Dataset Information

Observer agreement for diagnosis of colorectal lesions with analysis of the vascular pattern by image-enhanced endoscopy.

ABSTRACT: BACKGROUND/AIMS: Image-enhanced endoscopy (IEE) can differentiate neoplastic from non-neoplastic colorectal lesions through indirect analysis of pit patterns and microvascular architecture. We evaluated the accuracy of Flexible Spectral Imaging Color Enhancement (FICE) in differentiating neoplastic from non-neoplastic lesions and observer agreement in the analysis of capillary pattern of colorectal lesions. METHODS: A prospective double-blind trial was conducted in two referral endoscopy centers. Vascular pattern was analyzed by IEE with magnification. Lesions were divided into two groups and examined separately by two experts. Examiners, blinded to each other's interpretations, switched groups and the lesions were reviewed. After 60 days, lesions were reevaluated. RESULTS: In total, 76 patients were referred to colonoscopy for colon cancer screening. Of 100 colorectal lesions, 88 were neoplastic (73 tubular adenomas, 10 tubulovillous adenomas, 1 villous adenoma, 2 serrated adenomas, 2 adenocarcinomas) and 12 were non-neoplastic (hyperplastic polyps). Mean diameter of the lesions was 6.7 mm. Examiners 1 and 2 had 95 % accuracy. The interobserver kappa coefficient was 0.80 and the intraobserver kappa coefficient was 0.88 for examiner 1 and 0.73 for examiner 2. CONCLUSION: IEE with magnification is effective for real-time predictive histological diagnosis of colorectal lesions, with inter- and intraobserver agreement ranging from good to excellent.

SUBMITTER: Dos Santos CE

PROVIDER: S-EPMC4486027 | biostudies-other | 2015 Jun

REPOSITORIES: biostudies-other

ACCESS DATA

Similar Datasets

Project description:BackgroundRecent developments in diagnostic techniques for malaria, particularly DNA probes and sero-immunology, have raised questions as to how these techniques might be used to facilitate malaria diagnosis at the most peripheral levels of the primary health care system. At present, malaria diagnosis is based on the standard microscopic examination of blood films in most field epidemiologic studies and is likely to remain so in the immediate future in Africa. The objective of this study was to assess inter-observer agreement for the examination of Giemsa-stained slides for Plasmodium falciparum parasites.MethodsChildren aged 0 to 10 years were enrolled yearly in Bancoumana village (West Africa), mainly during the transmission season (June to October). The blood smears obtained from the persistently negative children in June 1996, August 1996, October 1996 and March 1997 were systematically re-examined. A stratified random sample (10%) proportional to the following parasite density classes 1-100, 101-5000, and 5001 and over was taken from the slides collected. The kappa statistics and the intra-class correlation were used as measures of agreement the first and the second slide examinations.ResultsThe weighted kappa statistic, widely used as a chance-corrected measure for nominal agreement, showed excellent inter-observer agreement (?(w)=0.7926; 95% CI [0.7588, 0.8263]; p=0.01). The intra-class correlation co-efficient had the same value of 0.7926 confirming the appropriateness of the weighted kappa statistic. Inter-observer agreement for slides read as negative by one observer, or as containing more than 100 parasites per ?l, was excellent: 97% (493/506) and 92% (145/158), respectively. In contrast, the inter-observer agreement for slides read by one observer as containing 1-100 parasites/?l was poor, 36% (96/268).ConclusionsIn field conditions in Mali, there was a high reproducibility for slides reported as negative or as having more than 100 parasites per ?l. However, smears with readings of 1-100 parasites per ?l were less reproducible and should be re-examined carefully.

Project description:Our aim was to evaluate the interobserver agreement in 18F-sodium fluoride (NaF) PET/CT for the detection of bone metastases in patients with prostate cancer (PCa). Methods: 18F-NaF PET/CT scans were retrieved from all patients who participated in 4 recent prospective trials. Two experienced observers independently evaluated the 18F-NaF PET/CT scans on a patient level using a 3-category scale (no bone metastases [M0], equivocal for bone metastases, and bone metastases present [M1]) and on a dichotomous scale (M0/M1). In patients with no more than 10 lesions, the location and number of lesions were recorded. On a patient level, the diagnostic performance was calculated using a sensitivity analysis, in which equivocal lesions were handled as M0 as well as M1. Results: 18F-NaF PET/CT scans from 219 patients with PCa were included, of whom 129 patients were scanned for primary staging, 67 for biochemical recurrence, and 23 for metastatic castration-resistant PCa. Agreement between the observers was almost perfect on a patient level (3-category unweighted ? = 0.83 ± 0.05, linear weighted ? = 0.90 ± 0.06, and dichotomous ? = 0.91 ± 0.07). On a lesion level (dichotomous scale), the observers agreed on the number and location of bone metastases in 205 (93.6%) patients. In the remaining 14 patients, the readers disagreed on the number of lesions in 13 patients and the location of bone metastases in 1 patient. A final diagnosis of bone metastases was made for 211 of 219 patients. The sensitivity ranged from 0.86 to 0.92, specificity from 0.83 to 0.97, positive predictive value from 0.70 to 0.93, and negative predictive value from 0.94 to 0.96. Conclusion: The interobserver agreement on 18F-NaF PET/CT for the detection of bone metastases in patients with PCa was very high among trained observers, both on a patient level and on a lesion level. Moreover, the diagnostic performance of 18F-NaF PET/CT was satisfactory, rendering 18F-NaF PET/CT a robust tool in the diagnostic armamentarium.

Dataset Information

Observer agreement for diagnosis of colorectal lesions with analysis of the vascular pattern by image-enhanced endoscopy.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure