Pragmatic nationwide master observational trial based on genomic alterations in advanced solid tumors: KOrean Precision Medicine Networking Group Study of MOlecular profiling guided therapy based on genomic alterations in advanced Solid tumors (KOSMOS)-II study protocol KCSG AL-22-09.

BACKGROUND: Next-generation sequencing (NGS) has been introduced to many Korean institutions to support molecular diagnostics in cancer since 2017, when it became eligible for reimbursement by the National Health Insurance Service. However, the uptake of molecularly guided treatment (MGT) based on NGS results has been limited because of stringent regulations regarding prescriptions outside of approved indications, a lack of clinical trial opportunities, and limited access to molecular tumor boards (MTB) at most institutions. The KOSMOS-II study was designed to demonstrate the feasibility and effectiveness of MGT, informed by MTBs, using a nationwide precision medicine platform. METHODS: The KOSMOS-II trial is a large-scale nationwide master observational study. It involves a framework for screening patients with metastatic solid tumors for actionable genetic alterations based on local NGS testing. It recommends MGT through a remote and centralized MTB meeting held biweekly. MGT can include one of the following options: Tier 1, the therapeutic use of investigational drugs targeting genetic alterations such as ALK, EGFR, ERBB2, BRAF, FH, ROS1, and RET, or those with high tumor mutational burden; Tier 2, comprising drugs with approved indications or those permitted for treatment outside of the indications approved by the Health Insurance Review and Assessment Service of Korea; Tier 3, involving clinical trials matching the genetic alterations recommended by the MTB. Given the anticipated proportion of patients receiving MGT in the range of 50% ± 3.25%, this study aims to enroll 1,000 patients. Patients must have progressed to one or more lines of therapy and undergone NGS before enrollment. DISCUSSION: This pragmatic master protocol provides a mass-screening platform for rare genetic alterations and high-quality real-world data. Collateral clinical trials, translational studies, and clinico-genomic databases will contribute to generating evidence for drug repositioning and the development of new biomarkers. TRIAL REGISTRATION: NCT05525858.

Cancer screening programs in South-east Asia and Western Pacific.

BACKGROUND: The burden of cancer can be altered by screening. The field of cancer screening is constantly evolving; from the initiation of program for new cancer types as well as exploring innovative screening strategies (e.g. new screening tests). The aim of this study was to perform a landscape analysis of existing cancer screening programs in South-East Asia and the Western Pacific. METHODS: We conducted an overview of cancer screening in the region with the goal of summarizing current designs of cancer screening programs. First, a selective narrative literature review was used as an exploration to identify countries with organized screening programs. Second, representatives of each country with an organized program were approached and asked to provide relevant information on the organizations of their national or regional cancer screening program. RESULTS: There was wide variation in the screening strategies offered in the considered region with only eight programs identified as having an organized design. The majority of these programs did not meet all the essential criteria for being organized screening. The greatest variation was observed in the starting and stopping ages. CONCLUSIONS: Essential criteria of organized screening are missed. Improving organization is crucial to ensure that the beneficial effects of screening are achieved in the long-term. It is strongly recommended to consider a regional cancer screening network.

Cost-Utility Analysis for Colorectal Cancer Screening According to the Initiating Age of National Cancer Screening Program in Korea.

BACKGROUND: This study aimed to identify the most cost-effective strategy for colorectal cancer screening using the fecal immunochemical test (FIT), focusing on screening initiation age in Korea. METHODS: We designed Markov simulation models targeting individuals aged 40 years or older. Twelve strategies combining screening initiation ages (40, 45, or 50 years old), termination ages (80 or no limit), and intervals (1 or 2 years) were modeled, and the most cost-effective strategy was selected. The robustness of the results was confirmed using one-way and probabilistic sensitivity analyses. Furthermore, the cost-effectiveness of the qualitative and quantitative FIT methods was verified using scenario analysis. RESULTS: The 2-year interval strategy with a screening age range of 45-80 years was the most cost-effective (incremental cost-utility ratio = KRW 7,281,646/quality adjusted life years). The most sensitive variables in the results were transition rate from advanced adenoma to local cancer and discount rate. The uncertainty in the model was substantially low. Moreover, strategies starting at the age of 40 years were also cost-effective but considered suboptimal. The scenario analysis showed that there was no significant difference in cost-effectiveness between strategies with various relative screening ratio of quantitative and qualitative method. CONCLUSION: The screening method for advancing the initiation age, as presented in the 2015 revised national screening recommendations, was superior regarding cost-effectiveness. This study provides a new paradigm for the development of a national cancer screening system in Korea, which can be utilized as a scientific basis for economic evaluations.

Risk of upper gastrointestinal cancer and death in persons with negative screening results: results from the National Cancer Screening Program in South Korea.

BACKGROUND: The Korea National Cancer Screening Program (KNCSP) offers upper endoscopy or upper gastrointestinal series (UGIS) biannually for people aged ≥ 40 years. This study aimed to assess the effect of negative screening results on the incidence of and mortality from upper gastrointestinal (GI) cancer. METHODS: A population-based retrospective cohort of 15,850,288 men and women was constructed using data from 3 national databases. The participants were followed until the end of 2017 for data on cancer incidence and in 2019 for data on the vital status. Cox proportional hazard model with time-varying exposure was used to assess the association. RESULTS: By the end of the follow-up period, 230,783 upper GI cancer cases and 99,348 upper GI cancer deaths were recorded. Negative gastric cancer screening was significantly associated with a lower risk of upper GI cancer in both UGIS (adjusted hazard ratio [aHR] = 0.81, 95% CI = 0.80-0.82) and upper endoscopy (aHR = 0.67, 95% CI = 0.67-0.68) groups. The HRs for upper GI mortality were 0.55 (95% CI = 0.54-0.56) and 0.21 (95% CI = 0.21-0.22) for the UGIS and upper endoscopy groups, respectively. The most significant reductions in the risk of upper GI cancer (UGIS: aHR = 0.76, 95% CI = 0.74-0.77; upper endoscopy: aHR = 0.60, 95% CI = 0.59-0.61) and death (UGIS: aHR = 0.54, 95% CI = 0.52-0.55; upper endoscopy: aHR = 0.19, 95% CI = 0.19-0.20) were observed among individual aged 60-69 years. CONCLUSION: Negative screening cases, especially in upper endoscopy of the KNCSP, were associated with an overall reduction in the risk of and mortality from upper GI cancer.

Effect of colorectal cancer screening on long-term survival of colorectal cancer patients: Results of the Korea National Cancer Screening Program.

The Korea National Cancer Screening Program (KNCSP) provides fecal immunochemical test-based colorectal cancer (CRC) screening for people aged ≥50 years. Our study aimed to investigate the long-term survival effects of CRC screening based on screening history and interval time since screening. The study cohort was obtained by linking three national databases, namely the Korea Central Cancer Registry, KNCSP database and Death Certificate. We included 32 509 CRC patients diagnosed in 2008 to 2009, who underwent CRC screening via the KNCSP between 2004 and 2009. The patients were followed-up until 2019, and their survival was assessed according to their CRC screening history. Cox proportional hazards regression was used to compare time to deaths among CRC patients according to CRC screening history, after adjusting for covariates. Of the 32 509 patients, 20 022 (61.5%) patients were alive by the end of 2019. Long-term survival was significantly higher among screened patients (68.2%) than nonscreened (57.2%) individuals. Compared to never-screened patients, the hazard ratio (HR) for CRC-specific death in screened patients was 0.77 (95% CI%, 0.73-0.80). Lowest HR was observed in screened, localized CRC patients (HR, 0.48; 95% CI, 0.42-0.56); HR for CRC-specific death was the lowest in patients screened within 12 months of diagnosis (HR, 0.70; 95% CI, 0.66-0.74), following which, the HRs increased with increasing time interval. CRC screening was positively associated with favorable prognosis in CRC patients aged 50 to 79 years. The effects on long-term survival according to interval time was the best among individuals screened within 1 year before diagnosis.

Disparities in Liver Cancer Surveillance Among People With Disabilities: A National Database Study in Korea.

GOAL: The goal of this study was to determine disparities in liver cancer surveillance among people with disabilities is the goal of this study. BACKGROUND: Using the linked administrative database in Korea, we sought to investigate (1) whether there are disparities in liver cancer surveillance according to degree and type of disability and (2) temporal trends in liver cancer surveillance among people with disabilities. MATERIALS AND METHODS: We linked national disability registration data with national cancer surveillance data. We analyzed age-standardized participation rates for each year during the 2006-2015 period according to presence, type, and severity of the disability. We also examined factors associated with liver cancer surveillance by multivariate logistic regression using the most current data (2014-2015). RESULTS: The age-adjusted and sex-adjusted surveillance rate for liver cancer in people with disabilities increased from 25.7% in 2006 to 49.6% in 2015; however, during the same period, surveillance rate among people without disabilities increased from 24.9% to 54.5%. As a result, disparities in surveillance for liver cancer increased over time. The surveillance participation rate among people with disabilities was 12% lower than among people without disabilities. Surveillance rates were markedly lower among people with severe disabilities [adjusted odds ratio (aOR)=0.71] and people with renal disease (aOR=0.43), brain injuries (aOR=0.60), ostomy problems (aOR=0.60), and intellectual disabilities (aOR=0.69). CONCLUSIONS: Despite the availability of a national liver cancer surveillance program, a marked disparity was found in liver cancer surveillance participation, especially among people with severe disabilities, renal disease, or brain-related or mental disabilities.

Korean colonoscopy screening pilot study (K-cospi) for screening colorectal cancer: study protocol for the multicenter, community-based clinical trial.

BACKGROUND: The Korean National Cancer Screening Program has been providing annual fecal immunochemical test for colorectal cancer (CRC) to adults aged 50 years and older since 2004. The Korean Colonoscopy Screening Pilot Study was developed to evaluate the effectiveness of colonoscopy screening for CRC incidence and mortality, screening-related complications, and acceptability of colonoscopy as a primary modality for the national CRC screening program. METHODS: This study and its protocols have been approved by the Korean Public Institutional Review Board and the National Cancer Center Institutional Review Board. We obtain written informed consent from all participants. The target population is males and females aged 50-74 years living within the pilot sites. A total of 26,640 participants will be recruited for colonoscopy screening. Subjects who have been diagnosed with CRC, who are currently undergoing treatment for CRC, or who have undergone colonoscopy screening within the past 5 years are not allowed to participate. All participants need to complete baseline questionnaires. This pilot study is currently conducted by 104 endoscopists from 57 national cancer screening institutions (42 primary, 10 secondary, and 5 tertiary institutions) located in Goyang-si, Gimpo-si, and Paju-si. The number of endoscopists, medical institutions, and districts participating in the pilot study will be expanded, if necessary. Participating endoscopists at each medical institution perform colonoscopy and report the colonoscopy results to a centralized electronic case report system. We conduct a telephone survey after 7 days and 4 weeks post-colonoscopy to assess for procedure-related complications and satisfaction of the participants. In case of abnormal findings from colonoscopy screening, we track the results from follow-up diagnostic tests. Data from this pilot study will be linked to the diagnostic workup results, the Korean Cancer Registry, and death certificate data for analysis of the performance, long-term effects, and cost-effectiveness of colonoscopy. DISCUSSION: The results will provide critical information to determine whether the introduction of colonoscopy as the primary modality of the Korean National Cancer Screening Program would be acceptable and feasible. Trial registration Korean Clinical Research Information Service registry, KCT0004142. Registered on 15 July 2019, http://cris.nih.go.kr/cris/en/search/search_result_st01.jsp?seq=16227.

Effect of Digital Mammography for Breast Cancer Screening: A Comparative Study of More than 8 Million Korean Women.

