Helicobacter pylori infection. However, the eradication rate of standard triple therapy has declined over the past years because of the increasing resistance to clarithromycin in Korea. We analyzed the eradication rates and the 10-year change in the eradication rates in Korea. Methods: PubMed, EMBASE, the Cochrane Library, and KoreaMed were searched for studies published between January 2007 and June 2018. The pooled eradication rates and their 95% CIs were estimated using a random-effect logistic regression model. Results: Twenty-six randomized controlled studies on standard triple therapy conducted in Korea were selected. The intention-to-treat (ITT) and per protocol analyses showed pooled eradication rates of standard triple therapy of 71.6% (95% CI, 69.9~73.3%) and 79.6% (95% CI, 76.6~82.2%), respectively. The eradication rate decreased with time. The ITT analysis showed that the 14-day therapy (78.1% [95% CI, 75.2~80.7%]) had significantly higher eradication rates than the 7-day therapy (70.0% [95% CI, 68.5~71.4%]) (P<0.01). Conclusions These results suggest that the eradication rate of standard triple therapy, as the first-line therapy, has shown an unacceptable decrease. The eradication rate increased when the duration of therapy was increased to 14 days, but it was not satisfactory. Therefore, other treatment regimens or therapies based on susceptibility tests should be considered for the first-line therapy.

Background/Aims: The eradication rate of the first-line standard triple therapy (STT) for Helicobacter pylori (H. pylori) infection has decreased since 2000; therefore, other first-line therapies are required. This study was aimed at investigating the efficacy of bismuth-containing quadruple therapy (PBMT) for first-line H. pylori eradication compared to STT, sequential therapy (SQT), and concomitant therapy (CT). Materials and Methods: The Ovid-MEDLINE, Koreamed, EMBASE, KMBASE, and Cochrane Library databases were searched from January 2008 to July 2018. All identified randomized controlled trials (RCTs) comparing PBMT and non-PBMT for first-line H. pylori eradication therapy were included in the final analysis. Results: A total of 3,653 patients from seven RCTs were enrolled. The pooled eradication rates of PBMT by intention-to-treat (ITT) and per-protocol (PP) analyses were 82.1% (95% CI, 68.2~90.8%) and 88.8% (95% CI, 77.1~94.9%), respectively. However, no statistically significant difference was observed in eradication rates of the 10- or 14-day PBMT as compared to 14-day STT, 10-day SQT, and 10-day CT in ITT and PP analyses. PBMT was significantly higher in adverse events than in the other eradication regimens (RR, 1.64; 95% CI, 1.11~2.44). Considerable heterogeneity in adverse events was observed among studies (χ2=88.7; P<0.001, I2=93%). Conclusions PBMT can be the first-line treatment for H. pylori eradication in Korea when other first-line options, including STT, SQT, or CT, are unavailable due to their high adverse event rates.

Background/Aims: As antibiotic resistance increases and new first-line therapies emerge, salvage therapies for Helicobacter pylori (H. pylori) eradication failures are becoming more common and complicated. This study aimed to systematically review overall salvage regimens after previous failure of H. pylori eradication. Materials and Methods: A systematic review of randomized clinical trials evaluating salvage therapies after previous H. pylori eradication failure was performed. A meta-analysis was conducted when an adequate number of studies suitable for grouping was found. Results: Overall, 36 studies with 77 treatment arms were identified, and they were highly heterogeneous regarding previously failed regimens and salvage regimens under comparison. Bismuth quadruple therapy after failure of standard triple therapy showed a pooled intention-to-treat (ITT) eradication rate of 75.5% (95% CI, 71.6~79.1%), and the rates were significantly higher with 14-day therapy than 7-day therapy by 9% (95% CI, 2~15%). Levofloxacin triple therapy after failure of standard triple therapy demonstrated a pooled ITT eradication rate of 73.3% (95% CI, 68.4~77.3%). In direct comparison, the two regimens were not significantly different in eradication rates. No study evaluated salvage regimens after the failure of bismuth or non-bismuth quadruple therapy. Conclusions The current studies regarding salvage regimens are highly heterogeneous. Bismuth quadruple therapy and levofloxacin triple therapy may be a reliable option after failure of standard triple therapy, but the regional profile of antibiotic resistance should be considered. Further studies are needed for salvage regimens after failure of non-bismuth or bismuth quadruple therapy.