• Title/Summary/Keyword: False-negative results

Search Result 307, Processing Time 0.03 seconds

친환경 패션제품에 대한 소비자 혼란과 가치, 가격민감성 연구 (A study on consumer confusion, value, and price sensitivity of eco-friendly fashion product)

  • 신상무;임유라
    • 복식문화연구
    • /
    • 제29권1호
    • /
    • pp.48-64
    • /
    • 2021
  • Eco-friendly consumption is a prominent trend in the fashion industry, by which many firms attract the interest of consumers using a green marketing strategy. However, "greenwashing" (caused by distorted, exaggerated, and false information) gives rise to consumer confusion. The purpose of this study is to investigate the effect of consumer confusion and value on price sensitivity and purchase intention. Data was collected from 228 respondents using a questionnaire that was distributed to consumers living in Seoul and Kyunggi, South Korea. The data was analyzed by factor analysis, regression analysis, and Cronbach's alpha using SPSS 23.0. The results were as follows: First, factor analysis showed the consumer value variable was significantly categorized in altruistic and self-expressive values. All variables (altruism, selfexpression, consumer confusion, price sensitivity, and purchase intention) were shown to have significantly good internal validity. Second, altruistic consumer value was shown to positively affect the purchase intention of eco-friendly fashion products, but self-expressive consumer value had no significant effect. Third, consumer confusion on eco-friendly fashion products had a negative effect on purchase intention. Fourth, altruistic and self-expressive consumer values had no effect on price sensitivity. Fifth, consumer confusion on eco-friendly fashion products positively affect price sensitivity. Sixth, price sensitivity on eco-friendly fashion products had a negative effect on purchase intention. Therefore, fashion firms should provide a certified green mark to consumers to eliminate confusion and deliver the right message without greenwashing. Moreover, fashion firms should develop green marketing strategies that are more focused on altruistic consumers.

양방향 GPT 네트워크를 이용한 VMS 메시지 이상 탐지 (Detection of Anomaly VMS Messages Using Bi-Directional GPT Networks)

  • 최효림;박승영
    • 한국ITS학회 논문지
    • /
    • 제21권4호
    • /
    • pp.125-144
    • /
    • 2022
  • VMS (variable message signs) 시스템이 악의적인 공격에 노출되어 교통안전과 관련된 거짓 정보를 출력하게 된다면 운전자에게 심각한 위험을 초래할 수 있다. 이러한 경우를 방지하기 위해 VMS 시스템에 사용되는 메시지들을 수집하여 평상시의 패턴을 학습한다면 VMS 시스템에 출력될 수 있는 이상 메시지를 빠르게 감지하고 이에 대한 대응을 할 수 있을 것이다. 본 논문에서는 양방향 GPT (generative pre-trained transformer) 모델을 이용하여 VMS 메시지의 평상 시 패턴을 학습한 후 이상 메시지를 탐지하는 기법을 제안한다. 구체적으로, 제안된 기법에 VMS 메시지 및 시스템 파라미터를 입력 하고 이에 대한 NLL (negative log likelihood) 값을 최소화하도록 학습한다. 학습이 완료되면 판정해야 할 대상의 NLL 값을 계산한 후, 문턱치 값 이상일 경우 이를 이상으로 판정한다. 실험 결과를 통해, 공격에 의한 악의적인 메시지 탐지뿐만 아니라 시스템의 오류가 발생하는 상황에 대한 탐지도 가능함을 보였다.

수면무호흡증후군의 선별검사로서 임상양상과 산소포화도 이용 (Application of Clinical Features and the Degree of Oxygen Desaturation as a Screening Test for the Obstructive Sleep Apnea Syndrome)