Background Full-field digital mammography (FFDM) has been accepted as a superior modality for breast cancer screening compared with conventional screen-film mammography (SFM), especially in women younger than 50 years or with dense breasts. Purpose To evaluate the accuracy of FFDM for breast cancer screening. Materials and Methods Data from January 1, 2011 to December 31, 2013 in the database from a nationwide breast cancer screening program linked with the national cancer registry were retrospectively analyzed. The study included Korean women aged 40-79 years who had undergone screening mammography with SFM, computed radiography (CR), or FFDM. The sensitivity, specificity, positive predictive value (PPV), and absolute and relative differences among these modalities were calculated, followed by pairwise comparison tests with multiple testing corrections. The areas under the receiver operating characteristic curve (AUCs) were also estimated and compared by using the DeLong method with Bonferroni correction. Results Among the 8 482 803 women included (mean age, 55 years ± 10), 34.4% (2 920 279 of 8 482 803), 51.7% (4 385 807 of 8 482 803), and 13.9% (1 176 717 of 8 482 803) underwent SFM, CR, and FFDM, respectively. The sensitivity and PPV were higher for FFDM than for SFM (adjusted odds ratio, 1.77 [95% confidence interval {CI}: 1.62, 1.95] for sensitivity and 1.36 [95% CI: 1.29, 1.43] for PPV) and CR (adjusted odds ratio, 1.70 [95% CI: 1.56, 1.85] for sensitivity and 1.26 [95% CI: 1.20, 1.32] for PPV), whereas specificity was lower with FFDM. The overall AUC for FFDM was 0.80 (95% CI: 0.80, 0.81), which was higher than that for SFM (0.75 [95% CI: 0.75, 0.76]) and CR (0.76 [95% CI: 0.75, 0.76]). P < .05 was found for differences in sensitivity, PPV, and AUC among modalities overall and in most of the subgroups of age, breast density, and screening round. Conclusion Full-field digital mammography allows better discrimination or prediction of breast cancer in the general female population than screen-film mammography or computed radiography, regardless of age, breast density, or screening round. © RSNA, 2019 Online supplemental material is available for this article.

Use of Gadoxetic Acid-enhanced Liver MRI and Mortality in More than 30 000 Patients with Hepatocellular Carcinoma: A Nationwide Analysis.

Background The impact on survival of gadoxetic acid-enhanced MRI in addition to multiphase contrast material-enhanced CT for initial staging in patients with hepatocellular carcinoma (HCC) is unknown. Purpose To compare all-cause mortality in patients with HCC who underwent CT only, CT plus non-gadoxetic acid-enhanced MRI, or CT plus gadoxetic acid-enhanced MRI as part of their initial diagnostic work-up. Materials and Methods The authors performed a nationwide retrospective cohort study of patients diagnosed with HCC in South Korea between January 2008 and December 2010. Follow-up extended through December 2014. The primary outcome was all-cause mortality. Cox proportional hazards regression model with adjustment of confounding factors was used to estimate hazard ratios (HRs) for all-cause mortality. Results Among 30 023 patients with HCC (mean age ± standard deviation, 58.5 years ± 10.7, 23 978 men), the proportions of patients in whom HCC was diagnosed using CT only, CT plus non-gadoxetic acid-enhanced MRI, and CT plus gadoxetic acid-enhanced MRI were 56.1%, 12.9%, and 31.0%, respectively. In adjusted analysis using CT only as the reference category, the HR for mortality for CT plus gadoxetic acid-enhanced MRI was 0.64 (95% confidence interval [CI]: 0.62, 0.67; P < .001), and the HR for CT plus non-gadoxetic acid-enhanced MRI was 0.71 (95% CI: 0.68, 0.75; P < .001). Use of CT plus gadoxetic acid-enhanced MRI was associated with lower mortality compared with CT plus non-gadoxetic acid-enhanced MRI (adjusted HR, 0.90; 95% CI: 0.85, 0.95; P < .001), but this survival advantage was restricted to patients with localized disease. Conclusion In patients with hepatocellular carcinoma, additional use of contrast-enhanced MRI was associated with lower mortality. Furthermore, CT plus gadoxetic acid-enhanced MRI was associated with better survival than CT plus non-gadoxetic acid-enhanced MRI but only in patients with localized disease. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Kim in this issue.

Disparities in gastric cancer screening among people with disabilities: a national registry-linkage study in South Korea.

BACKGROUND AND AIM: Using the national disability registration linked to the cancer screening database in Korea, we examined (1) trends in the gastric cancer screening rate among people with disabilities over time, and (2) whether gastric cancer screening participation and modalities differed according to presence, severity, and type of disability. METHODS: We examined gastric cancer screening participation rates among individuals with registered disability, from 2006 to 2015. RESULTS: The age- and sex-adjusted rate for gastric cancer screening in people with disabilities increased from 25.9% in 2006 to 51.9% in 2015 (change: + 26.0%). During the same period, screening rates among people without disability improved from 24.7 to 56.5% (change: + 31.8%). Disability was associated with a screening rate [adjusted odds ratio (aOR) 0.89, 95% confidence interval (CI), 0.88-0.89]. Screening rates were markedly lower among people with severe disabilities (aOR 0.58, 95% CI 0.57-0.58) and people with autism (aOR 0.36, 95% CI 0.25-0.52), renal failure (aOR 0.39, 95% CI 0.38-0.39), brain injury (aOR 0.41, 95% CI 0.40-0.41), ostomy problems (aOR 0.53, 95% CI 0.51-0.55), intellectual disabilities (aOR 0.54, 95% CI 0.53-0.54), or mental disorders (aOR 0.55, 95% CI 0.54-0.56). The use of gastroscopy as the initial screening modality in people with disabilities was lower than in people without a disability. CONCLUSIONS: In spite of the availability of national gastric cancer screening program, we found significant disparities in gastric cancer screening participation, especially among people with severe disabilities and those with renal failure or brain-related/mental disabilities.

Limitations of Deep Learning Attention Mechanisms in Clinical Research: Empirical Case Study Based on the Korean Diabetic Disease Setting.

BACKGROUND: Despite excellent prediction performance, noninterpretability has undermined the value of applying deep-learning algorithms in clinical practice. To overcome this limitation, attention mechanism has been introduced to clinical research as an explanatory modeling method. However, potential limitations of using this attractive method have not been clarified to clinical researchers. Furthermore, there has been a lack of introductory information explaining attention mechanisms to clinical researchers. OBJECTIVE: The aim of this study was to introduce the basic concepts and design approaches of attention mechanisms. In addition, we aimed to empirically assess the potential limitations of current attention mechanisms in terms of prediction and interpretability performance. METHODS: First, the basic concepts and several key considerations regarding attention mechanisms were identified. Second, four approaches to attention mechanisms were suggested according to a two-dimensional framework based on the degrees of freedom and uncertainty awareness. Third, the prediction performance, probability reliability, concentration of variable importance, consistency of attention results, and generalizability of attention results to conventional statistics were assessed in the diabetic classification modeling setting. Fourth, the potential limitations of attention mechanisms were considered. RESULTS: Prediction performance was very high for all models. Probability reliability was high in models with uncertainty awareness. Variable importance was concentrated in several variables when uncertainty awareness was not considered. The consistency of attention results was high when uncertainty awareness was considered. The generalizability of attention results to conventional statistics was poor regardless of the modeling approach. CONCLUSIONS: The attention mechanism is an attractive technique with potential to be very promising in the future. However, it may not yet be desirable to rely on this method to assess variable importance in clinical settings. Therefore, along with theoretical studies enhancing attention mechanisms, more empirical studies investigating potential limitations should be encouraged.

Effectiveness of the Korean National Cancer Screening Program in Reducing Gastric Cancer Mortality.

BACKGROUND & AIMS: It is not clear whether screening for gastric cancer by upper endoscopy or upper gastrointestinal (UGI) series examinations (looking at the upper and middle sections of the gastrointestinal tract by imaging techniques) reduces mortality. Nevertheless, the Korean National Cancer Screening Program for gastric cancer was launched in 1999 to screen individuals 40 years and older for gastric cancer using these techniques. We evaluated the effectiveness of these techniques in gastric cancer detection and compared their effects on mortality in the Korean population. METHODS: We performed a nested case-control study using data from the Korean National Cancer Screening Program for gastric cancer since 2002. A total of 16,584,283 Korean men and women, aged 40 years and older, comprised the cancer-free cohort. Case subjects (n = 54,418) were defined as individuals newly diagnosed with gastric cancer from January 2004 through December 2009 and who died before December 2012. Cases were matched with controls (subjects who were alive on the date of death of the corresponding case subject, n = 217,672) for year of entry into the study cohort, age, sex, and socioeconomic status. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained via conditional logistic regression analysis. RESULTS: Compared with subjects who had never been screened, the overall OR for dying from gastric cancer among ever-screened subjects was 0.79 (95% CI, 0.77-0.81). According to screening modality, the ORs of death from gastric cancer were 0.53 (95% CI, 0.51-0.56) for upper endoscopy and 0.98 (95% CI, 0.95-1.01) for UGI series. As the number of endoscopic screening tests performed per subject increased, the ORs of death from gastric cancer decreased: 0.60 (95% CI, 0.57-0.63), 0.32 (95% CI, 0.28-0.37), and 0.19 (95% CI, 0.14-0.26) for once, twice, and 3 or more times, respectively. CONCLUSIONS: Within the Korean National Cancer Screening Program, patients who received an upper endoscopy were less likely to die from gastric cancer; no associations were found for UGI series.

