The Relationship of Nurse and Physician Staffing in Intensive Care Units with Patient Outcomes in Postoperative Patients on Ventilators: An Analysis Using Korean National Health Insurance Data.

This study examined the associations of nurse and physician staffing in intensive care units (ICUs) with hospital-acquired pneumonia (HAP) incidence and in-hospital mortality in postoperative patients on ventilators. National Health Insurance claims data and death statistics were used to investigate the nurse staffing level and the presence or absence of a dedicated resident and specialist in each ICU. The participants were patients aged 20-85 who underwent any of 13 surgical procedures and were placed on a ventilator in the ICU after the procedure. Of 11,693 patients, 307 (2.6%) experienced HAP and 1280 (10.9%) died during hospitalization. Compared to hospitals with lower nurse-to-patient ratios, patients in hospitals with higher ratios had statistically significantly higher risks of HAP and in-hospital mortality. The presence of a dedicated resident in the ICU did not statistically significantly affect HAP incidence or in-hospital mortality. The presence of an ICU specialist was statistically significantly associated with in-hospital mortality but not HAP incidence. Our findings suggest that a higher level of nursing staff in the ICU is inversely associated with HAP incidence. The legal standards for nurse staffing in the ICU should be strengthened in order to improve the quality of care and patient safety.

Estimation of Utility Weights for Prostate-related Health States in Korea.

OBJECTIVES: Very limited previous research has investigated the utility weights of prostate-related diseases in the general population in Korea. The purpose of this study was to calculate the utility of prostate-related health states in the Korean general public using the standard gamble (SG) method. METHODS: Seven health states for hypothetical prostate cancers, 1 for benign prostate hyperplasia, and 1 for erectile dysfunction were developed based on patient education material and previous publications. In total, 460 responses from the Korean general population were used to analyze the utility of prostate-related health states. Computer-assisted personal interviews were conducted, and utility values were measured using a visual analogue scale (VAS) and SG. Mean utility values were calculated for each prostate-related health state. RESULTS: The mean utility values of prostate cancer derived from SG ranged from 0.281 (metastatic castration-refractory prostate cancer) to 0.779 (localized prostate cancer requiring prostatectomy). The utility value of benign prostate hyperplasia was 0.871, and that of erectile dysfunction was 0.812. The utility values obtained using the SG method in all conditions were higher than the values obtained by VAS. There were no significant demographic variables affecting utility values in multivariate analysis. CONCLUSIONS: Our findings might be useful for economic evaluation and utility calculation of screening and interventions for prostate-related conditions in the general population.

Cost Utility Analysis of a Pilot Study for the Korean Lung Cancer Screening Project.

PURPOSE: The aim of this study was to evaluate the cost utility of a pilot study of Korean Lung Cancer Screening Project. MATERIALS AND METHODS: We constructed a Markov model consisting of 26 states based on the natural history of lung cancer according to the Surveillance, Epidemiology, and End Results summary stage (localized, regional, distant). In the base case, people aged 55-74 years were under consideration for annual screening. Costs and quality-adjusted life years were simulated to calculate the incremental cost utility ratio. Sensitivity analyses were performed on the uncertainty associated with screening target ages, stage distribution, cost, utility, mortality, screening duration, and discount rate. RESULTS: The base case (US$25,383 per quality-adjusted life year gained) was cost-effective compared to the scenario of no screening and acceptable considering a willingness-to-pay threshold of US$27,000 per quality-adjusted life years gained. In terms of the target age of screening, the age between 60 and 74 years was the most cost-effective. Lung cancer screening was still cost-effective in the sensitivity analyses on the cost for treatment, utility, mortality, screening duration, and less than 5% discount rates, although the result was sensitive to a rise in positive rates or variation of stage distribution. CONCLUSION: Our results showed the cost-effectiveness of annual low-dose computed tomography screening for lung cancer in high-risk populations.

The impact of overactive bladder on health-related quality of life in Korea: based on the results of a Korean Community Health Survey.

PURPOSE: This study aimed to assess the impact of overactive bladder on health-related quality of life (HRQoL) in a community-based sample of Korean population. METHODS: The data of adults aged 19 and over that who participated in the 2012 Korean Community Health Survey were analyzed. Overactive bladder severity was classified as normal, mild, moderate, or severe using the Overactive Bladder Symptom scores, and HRQoL was evaluated using EQ-5D-3L. Relations between HRQoL and the severities and symptoms of OAB were investigated. Sampling weighted adjusted multiple regression analysis was performed to determine the effect of OAB symptom severity on HRQoL. RESULTS: Of the 226,867 study subjects, 12,303 (5.4%) had OAB, and 552 (0.2%) had an OABSS of ≥ 12, indicating severe OAB. The problem -reporting rate significantly increased in all EQ-5D-3L dimensions as OAB severity increased. After adjusting for other variables, OAB severity had a significant effect on EQ-5D-3L index. Urge incontinence had greatest impact on quality of life. CONCLUSIONS: As the severity of OAB increased from mild to severe, quality of life decreased significantly. OAB was found to negatively affect HRQoL.

Exploring health-related quality of life and frailty in older adults based on the Korean Frailty and Aging Cohort Study.

PURPOSE: The study aimed to analyze the association between frailty and health-related quality of life (HRQOL) based on the Korean Frailty and Aging Cohort Study. METHODS: In this cross-sectional study, 2905 adults aged 70 to 84 years were enrolled. Frailty was determined according to the Fried frailty index. HRQOL was measured using the 5-level EuroQol questionnaire (EQ-5D-5L) and the 12-item Short-Form Health Survey version 2 (SF-12). Hierarchical linear regressions were conducted to examine the relationship between frailty and HRQOL and a logistic regression analysis was performed to estimate odds ratios of frailty status in the scores of the lowest quartiles in each scale. RESULTS: Of the total respondents, 7.8% were frail, 47.0% were pre-frail, and 45.2% were robust. Frail respondents had significantly lower HRQOL scores than robust respondents, especially for EQ-5D-5L utility weights (0.74 vs 0.93). Frailty was strongly associated with decreased HRQOL in both physical and mental component summary of SF-12 (p < 0.001). Both pre-frail and frail states were related to greater odds of scoring in the bottom 25% of HRQOL scales compared to the non-frail state (p < 0.0001). CONCLUSION: Frailty was associated with declined HRQOL in Korean older adults. This result recommends raising awareness about identifying and preventing frailty for better quality of life in the Korean elderly population.

Estimation of population-based utility weights for health states of chronic kidney disease, dialysis and kidney transplantation.

AIM: This study aimed to determine the utility of chronic kidney disease (CKD)-related health states in the Korean general population by using the standard gamble (SG) method. METHODS: Seven hypothetical CKD-related health states were developed and revised based on previous publications. Data from 242 individuals from the Korean general population were obtained via computer-assisted personal interviews and used to evaluate the CKD-related health states by using the visual analogue scale (VAS) and SG methods. Mean and median utility values were calculated for each health state. To assess the reliability of the valuation, some samples were retested and evaluated using intraclass correlation coefficients (ICC). RESULTS: In all health states, the utility weights from SG were higher than those from VAS. The difference in utility values between the two valuation methods ranged from 0.258 to 0.308. The utility value of CKD grade 3 was the highest and that of peritoneal dialysis (PD) was the lowest. The utility weights tended to decrease in accordance with the progression of CKD. CKD grade 3 was assigned a SG utility value of 0.878, whereas PD was assigned 0.507. The SG utility values of predialysis end-stage renal disease, haemodialysis, kidney transplantation (KT), and post-KT recovery states were 0.666, 0.547, 0.748 and 0.827, respectively. The mean ICC (SD) at the individual level was 0.746 (0.281) for the SG scores. CONCLUSION: Our results could be used to measure the burden of kidney disease or to evaluate the economic efficiency of CKD-related interventions.

Health-related quality of life in adult males with lower urinary tract symptoms.

PURPOSE: To assess the status and impact of lower urinary tract symptoms (LUTS) on health-related quality of life (HRQoL) in a community-based sample of Korean adult males. METHODS: We analyzed the data of 101,606 adult males aged ≥ 19 years of age obtained during the 2011 Korean Community Health Survey. Subject data were assessed for LUTS and HRQoL using international prostate symptom scores, and EuroQol-five-dimensions three-level version (EQ-5D-3L) and EuroQol-visual analogue scale (EQ-VAS) scores. RESULTS: Of the 101,606 subjects, 53,323 (52.5%) reported having at least one LUTS and 3116 (3.1%) had an IPSS of ≥ 20, indicating severe LUTS. In those aged 19-39 years, 28.7% (8343/29,072) reported they had mild to severe LUTS. The prevalence of LUTS was high among those aged 40-59 years (47.7%), 60-79 years (80.5%), and ≥ 80 years (91.2%). In addition, EQ-5D-3L and EQ-VAS scores decreased as LUTS severity and frequency increased. CONCLUSIONS: Adult men of all ages with mild to severe LUTS have poorer health statuses and quality of life. Even among young males, LUTS severity and was found to negatively affect HRQoL.

Estimating Lifetime Duration of Diabetes by Age and Gender in the Korean Population Using a Markov Model.

BACKGROUND: Duration of type 2 diabetes is clinically important. Duration of morbidity is an independent and critical predictor of developing its complications. This study aims to explore an applicability of a Markov model to estimate the duration of diabetes in the Korean population. METHODS: We constructed the Markov model with two Markov states, diabetes and death, for estimation of duration of diabetes. The cycle of the Markov model was 1 year. Each diabetes onset by 5 years was considered from 30 to 85 years old or above. The endpoint of the Markov was 100 years old. Type 2 diabetes was operationally defined using the 10th revision of International Statistical Classification of Diseases and prescriptions of anti-diabetic drugs from the National Health Insurance Services-National Sample cohort. In each incident and existing prevalence cases, survival probabilities were obtained. Durations of diabetes from the Markov model were compared with those from the DisMod II program. Reductions of life expectancy due to diabetes were defined as differences of life expectancies between diabetic patients and the general public. Sensitivity analyses were also conducted using a cure rate and 95% confidence interval of survival probability. RESULTS: The duration of diabetes gradually decreased with incident age in both genders. In the early 30s, the duration was the largest at 48.9 and 41.9 years in women and men, respectively. In the average incident age group of type 2 diabetes, the late 50s, the reduction of life expectancy due to diabetes was estimated to be about two years in both genders. As annual cure probabilities increased, the durations of diabetes were reduced. CONCLUSION: This study estimated the duration of diabetes using a Markov model. The model seems to work well and diabetes could reduce life expectancy by about 2 years on average. This approach could be useful to estimate the duration of illness, calculate disability-adjusted life years, and conduct economic evaluation studies on interventions for diabetic patients.

A cross sectional survey on health-related quality of life among parents of children with allergic symptoms using the EQ-5D-5L.

Object: This study aims to evaluate the HRQOL of parents of children with allergic diseases using the EQ-5D-5L. Methods: The subjects of the study were parents of children enrolled in primary schools and daycare centers. The EQ-5D-5L was self-administered in the sample population, and demographic and health information of their children were collected. We assessed the difference in EQ-5D-5L index and EQ-VAS of parents by the prevalence of allergic symptoms (wheezing, runny or blocked nose, and itchy rash) in their children in the past 12 months. In addition, we examined the difference in parents' EQ-5D-5L index and EQ-VAS score, based on the number of allergic symptoms of their children. Results: Of the 23,837 completed questionnaires, 22,904 were analyzed. There were significant differences in HRQOL between parents of children with and without allergic symptoms. There was a considerable difference in proportion of problem reporting in the "pain/discomfort" and "anxiety/depression" dimensions compared with the remaining dimensions of the EQ-5D-5L. Among three allergic symptoms, the HRQOL of parents of children with asthmatic symptoms was lowest at 0.936 on the EQ-5D-5L index and 79.3 on the EQ-VAS score. As the number of allergic symptoms of children increased, QOL of parents significantly decreased. Conclusions: Parents of children with allergic symptoms showed lower HRQOL than those parents whose children did not. The EQ-5D-5L instrument appeared to be useful to evaluate the HRQOL of parents of children with allergic diseases.

Cost-utility analysis of the National Health Screening Program for chronic kidney disease in Korea.

AIM: Although a National Health Screening Program (NHSP) for chronic kidney disease (CKD) has been implemented in Korea since 2002, its cost-effectiveness has never been determined. This study aimed to estimate the cost-utility of NHSP for CKD in Korea. METHODS: A Markov decision analytic model was constructed to compare CKD screening strategies of the NHSP with no screening. We developed a model that simulated disease progression in a cohort aged 20-120 years or death from the societal perspective. RESULTS: Biannual screening starting at age 40 for CKD by proteinuria (dipstick) and estimated glomerular filtration ratio had an ICUR of $66 874/QALY relative to no screening. The targeted screening strategy had an ICUR of $37 812/QALY and $40 787/QALY for persons with diabetes and hypertension, respectively. ICURs improved with lower cost strategies. The most influential parameter that might make screening more cost-effective was the effectiveness of treatment on CKD to decrease disease progression and mortality. CONCLUSIONS: The Korean NHSP for CKD is more cost-effective for patients with diabetes or hypertension than the general population, consistent with prior studies. Although it is too early to conclude the cost-effectiveness of the Korean NHSP for CKD, this study provides evidence that is useful in evaluating the cost-effectiveness of CKD interventions.

Disease severity-based evaluation of utility weights for lung cancer-related health states in Korea.

BACKGROUND: Utility weight, a measure of health-related quality of life, is used in disease burden measurements and economic evaluations. In this study, we used the visual analogue scale (VAS) and standard gamble (SG) method to determine the utility weights of lung cancer health states in South Korea from a societal perspective. METHODS: Six hypothetical health states for lung cancer or a related health state reflective of disease severity were developed: 1) Stage I, 2) Stage II, 3) Stage IIIa, 4) Stage IIIB, 5) Stage IV, and 6) Pulmonary nodule. The description of each health state description was divided into four parts: diagnosis, symptoms, treatment, and progression and prognosis. A total of 515 representative adult Korean participants used a VAS and SG to evaluate these six health states via face-to-face computer-assisted interviews. The means, standard deviations, and median utility weights of the six health states were estimated by valuation method. RESULTS: The two valuation methods of the scenarios yielded the same mean utility rankings. Pulmonary nodule received the highest rank (VAS, 0.66 and SG, 0.83), whereas Stage 4 was assigned the lowest rank (VAS, 0.09 and SG, 0.31). For all health states, the mean utility weights calculated using the SG were greater than those calculated using the VAS. The differences between the utility weights obtained using the two valuation methods ranged from 0.14 (Stage I) to 0.22 (Stage IV). The two approaches tended to yield larger differences for more severe stages. CONCLUSIONS: This study determined utilities for squamous cell lung cancer that will be useful for estimating the burden of lung cancer and for conducting economic evaluations of lung cancer interventions.

Health-related quality of life by allergy symptoms in elementary school students.

BACKGROUND: Globally, allergic diseases are very common in childhood and may affect children's quality of life. This study aimed to explore health-related quality of life of elementary school students with allergy symptoms using the EQ-5D-Y and to examine the validity and feasibility of the EQ-5D-Y. METHODS: The study subjects were the students within 50 elementary schools which voluntarily participated in research project. In this sample population, the EQ-5D-Y questionnaire was self-administered by the students, and demographic and health information were collected from the student's parents. The parents' information was used to investigate the proportion of students with allergic symptoms (wheezing, runny or blocked nose, and itchy rash) in the past 12 months. In addition, we analyzed the correlation of symptom reporting and EQ-5D-Y including EQ-VAS. RESULTS: The overall return was 9117 responses, of which 198 (2.2%) lacked responses on the EQ-5D-Y dimension and 1258 (13.8%) on the VAS score. There were significant differences in symptom reporting in all EQ-5D-Y dimensions between groups with or without allergic symptoms. Particularly, there was a large difference in reporting rates in 'having pain or discomfort' and 'feeling worried, sad or unhappy' dimensions. As the number of allergic symptoms increased, in all dimensions also the problem reporting rate tended to increase. CONCLUSIONS: As expected, the presence of allergic symptoms is inversely correlated with the quality of life of children. The EQ-5D-Y instrument proved to be useful in terms of feasibility and construct validity in assessing the quality of life of Korean elementary school students.