  • 고재광;김인;서광윤;신동균
    • 수면정신생리
    • /
    • 제1권1호
    • /
    • pp.60-67
    • /
    • 1994
  • Objectives: The Obstructive sleep apnea syndrome is characterized by snoring, observed apnea during sleep and excessive daytime sleepiness. The overnight polysomnographic recording is used to investigate patients with possible obstructive sleep apnea syndrome. But the overnight polysomnographic recording is time consuming, expensive, and labor-intensive. Recently in diagnosis of obstructive sleep apnea syndrome, several simple screening tests have been suggested. Methods: This study was performed to assess the probability of application of clinical features and the degree of oxygen desaturation as a screening test for the obstructive sleep apnea syndrome. The sensitivity and specificity of the self-report of clinical features including snoring, observed apnea during sleep, excessive daytime sleepiness and insomnia were tested. And the degree of oxygen desaturation measured by oximetry in 42 subjects were compared with the overnight polysomnographic recording results. Results: In the prediction of apnea index more than 5, the sensitivity of observed apnea during sleep, snoring, excessive daytime sleepiness and insomnia were 96.8%, 93.5%, 38.7%, 25.8% and the specificity of those clinical features were 182%, 36.4%, 100%, 72.7%, respectively. In the prediction of apnea index more than 5, the sensitivity and specificity of the combination of more than three self-report clinical features were 54.8% and 90.9%. The degree of oxygen de saturation and maximal apnea duration in the group of apnea index more than 5 were significantly different from those in the group of apnea index below 5(P<0.001). And the apnea index was significantly correlated with the degree of oxygen desaturation and maximal apnea duration(P<0.001). Conclusion: These results suggest that application of clinical features alone as a screening test for the obstructive sleep apnea syndrome is inadequate because of it's high rate of false positive and false negative results. The degree of oxygen desaturation measured by oximetry is possibly applicable to screening test and follow up evaluation of treatment efficacy for the obstructive sleep apnea syndrome.

  • PDF

Accuracy of FDG-PET/CT for Detection of Incidental Pre-Malignant and Malignant Colonic Lesions - Correlation with Colonoscopic and Histopathologic Findings

  • Kunawudhi, Anchisa;Wong, Alexandra K;Alkasab, Tarik K;Mahmood, Umar
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제17권8호
    • /
    • pp.4143-4147
    • /
    • 2016
  • Purpose: We evaluated all PET/CTs acquired for patients without a primary diagnosis of colorectal cancer, and compared results for those who had subsequent colonoscopy within 6 months, to assess the accuracy of FDG PET/CT for detection of incidental pre-malignant polyps and malignant colon cancers. Materials and Methods: Medical records of 9,545 patients who underwent F-18 FDG PET/CT studies over 3.5 years were retrospectively reviewed. Due to pre-existing diagnosis of colorectal cancer, 818 patients were excluded. Of the remainder, 157 patients had colonoscopy within 6 months (79 males; mean age 61). We divided the colon into 4 regions and compared PET/CT results for each region with colonoscopy and histopathologic findings. True positive lesions included colorectal cancer, villous adenoma, tubulovillous adenoma, tubular adenoma and serrated hyperplastic polyp/hyperplastic polyposis. Results: Of 157 patients, 44 had incidental colonic uptake on PET/CT (28%). Of those, 25 had true positive (TP) uptake, yielding a 48% positive predictive value (PPV); 9% (4/44) were adenocarcinoma. There were 23 false positive (FP) lesions of which 4 were hyperplastic polyp, one was juvenile polyp and 7 were explained by diverticulitis. Fifty eight patients had false negative PET scans but colonoscopy revealed true pre-malignant and malignant pathology, yielding 23% sensitivity. The specificity, negiative predictive value (NPV) and accuracy were 96%, 90% and 87%, respectively. The average SUVmax values of TP, FP and FN lesions were 7.25, 6.11 and 2.76, respectively. There were no significant difference between SUVmax of TP lesions and FP lesions (p>0.95) but significantly higher than in FN lesions (p<0.001). The average size (by histopathology and colonoscopy) of TP lesions was 18.1 mm, statistically different from that of FN lesions which was 5.9 mm (p<0.001). Fifty-one percent of FN lesions were smaller than 5 mm (29/57) and 88% smaller than 10 mm (50/57). Conclusions: The high positive predictive value of incidental focal colonic FDG uptake of 48% for colonic neoplasia suggests that colonoscopy follow-up is warranted with this finding. We observed a low sensitivity of standardly acquired FDG-PET/CT for detecting small polyps, especially those less than 5 mm. Clinician and radiologists should be aware of the high PPV of focal colonic uptake reflecting pre-malignant and malignant lesions, and the need for appropriate follow up.