Risk of Interval Cancer in Fecal Immunochemical Test Screening Significantly Higher During the Summer Months: Results from the National Cancer Screening Program in Korea.

OBJECTIVES: This study aimed to evaluate the impact of seasonal variations in climate on the performance of the fecal immunochemical test (FIT) in screening for colorectal cancer in the National Cancer Screening Program in Korea. METHODS: Data were extracted from the National Cancer Screening Program databases for participants who underwent FIT between 2009 and 2010. We compared positivity rates, cancer detection rates, interval cancer rates, positive predictive value, sensitivity, and specificity for FIT during the spring, summer, fall, and winter seasons in Korea. RESULTS: In total, 4,788,104 FIT results were analyzed. FIT positivity rate was lowest during the summer months. In the summer, the positive predictive value of FIT was about 1.1 times (adjusted odds ratio (aOR) 1.08, 95% confidence interval (CI) 1.00-1.16) higher in the overall FIT group and about 1.3 times (aOR 1.29, 95% CI 1.10-1.50) higher in the quantitative FIT group, compared to those in the other seasons. Cancer detection rates, however, were similar regardless of season. Interval cancer risk was significantly higher in the summer for both the overall FIT group (aOR 1.16, 95% CI 1.07-1.27) and the quantitative FIT group (aOR 1.31, 95% CI 1.12-1.52). In addition, interval cancers in the rectum and distal colon were more frequently detected in the summer and autumn than in the winter. CONCLUSIONS: The positivity rate of FIT was lower in the summer, and the performance of the FIT screening program was influenced by seasonal variations in Korea. These results suggest that more efforts to reduce interval cancer during the summer are needed in population-based screening programs using FIT, particularly in countries with high ambient temperatures.

Comparison of cervical cancer screening among women with and without hysterectomies: a nationwide population-based study in Korea.

BACKGROUND: Cervical cancer screening is not recommended for women who underwent hysterectomy with no history of cervical intraepithelial neoplasia (CIN) of grade 2 or higher. We aimed to determine the cervical cancer screening rate in Korean women who underwent hysterectomies and compare it to that in women with intact uteri. METHODS: We used data from the 2014-2016 Korean National Cancer Screening Survey; 6807 women aged 30-74 years were included in the study. Participants were asked about their experiences with cervical cancer screening, hysterectomy status, and other variables associated with cancer screening. RESULTS: The screening rates among women who have undergone a hysterectomy vs. those who have not during the past 2 years were 61.8% (95% confidence interval [CI], 58.8-64.9) and 64.7% (95% CI, 64.1-65.3), respectively. Among younger women (30-44 years) and women with a family history of cancer, those with hysterectomies showed a higher cervical cancer screening rate than those without (77.8% vs. 57.1% and 75.0% vs. 67.1%, respectively). CONCLUSIONS: Despite available evidence and clinical recommendations, a considerable number of Korean women who no longer have a cervix continue to undergo unnecessary cervical cancer screening. It is necessary to identify the exact underlying causes for this phenomenon, and systematic efforts are required to prevent unnecessary screening for women who have undergone a hysterectomy.

Higher satisfaction with an alternative collection device for stool sampling in colorectal cancer screening with fecal immunochemical test: a cross-sectional study.