Exploratory Study of Dimensions of Health-related Quality of Life in the General Population of South Korea.

OBJECTIVES: This study aimed to explore dimensions in addition to the 5 dimensions of the 5-level EQ-5D version (EQ-5D-5L) that could satisfactorily explain variation in health-related quality of life (HRQoL) in the general population of South Korea. METHODS: Domains related to HRQoL were searched through a review of existing HRQoL instruments. Among the 28 potential dimensions, the 5 dimensions of the EQ-5D-5L and 7 additional dimensions (vision, hearing, communication, cognitive function, social relationships, vitality, and sleep) were included. A representative sample of 600 subjects was selected for the survey, which was administered through face-to-face interviews. Subjects were asked to report problems in 12 health dimensions at 5 levels, as well as their self-rated health status using the EuroQol visual analogue scale (EQ-VAS) and a 5-point Likert scale. Among subjects who reported no problems for any of the parameters in the EQ-5D-5L, we analyzed the frequencies of problems in the additional dimensions. A linear regression model with the EQ-VAS as the dependent variable was performed to identify additional significant dimensions. RESULTS: Among respondents who reported full health on the EQ-5D-5L (n=365), 32% reported a problem for at least 1 additional dimension, and 14% reported worse than moderate self-rated health. Regression analysis revealed a R2 of 0.228 for the original EQ-5D-5L dimensions, 0.200 for the new dimensions, and 0.263 for the 12 dimensions together. Among the added dimensions, vitality and sleep were significantly associated with EQ-VAS scores. CONCLUSIONS: This study identified significant dimensions for assessing self-rated health among members of the general public, in addition to the 5 dimensions of the EQ-5D-5L. These dimensions could be considered for inclusion in a new preference-based instrument or for developing a country-specific HRQoL instrument.

Estimation of utility weights for major liver diseases according to disease severity in Korea.

BACKGROUND: The global burden of liver diseases, such as hepatocellular carcinoma and liver cirrhosis, is substantial. In this study, we estimated utility weights of liver disease-related health states in the general population using a visual analogue scale (VAS) and the standard gamble (SG) method. METHODS: Depictions of standardized health states related to major liver diseases were developed based on patient education materials and previous publications. To fully reflect disease progression from diagnosis to prognosis, each health state comprised four parts: diagnosis, symptoms, treatment, and progression and prognosis. A total of 407 participants from the Korean general population evaluated the health states using the VAS and SG methods in computer-assisted personal interviews. After excluding illogical responses, mean utility weights were calculated for each health state. RESULTS: The utility weights for health states were significantly different according to the existence of inconsistency in general. According to the VAS results, the health state with the highest utility was 'Chronic hepatitis B virus infection' (0.64), whereas the health state with the lowest utility was 'Hepatocellular carcinoma that requires palliative therapy' (0.17). Similarly, the SG results revealed that the health state with the highest utility was 'Chronic hepatitis B virus infection' (0.85), and the health state with the lowest utility was 'Hepatocellular carcinoma that requires palliative therapy' (0.40). CONCLUSIONS: The estimated utility weights in this study will be useful to measure the burden of liver diseases and evaluate cost-utility of programs for reducing the burden of liver diseases.

Feasibility, comparability, and reliability of the standard gamble compared with the rating scale and time trade-off techniques in Korean population.