임상 검체에서 결핵균 검출을 위한 항산성염색, PCR, LCR, PCR-Hybridization 검사법 간의 비교 (Comparison of Acid-Fast Staining, PCR, LCR, PCR-Hybridization for Detection of Mycobacterum Tuberculosis in Clinical Specimens)

  • 최종락;임종백;김현중
    • Tuberculosis and Respiratory Diseases
    • /
    • 제49권3호
    • /
    • pp.281-289
    • /
    • 2000
  • 배경 : 결핵의 진단에 있어 결핵균 배양검사는 결핵의 확진 검사이지만 배양에 최소한 6-8주가 소요되어 진단 및 치료가 지연되는 단점이 있다. PCR 법은 신속하고 예민하게 결핵균을 검출할 수 있지만 위양성율과 위음성율이 높아 문제시 되고 있다. 최근에 개발된 LCR법과 PCR-Hybridization은 PCR 법 보다도 민감하게 결핵균을 검출할 수 있는 것으로 알려져 있다. 이에 저자들은 하상균 배양을 기준으로 in house PCR, LCR 및 PCR- Hybridization 각각의 임상적 유용성을 알아보고자 한다. 방법 : 1998년 8월에 결핵진단을 위해 세브란스 병원 임상 병리과에 의뢰된 75검체를 대상으로 AFB 도말 염색 검사, 결핵균 배양 검사(3% Ogawa 배지, 8주간), in house PCR, LCR(Abbott LCx kit) 및 PCR Hybridization을 시행하여 각각의 민간도와 특이도를 평가해보았다. 결과 : 항산균 배양법을 기준으로 판단할 때 in house PCR, LCR(Abbott LCx kit) 및 PCR-Hybridization의 민감도는 각각 40%, 80%, 100%였고 특이도는 98.6%, 94.3%, 94.3%였다. 결론 : LCR법과 PCR-Hybridization은 결핵균 검출에 있어 우수한 민감도와 특이도를 보여 결핵의 조기진단에 유용할 것으로 사료된다.

  • PDF

LAL Test에서 위양성을 나타내는 원인들에 대한 고찰 (Consideration About the Bacterial Endotoxin Test Showing False Positive Test Result When Performing LAL Test)

  • 황기영;조용현;이용석;김형우;이홍재;김현주
    • 핵의학기술
    • /
    • 제13권3호
    • /
    • pp.156-158
    • /
    • 2009
  • 환자 몸에 투여되는 주사용제재으로서 약품 내 무균성이 요구되어진다. 현재 대부분의 방사성약품합성 실에서는 사용하기가 비교적 간편하고 민감도가 우수한 Bacterial Endotoxin Test로 방사성약품 내 발열성물질이 존재하는지의 유무를 실험한다. 그렇지만 테스트결과를 해석할 때 가끔씩 위 양성의 결과를 나타내서 결과를 해석 시 혼란을 줄 때도 있다. 이 위 양성의 원인을 알아보기 위해 pH영역이 다른 buffer와 Ethanol sample을 사용해서 실험을 해보았다. 그 결과 pH영역이 너무 산성이나 염기성인 1.0~5.0 그리고 11.2~12.6에서 위 양성의 결과를 나타냈고 Ethanol sample에 있어서는 20~50%에서는 위 양성의 결과를 100%에서는 완전한 양성의 결과를 나타내었다. Pyrogen은 면역력이 약한 환자들에게 있어서 두통이나 발열, 백혈구감소증 등의 증상을 일으키고 심지어 합병증으로 인해 환자들에게 치명적인 반응을 일으키기도 한다. 그러므로 우리는 위양성의 결과에 영향 미치는 이런 요인들을 최대한 배제함으로써 객관적이고 신뢰할만한 Pyrogen test결과를 도출하는게 필요하다.

  • PDF

자궁내막암의 치료 후 루틴 추적검사 방법으로서 FDG-PET/CT의 유용성 (Usefulness of FDG-PET/CT as a Diagnostic Tool for Routine Post Therapy Evaluation in Endometrial Cancer)

  • 이신재;전태주;김승조;김희진;안희정
    • Nuclear Medicine and Molecular Imaging
    • /
    • 제43권4호
    • /
    • pp.301-308
    • /
    • 2009
  • 목적: 자궁내막암의 치료 후 루틴 추적관찰로써의 FDG-PET/ET의 유용성에 대해 알아보고자 하였다. 대상 및 방법: 자궁내막암으로 치료 받은 환자 중 2004년 1월 1일부터 2008년 1월 31일 사이에 FDG-PET/CT를 시행한 101명의 환자(25-79세, 평균 50.6세)를 대상으로 하였다. 모든 환자에서 종양표지 자와 다른 영상의학적 검사(CT, MR)에 대해서도 함께 검토하였다. FDG-PET/CT상 국소 FDG 섭취를 보인 병변을 benign, equivocal, malignant로 분류하였고, equivocal과 maliganat 병변에 대하여 조직학적 혹은 임상적으로 재발유무를 판정하였다. 결과: FDG-PET/CT상 강한 섭취를 보인 경우는 19명의 30개의 병변이었다. Malignant 섭취를 보인 환자는 14명이었고, 이중 11예가 재발로 확인되었다. Equivocal 병변을 보인 환자는 5명 이었고, 이중 1예가 재발로 확인되었다. 위음성을 보인 경우는 2예가 있었고, 모두 복강내 암종증 환자로 진단되었다. 이상의 결과를 종합하였을 때, 자궁내막암의 치료 후 재발의 평가에 대한 전반적인 결과는 예민도 86 %,특이도 92 %, 양성 예측도 63 %, 음성예측도 98 %, 그리고 정확도는 91 %였다. 결론: 자궁내막암의 치료 후 루틴 추적관찰로써 FDG-PET/ET를 시행할 경우 높은 예민도, 특이도로 재발의 진단에 도움이 될 뿐만 아니라 높은 음성 예측도로 인하여 FDG-PET/CT상 음성인 경우 불필요한 추가 검사를 피할 수 있을 것으로 기대된다.

Noninvasive prenatal test for fetal chromosomal aneuploidies by massively parallel sequencing of cell-free fetal DNA in maternal plasma: The first clinical experience in Korea

  • Han, Sung-Hee;Yang, Young-Ho;Ryu, Jae-Song;Kang, Myung-Soo;Kim, Young-Jin;Lee, Kyoung-Ryul
    • Journal of Genetic Medicine
    • /
    • 제12권2호
    • /
    • pp.85-91
    • /
    • 2015
  • Purpose: Noninvasive prenatal test (NIPT) by massively parallel sequencing (MPS) of cell-free fetal DNA in maternal plasma marks a significant advancement in prenatal screening, minimizing the need for invasive testing of fetal chromosomal aneuploidies. Here, we report the initial clinical performance of NIPT in Korean pregnant women. Materials and Methods: MPS-based NIPT was performed on 910 cases; 5 mL blood samples were collected and sequenced in the Shenzhen BGI Genomic Laboratory to identify aneuploidies. The risk of fetal aneuploidy was determined by L-score and t-score, and classified as high or low. The NIPT results were validated by karyotyping for the high-risk cases and neonatal follow-up for low-risk cases. Results: NIPT was mainly requested for two clinical indications: abnormal biochemical serum-screening result (54.3%) and advanced maternal age (31.4%). Among 494 cases with abnormal biochemical serum-screening results, NIPT detected only 9 (1.8%) high-risk cases. Sixteen cases (1.8%) of 910 had a high risk for aneuploidy: 8 for trisomy 21, 2 for trisomy 18, 1 for trisomy 13, and 5 for sex chromosome abnormalities. Amniocentesis was performed for 7 of these cases (43.8%). In the karyotyping and neonatal data, no false positive or negative results were observed in our study. Conclusion: MPS-based NIPT detects fetal chromosomal aneuploidies with high accuracy. Introduction of NIPT as into clinical settings could prevent about 98% of unnecessary invasive diagnostic procedures.

