• Communications for Statistical Applications and Methods
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• 제19권6호
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• pp.751-759
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• 2012

This paper proposes an alternative stratified randomized response model based on the model of Singh and Joarder (1997). It is shown numerically that the proposed stratified randomized response model is more efficient than Hong et al. (1994) (under proportional allocation) and Kim and Warde (2004) (under optimum allocation).

• 산업경영시스템학회지
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• 제29권2호
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• pp.58-66
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• 2006

This paper addresses the analysis of the travel distance and the number of storage location for storage location allocation methods in a warehouse system. The dedicated, randomized, combined and limited storage methods are considered. The combined and the limited storage methods are suggested here, which the combined storage method is to divide the storage locations into the dedicated storage area and the randomized storage area, and the limited storage method is to restrict the storage area of each product. Through a numerical example, the average travel distance between input/output point and the storage locations, and the number of storage location needed in the warehouse are compared between storage location allocation methods. The nearest randomized storage method is shown as the reasonable one in the travel distance and the number of storage location.

• Communications for Statistical Applications and Methods
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• 제16권4호
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• pp.595-603
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• 2009

통상적으로 표준적인 최적배분은 층별 조사비용을 고려하여 표본을 배분한다. 만일 조사단위당 비용이 서로 다를 경우 보다 현실적인 배분방법을 고려할 필요가 있다. 즉, 개별 조사단위의 특성에 따라 이익비용비를 최대로 하는 단위를 먼저 표본으로 고려하는 동적배분을 고려하였다. 이러한 관점에서 층별 표본수를 배분하고, 배분된 표본규모에 따라 임의로 표본을 선정하는 방식인 표준적인 최적배분과는 차이가 있다. 이 논문은 약물오용, 낙태, 알콜중독 등과 같은 민감한 특성을 조사하는 층화확률화 응답기법에 대해 각 층별로 표본을 배분할 경우 최적 동적배분을 고려하여 보다 현실적인 문제를 해결하고자 하였으며, 수치적 예제를 통해 동적배분 방법의 효과성을 증명하였다.

• 응용통계연구
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• 제28권6호
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• pp.1113-1120
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• 2015

본 논문에서는 사회적으로나 개인적으로 매우 민감한 조사에서 세대별, 연령별 또는 계층별에 따라 조사하고자 하는 모집단이 여러 개의 층으로 구성되어 있고, 각 층이 다지속성으로 되어 있는 경우에, Abul-Ela 등의 다지모형과 Eriksson의 다지무관모형에서 사용한 단순임의추출법 대신에 층화추출법을 적용하여 각 층의 다지속성에 대한 모비율의 추정뿐만 아니라 모집단 전체 모비율에 대한 추정을 할 수 있는 층화 다지 확률화응답모형을 제안하였다. 그리고 층화 다지모형에 있어서 각 층의 표본배분에 대하여 비례배분과 최적배분을 고려하여 다루었다. 또한 층화 다지 확률화응답모형들간의 효율성을 비교해 본 결과 Eriksson의 다지무관모형이 Abul-Ela 등의 다지모형보다 효율적임을 알 수 있었다.

• 혜화의학회지
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• 제24권1호
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• pp.25-36
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• 2015

Objective : This study aims to evaluate a risk of bias by Risk of Bias tool and RoBANS(Risk of Bias Assessment tool for Non-randomized Study) tool for clinical trial papers proving treatment effect of herbs to alopecia and provides the newest reason of effectiveness of herbs to alopecia. Methos : Data were collected through electronic database including NDSL, KISS, KMBASE, Koreantk, OASIS, KoreaMed, KISTI, Pubmd, Cochrane CENTRAL and CINAHL. Two experts in Oriental Medince assessed risk of bias of randomized controlled trials by Cochrane group's Risk of Bias tool and non-randomized controlled trials by RoBANS tool after searching, reviewing and selecting papers. Results : Total number of selected trials is 20 including 4 randomized controlled trials, 13 non-randomized controlled trials and 3 case reports. This study evaluates the risk of bias of 17 papers including 4 randomized controlled trials and 13 non-randomized controlled trials except 3 case reports by risk of bias tool and RoBANS tool. All papers of randomized controlled trials are evaluated unclear for random sequence generation and allocation concealment as there are no word on them. And all papers of non-randomized controlled trials are evaluated unclear for blinding of outcome assessments and relatively low for others. Conclusion : We must try to specify concretely methods of allocation concealment after planning and practicing it for reducing a selection bias in randomized controlled trials. Also report a reason of missing value and blinding outcome assessments. And we have to agonize and mention methods of blinding of researchers for reducing a detection bias in non-randomized controlled trials.

• 의학교육논단
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• 제10권2호
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• pp.25-44
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• 2008

Objectives: Through using of the strong research method like a Randomized Controlled Trial: RCT, we have to heighten quality of Medical Education study. I'd like to introduce "CONSORT", which stands for Consolidated Standards of Reporting Trials. Contents: Preventive Service Task Force(200l) in USA proposed Levels of evidence for enlarging evidence-based Practice: EBP. And the CONSORT was introduced, which encompasses various initiatives developed by the CONSORT Group to alleviate the problems arising from inadequate reporting of randomized controlled trials (RCTs). the CONSORT has 13 guides like these: 1. How participants were allocated to interventions 2. Scientific background and explanation of rationale 3. Eligibility criteria for participants. The settings and locations where the data were collected. 4. Precise details of the interventions intended for each group and how and when they were actually administered 5. Specific objectives and hypotheses 6. Clearly defined primary and secondary outcome measures, When applicable. any methods to enhance the quality of measurements (e.g., multiple observations, training of assessors) 7. How sample size was determined. When applicable, explanation of any interim analyses and stopping rules 8. Method used to generate the random allocation sequence, Details of any restriction [of randomization] 9. Method used to implement the random allocation sequence 10. Who generated the allocation sequence, who enrolled participants. and who assigned participants to their groups 11. Whether or not participants, those administering the interventions, and those assessing the outcomes were blinded to group assignment. If done, how the success of blinding was evaluated 12. Statistical methods used to compare groups for primary outcome(s), Methods for additional analyses, such as subgroup analyses and adjusted analyses 13. Flow of participants through each stage (a diagram is strongly recommended) Specifically, for each group report the numbers of participants randomly assigned. receiving intended treatment, completing the study protocol. and analyzed for the primary outcome. Results and Conclusion: Randomized Controlled Trial: RCT guided of CONSORT will contribute to do stronger evidence-based medical studies.

• 대한한의학회지
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• 제30권5호
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• pp.115-126
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• 2009

Objective: By assessing the quality of methodology and synthesis of results of RCTs (Randomized Controlled Clinical Trials) with herbal acupuncture (pharmacopuncture), we hope to help with administrating herbal acupuncture therapy in clinic and conducting RCT with herbal acupuncture. Methods: Reports of RCT conducted in Korea published in medical journals until February 2009 were collected. We surveyed elementary information of RCTs, evaluated randomization, double-blinding, allocation concealment and put together the results of RCTs by seven clinical topics. Results: 38 RCTs with herbal acupuncture were selected, then adequate methods for randomization and allocation concealment were found in 39% and 5% of studies. Complete double-blinding and a clear accounting of all participants were conducted in 42% and 50% of reports. The synthesis of RCTs revealed that herbal acupuncture was useful and effective on degenerative gonarthritis, omarthralgia on cerebrovascular accident, acute ankle sprain, back sprain, neck sprain, headache, rheumatoid arthritis and tennis elbow, generally. Conclusions: Although further improvement in quality of methodology of RCTs with herbal acupuncture is required, clinical usefulness of herbal acupuncture was shown especially on disorders of musculoskeletal system via RCTs.

• 동의생리병리학회지
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• 제25권5호
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• pp.927-933
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• 2011

This study aimed to evaluate the quality of herbal medicine-related RCT (Randomized controlled clinical trial) papers. 79 papers were searched from the domestic Hakjin paper list, and 16 papers of them were evaluated in terms of the Jadad Quality Assessment Scale and the adequacy of allocation concealment, and ethical validity. The evaluation results from Jadad Quality Assessment Scale showed that 15 papers showed high quality with the Jadad score of 3 points or higher, and none of the papers had a problem with randomization and double-blinding. The evaluation results from adequacy of allocation concealment showed that 3 of the papers were executed proper allocation concealment, and all of them had 5 points of Jadad score. IRB (Institutional Review Board) approval and written consent was investigated for the evaluation of ethical validity, and 12 papers had the IRB approval, and 14 papers had written consent. The papers published before 2005 were absent of IRB approval and written consent, and none of the papers had IRB approval number. From the above results, it is concluded that rigorous clinical research led high quality of research papers, and the ethical aspect of clinical researches are getting more important to protect the rights of research participants.

• Journal of the Korean Statistical Society
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• 제14권1호
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• pp.48-55
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• 1985

In clinical trials subjects are avalible sequentially and must be assigned to treatments immediately. Completely randomized procedure for the allocation of treatments to each subject may result in severe imbalance among the number of subjects in treatment groups, especially for small experiments or interim analyses of large experiments. In this study, restricted randomization methods such as biased coin designs (Efron, 1971), permuted block design, and truncated binomial design are compared to teh completely randomized design in the presence of selection and/or accidential bias by Monte Carlo simulations.

• Journal of information and communication convergence engineering
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• 제16권1호
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• pp.38-42
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• 2018

In this paper, we consider measurement allocation problem in a spatially correlated sensor field. Our goal is to determine the probability of each sensor's being measured based on its contribution to the estimation reliability; it is desirable that a sensor improving the estimation reliability is measured more frequently. We consider a spatial correlation model of a sensor field reflecting transmission power limit, noise in measurement and transmission channel, and channel attenuation. Then the estimation reliability is defined distortion error between event source and its estimation at sink. Motivated by the correlation nature, we model the measurement allocation problem into a cooperative game, and then quantify each sensor's contribution using Shapley value. Against the intractability in the computation of exact Shapley value, we deploy a randomized method that enables to compute the approximate Shapley value within a reasonable time. Besides, we envisage a measurement scheduling achieving the balance between network lifetime and estimation reliability.