PURPOSE: The standard gamble (SG) method is the gold standard for valuing health states as a utility, although it is accepted that it is difficult to valuate health states. This study was conducted in order to compare the SG with the rating scale (RS) and time trade-off (TTO) techniques in terms of their feasibility, comparability, and reliability in a valuation survey of the general Korean population. METHODS: Five-hundred members of the general Korean population were recruited using a multi-stage quota sampling method in Seoul and its surrounding areas, Korea. Respondents evaluated 9 EQ-5D-5L health states using a visual analogue scale (VAS), SG, and TTO during a personal interview. Feasibility was assessed in aspects of the level of difficulty, administration time, and inconsistent responses. Comparability was evaluated using intraclass correlation coefficient (ICC) and the Bland-Altman approach. Test-retest reliability was analyzed using the ICC. RESULTS: Of the three methods, VAS was the easiest and quickest method to respond. The SG method did not differ significantly compared to the TTO method in administration time as well as the level of difficulty. The SG and TTO values were highly correlated (r = 0.992), and the average mean difference between the SG and the TTO values was 0.034. The ICCs of the VAS, SG, and TTO scores were 0.906, 0.841, and 0.827, respectively. CONCLUSIONS: This study suggests that the SG method compared with the VAS and TTO method was feasible and offered a reliable tool for population-based, health state valuation studies in Korea.

Estimating utility weights and quality-adjusted life year loss for colorectal cancer-related health states in Korea.

We aimed to assess utility weight of health states associated with colorectal cancer (CRC) that reflect the societal preference of the Korean population and to estimate the quality-adjusted life year (QALY) loss with CRC. We recruited 607 individuals from the Korean population; they were surveyed via face-to-face computer-assisted interviews. The participants evaluated each CRC-associated health state using standard gamble. Utility weight for each health state was calculated as the possibility of full health restoration. Moreover, we estimated total QALY loss due to CRC in Korean individuals aged ≥30 years in 2013. To calculate QALY due to morbidity, we yielded utility weights and used epidemiologic data of CRC on severity from the National Cancer Control Institute. QALY loss due to mortality was calculated using mortality of CRC and life expectancy data from the Korean Statistical Information Service. The highest and lowest utility weights were assigned to "adenomatous polyps" and "metastatic colon cancer", respectively. Total QALY loss due to CRC in Korea was 173,662; these patients were more likely to be men or be included in the 70-74-year age group. These utility weights may be useful for conducting cost-utility studies of cancer screening for CRC and for measuring disease burden with QALY.

A cross sectional survey on health-related quality of life of elementary school students using the Korean version of the EQ-5D-Y.

BACKGROUND AND OBJECTIVE: The Korean version of the EQ-5D-Y was launched in 2015 by the EuroQol group. Currently, there is no HRQOL data obtained by using the EQ-5D-Y in Korea. This study aimed to measure health-related quality of life of Korean elementary school students using the EQ-5D-Y. METHODS: Elementary school students were recruited from 11 primary schools in Gyungbuk, South Korea. The EQ-5D-Y was self-administered in the sample population. Demographic characteristics were collected from the subjects' parents or guardians. The percentage of respondents reporting problems and VAS scores were calculated. Feasibility of the EQ-5D-Y was assessed by analysing the proportion of missing responses. The percentage of reported problems on the dimensions and VAS score between groups were compared by demographic factors. RESULTS: A total of 2,494 questionnaires were collected. There were 24 (0.96%) missing responses on the EQ-5D-Y and 187 (7.5%) missing VAS score responses. The proportion of reported problems ranged from 2.3% on the mobility dimension to 9.8% on the "having pain or discomfort" dimension. There was no significant difference in the proportion of problems by age group in male participants. However, in females, the older group reported significantly more problems on the "having pain or discomfort" and "feeling worried, sad, or unhappy" dimensions compared to the younger group. Students living with parents with the lowest educational level reported significantly more problems on the "looking after myself" and "doing usual activities" dimensions than did those living with parents with higher levels of education. DISCUSSION: This study showed the distribution of health-related quality of life and explored the feasibility of the EQ-5D-Y for measuring health-related quality of life in Korean elementary school students. Further studies are required to examine other psychometric properties of the Korean EQ-5D-Y.

Estimation of health state utilities in breast cancer.

PURPOSE: The aim of this study is to determine the utility of breast cancer health states using the standard gamble (SG) and visual analog scale (VAS) methods in the Korean general population. MATERIALS AND METHODS: Eight hypothetical breast cancer health states were developed based on patient education material and previous publications. Data from 509 individuals from the Korean general population were used to evaluate breast cancer health states using the VAS and the SG methods, which were obtained via computer-assisted personal interviews. Mean utility values were calculated for each human papillomavirus (HPV)-related health state. RESULTS: The rank of health states was identical between two valuation methods. SG values were higher than VAS values in all health states. The utility values derived from SG were 0.801 (noninvasive breast cancer with mastectomy and followed by reconstruction), 0.790 (noninvasive breast cancer with mastectomy only), 0.779 (noninvasive breast cancer with breast-conserving surgery and radiation therapy), 0.731 (invasive breast cancer with surgery, radiation therapy, and/or chemotherapy), 0.610 (locally advanced breast cancer with radical mastectomy with radiation therapy), 0.587 (inoperable locally advanced breast cancer), 0.496 (loco-regional recurrent breast cancer), and 0.352 (metastatic breast cancer). CONCLUSION: Our findings might be useful for economic evaluation of breast cancer screening and interventions in general populations.

Economic burden of chronic kidney disease in Korea using national sample cohort.

BACKGROUND: Determining the cost of a disease is one of the approaches to estimate the burden of the disease. This study was aimed to estimate the socioeconomic burden of chronic kidney disease (CKD) by CKD stages and treatment strategies in Korea. METHODS: This was a population-based study designed to estimate the cost of CKD according to CKD stages and treatment strategies from a societal perspective in Korea using multiple data sources. Costs of CKD stages III, IV, and V, hemodialysis (HD), and peritoneal dialysis (PD) were estimated with a prevalence-based method. Costs of kidney transplantation (KT) and post kidney transplantation were estimated using an incidence-based method. Costs consisted of direct medical cost, productivity loss cost due to hospitalization and outpatient visit, caregiver cost, and transportation cost. RESULTS: Direct medical cost per year per patient with CKD stages III, IV, and V were 1205, 1963, and 8035 Euros, respectively. Direct medical cost per year per patient receiving HD and PD was 34,554 and 25,806 Euros, respectively. Medical cost per year per KT patient was 68,798 Euros. Direct medical cost which accounted for 70% of the total cost of CKD IV and 87% of the total cost of post KT. Cost associated with productivity loss was approximately 8-20%. CONCLUSIONS: Our findings could be useful for evaluating cost-effectiveness of various CKD interventions including the screening strategy. This study also emphasizes a remarkable increase in the socioeconomic burden associated with the progression of CKD in patients.

Development and Validation of a Novel Generic Health-related Quality of Life Instrument With 20 Items (HINT-20).

OBJECTIVES: Few attempts have been made to develop a generic health-related quality of life (HRQoL) instrument and to examine its validity and reliability in Korea. We aimed to do this in our present study. METHODS: After a literature review of existing generic HRQoL instruments, a focus group discussion, in-depth interviews, and expert consultations, we selected 30 tentative items for a new HRQoL measure. These items were evaluated by assessing their ceiling effects, difficulty, and redundancy in the first survey. To validate the HRQoL instrument that was developed, known-groups validity and convergent/discriminant validity were evaluated and its test-retest reliability was examined in the second survey. RESULTS: Of the 30 items originally assessed for the HRQoL instrument, four were excluded due to high ceiling effects and six were removed due to redundancy. We ultimately developed a HRQoL instrument with a reduced number of 20 items, known as the Health-related Quality of Life Instrument with 20 items (HINT-20), incorporating physical, mental, social, and positive health dimensions. The results of the HINT-20 for known-groups validity were poorer in women, the elderly, and those with a low income. For convergent/discriminant validity, the correlation coefficients of items (except vitality) in the physical health dimension with the physical component summary of the Short Form 36 version 2 (SF-36v2) were generally higher than the correlations of those items with the mental component summary of the SF-36v2, and vice versa. Regarding test-retest reliability, the intraclass correlation coefficient of the total HINT-20 score was 0.813 (p<0.001). CONCLUSIONS: A novel generic HRQoL instrument, the HINT-20, was developed for the Korean general population and showed acceptable validity and reliability.