BACKGROUND: Identifying preferences for stool collection devices may help increase uptake rates for colorectal cancer screening via fecal immunochemical test (FIT). This study surveyed satisfaction with different devices utilized to collect stool samples for FIT: a conventional container and a sampling bottle (Eiken OC-Sensor). METHODS: This cross-sectional study was conducted at the National Cancer Center, Korea. Participants aged 50-74 years who used either a conventional container or a sampling bottle to collect a stool sample for FIT were asked to complete a questionnaire designed to survey their satisfaction with the stool collection process and their intentions to undergo FIT in subsequent screening rounds. In total, 1657 participants (1224 conventional container, 433 sampling bottle) were included for analysis. RESULTS: Satisfaction with the sampling bottle was higher than that with the conventional container (79.9% vs.73.0%, p = 0.005, respectively; aOR = 1.52, 95% CI: 1.16-2.00). Participants satisfied with the sampling bottle were more likely to be female, be of younger age (50-64 years old), have higher household income, and have prior experience with FIT. Intentions to undergo subsequent screening were stronger among those given the sampling bottle than those given the conventional container (aOR = 1.78, 95% CI: 1.28-2 .48). CONCLUSIONS: Satisfaction with the stool collection process was higher with the sampling bottle. However, additional studies are needed to validate whether the increased satisfaction and stronger intentions to undergo subsequent screening with the sampling bottle could actually lead to increased uptake in subsequent rounds, along with analysis of the device's cost effectiveness.

Perceptions of colorectal cancer screening and recommendation behaviors among physicians in Korea.

BACKGROUND: Physician recommendations for colorectal cancer (CRC) screening have consistently been shown to be a strong predictor of screening. The aim of this study was to investigate perceptions of CRC screening modalities and recommendation behaviors among physicians in Korea. METHODS: A cross-sectional, nationally representative survey conducted between November 2013 and February 2014. In total, 379 physicians (241 primary care physicians and 138 physicians affiliated with the Korean Association for the Study of Intestinal Diseases responded to this survey (overall response rate of 31.4%). RESULTS: About 29% of all respondents "always" recommended and about 67% "sometimes" recommended CRC screening. Colonoscopy was perceived as an effective primary screening tool for CRC, and 80% of the physicians recommended colonoscopy for CRC screening. Only 7% recommended FOBT. In multivariate analysis, recommending FOBT was associated with stronger belief in the screening efficacy of FOBT (aOR 3.70, 95% CI 2.09, 6.57), weaker belief in the screening efficacy of colonoscopy (aOR 0.29, 95% CI 0.12, 0.69), and negative decisional balance for colonoscopy screening (aOR 0.82, 95% CI 0.71, 0.95). CONCLUSIONS: Although FOBT is provided free-of-charge through a nationwide CRC screening program, colonoscopy was more commonly recommended and preferred by physicians.

The Korean Study of Women's Health-Related Issues (K-Stori): Rationale and Study Design.

BACKGROUND: Measures to address gender-specific health issues are essential due to fundamental, biological differences between the sexes. Studies have increasingly stressed the importance of customizing approaches directed at women's health issues according to stages in the female life cycle. In Korea, however, gender-specific studies on issues affecting Korean women in relation to stages in their life cycle are lacking. Accordingly, the Korean Study of Women's Health-Related Issues (K-Stori) was designed to investigate life cycle-specific health issues among women, covering health status, awareness, and risk perceptions. METHODS: K-Stori was conducted as a nationwide cross-sectional survey targeting Korean women aged 14-79 years. Per each stage in the female life cycle (adolescence, childbearing age, pregnancy & postpartum, menopause, and older adult stage), 3000 women (total 15,000) were recruited by stratified multistage random sampling for geographic area based on the 2010 Resident Registration Population in Korea. Specialized questionnaires per each stage (total of five) were developed in consultation with multidisciplinary experts and by reflecting upon current interests into health among the general population of women in Korea. This survey was conducted from April 1 to June 31, 2016, at which time investigators from a professional research agency went door-to-door to recruit residents and conducted in-person interviews. DISCUSSION: The study's findings may help with elucidating health issues and unmet needs specific to each stage in the life cycle of Korean women that have yet to be identified in present surveys.

A qualitative study of women's views on overdiagnosis and screening for thyroid cancer in Korea.