토픽 모델링을 활용한 광범위 선천성 대사이상 신생아 선별검사 관련 온라인 육아 커뮤니티 게시 글 분석: 계량적 내용분석 연구 (Analysis of online parenting community posts on expanded newborn screening for metabolic disorders using topic modeling: a quantitative content analysis)

  • 이명선;정현숙;김진선
    • 여성건강간호학회지
    • /
    • 제29권1호
    • /
    • pp.20-31
    • /
    • 2023
  • Purpose: As more newborns have received expanded newborn screening (NBS) for metabolic disorders, the overall number of false-positive results has increased. The purpose of this study was to explore the psychological impacts experienced by mothers related to the NBS process. Methods: An online parenting community in Korea was selected, and questions regarding NBS were collected using web crawling for the period from October 2018 to August 2021. In total, 634 posts were analyzed. The collected unstructured text data were preprocessed, and keyword analysis, topic modeling, and visualization were performed. Results: Of 1,057 words extracted from posts, the top keyword based on 'term frequency-inverse document frequency' values was "hypothyroidism," followed by "discharge," "close examination," "thyroid-stimulating hormone levels," and "jaundice." The top keyword based on the simple frequency of appearance was "XXX hospital," followed by "close examination," "discharge," "breastfeeding," "hypothyroidism," and "professor." As a result of LDA topic modeling, posts related to inborn errors of metabolism (IEMs) were classified into four main themes: "confirmatory tests of IEMs," "mother and newborn with thyroid function problems," "retests of IEMs," and "feeding related to IEMs." Mothers experienced substantial frustration, stress, and anxiety when they received positive NBS results. Conclusion: The online parenting community played an important role in acquiring and sharing information, as well as psychological support related to NBS in newborn mothers. Nurses can use this study's findings to develop timely and evidence-based information for parents whose children receive positive NBS results to reduce the negative psychological impact.

F-18-FDG PET을 이용한 유방종괴의 감별진단과 유방암의 병기설정 (Differential Diagnosis of Breast Mass and Staging of Breast Cancer Using F-18-FDG PET)

  • 여정석;이동수;강건욱;노동영;정준기;이명철
    • 대한핵의학회지
    • /
    • 제33권6호
    • /
    • pp.502-511
    • /
    • 1999
  • 목적: 유방종괴를 감별진단하고 액와림프절전이를 진단하는 데 대한 F-18 FDG PET의 진단정확도를 알아보고자 하였다. 대상 및 방법: 수술 전 F-18 FDG PET을 시행한 42명의 환자에 대하여 PET의 진단성능을 수술 후 조직 소견과 비교하였다. 결과: F-18 FDG PET에 이상이 있고 수술한 20명의 환자중 19명에서 암이 확인되었다. 반면 F-18 FDG PET에 이상 소견이 없는 상태에서 수술한 2명의 환자는 모두 양성종양이었다. F-18 FDG PET에 이상 소견이 없고 추적관찰만 한 환자 16명에서는 모두 암의 증거가 없었다. 수술로 확인된 F-18 FDG PET의 유방종괴 감별진단력은 예민도 95% (19/20) 특이도 17% (7/9), 양성예측도 86% (19/22), 음성예측도 87% (7/8)였다. 위양성은 염증 소견이 동반되었던 경우였고 위음성은 종양조직이 매우 적었던 경우였다. 과거에 유방성형술을 받았던 환자군 17명에서 F-18 FDG PET의 음성예측도는 93% (13/14)였다. 액와탐색수술을 시행한 17명의 환자에서 F-18 FDG PET의 예민도는 73% (8/11), 특이도는 100% (7/7), 양성예측도는 100% (8/8), 음성예측도는 70% (7/0)였다. 수술시 유방종괴가 양성종양으로 확인되어 더 이상 그쪽 액와탐색수술하지 않았던 예를 F-18-FDG PET이 모두 음성결과를 보였던 것까지 포함하면 음성예측도는 87% (20/23)였다. 결론: 유방암 환자에서 F-18-FDG PET의 진단성능이 우수하였고 액와림프절전이의 진단에 도움이 된다.

  • PDF