BACKGROUND: The incidence of thyroid cancer in Korea has increased by about 25 % every year for the past 10 years. This increase is largely due to a rising incidence in papillary thyroid cancer, which is associated with an overdiagnosis of small tumors that may never become clinically significant. This study was conducted to explore Korean women's understanding of overdiagnosis and to investigate changes in screening intention in response to overdiagnosis information. METHODS: Focus group interviews were conducted among women of ages 30-69 years, who are commonly targeted in Korea for cancer screening. Women were divided into four groups according to thyroid cancer screening history and history of thyroid disease. Of 51 women who were contacted, 29 (57 %) participated in the interviews. RESULTS: Prior awareness of thyroid cancer overdiagnosis was minimal. When informed about the risks of overdiagnosis, the participants were often surprised. Overcoming initial malcontent, many women remained skeptic about overdiagnosis and trusted in the advice of their physicians. Meanwhile, some of the study participants found explanations of overdiagnosis difficult to understand. Further, hearing about the risks of overdiagnosis had limited impact on the participants' attitudes and intentions to undergo thyroid cancer screening, as many women expressed willingness to undergoing continued screening in the future. CONCLUSION: A large majority of Korean women eligible for and had undergone thyroid cancer screening were unaware of the potential for overdiagnosis. Nevertheless, overdiagnosis information generally had little impact on their beliefs about thyroid cancer screening and their intentions to undergo future screening. Further research is needed to determine whether these findings could be generalized to the wider Korean population.

Different socioeconomic inequalities exist in terms of the prevention, diagnosis and control of diabetes.

OBJECTIVE: To evaluate socioeconomic disadvantage in prevalence, awareness and control of diabetes in universal coverage healthcare system. METHODS: Data from the fifth KNHNES (2010-12) were analyzed. The sample included 10,208 individuals with diabetes aged ≥30 years. Diabetes was defined by (i) a self-reported previous diagnosis of diabetes made by a physician, (ii) the current use of oral hypoglycaemic agents and/or insulin or (iii) fasting plasma glucose ≥126 mg/dl. Subjects who were first diagnosed by the survey were classified as 'undiagnosed'. Inadequate control was defined as HbA1c ≥6.5%. RESULTS: It was estimated that 26.4% of subjects with diabetes were not aware of their condition and 73.1% of cases of diabetes were not adequately controlled. Inequalities in socioeconomic status were related to the diabetes prevalence in both men and women. Educational level was not predictive of diagnosis or control in men or women, whereas lower household income level was associated with diagnosis in men only. CONCLUSIONS: This widespread lack of awareness and inadequate control underscore the need for intensive efforts in these domains. Monitoring is expected to highlight the gaps in the preventive and care services offered to the most vulnerable individuals and it may induce governments and practitioners to address these issues.

Socioeconomic inequality in health-related quality of life among Korean adults with chronic disease: an analysis of the Korean Community Health Survey.

OBJECTIVES: Health-related quality of life is crucial for people dealing with chronic illness. This study investigated the quality of life in individuals with 5 common chronic conditions in Korea. We also analyzed socioeconomic factors such as education, income, occupation, and urbanization to identify determinants of inequality. METHODS: Using 2016 Korea Community Health Survey data, we examined individuals aged 30 or older with chronic diseases (diabetes, hypertension, cardiovascular disease, hyperlipidemia, arthritis) using the EuroQol 5-Dimension 3 Level tool. We analyzed the associations between socioeconomic factors (education, income, occupation, urbanization) and quality of life using descriptive statistics and regression analysis. Inequality indices (relative inequality index, absolute inequality index) were used to measure inequality in quality of life. RESULTS: Individuals with higher income levels showed a 1.95-fold higher likelihood of a better quality of life than those with the lowest income. The lowest income group had higher odds of mobility (adjusted odds ratio [aOR], 2.2), self-care (aOR, 2.1), activity limitations (aOR, 2.4), pain/discomfort (aOR, 1.8), and anxiety/depression (aOR, 2.3). Educational disparities included a 3-fold increase in mobility and daily activity problems for those with elementary or lower education. Well-educated participants had a 1.94 times higher quality of life, with smaller differences in anxiety/depression and self-management. The income gap accounted for 14.1% of variance in quality-of-life disparities. CONCLUSIONS: Addressing socioeconomic disparities in the quality of life for individuals with chronic diseases necessitates tailored interventions and targeted health policies. This research informs policymakers in developing focused initiatives to alleviate health inequities. It emphasizes the importance of mental health support and ensuring affordable, accessible healthcare services.