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Background The potential benefit of neoadjuvant chemotherapy (NAC) in colon cancer is under evaluation. There is a need to improve preoperative non-invasive diagnostics using techniques that provide more accurate staging information in assessing patient eligibility for NAC. Purpose To investigate the link between the tumor grade (pathohistological confirmed) and the N status (corresponding to lymph node involvement) with apparent diffusion coefficient (ADC) values. Material and Methods A total of 17 patients planned for surgical resection had a biopsy confirming colon carcinoma and participated in the study. Abdominal magnetic resonance imaging with diffusion-weighted imaging/ADC sequence was recorded before surgery. The tumor and all visible lymph nodes were manually delineated directly on a grayscale ADC map for every single slice and detected to access the total tumor and summarized lymph node volume. The mean ADC value was further calculated for the mean tumor and mean lymph node values. Results Low-grade tumors had a mean ADC equivalent to 1225 ± 170×10−6 mm2/s, and the coefficient of high-grade tumors was 1444 ± 69×10−6 mm2/s. The group of patients with positive lymph nodes in operative tissue samples (N+) exhibited lower mean ADC values (1023 ± 142×10−6 mm2/s) as opposed to the group without metastatic lymph nodes (N–) with ADC values of 1260 ± 231×10−6 mm2/s. Conclusion The mean whole-tumor ADC is associated with the histological tumor grade, and the mean ADC value of whole-volume abdominal lymph nodes could assume real nodal infiltration.

Additional file 2. Table overview of the hypotheses, outcome measures, statistical testsused and results.

Additional file 1. List of analyzed Cochrane systematic reviews and studies included.

Background: assessing the risk of bias (RoB) in included studies is one of the key methodological aspects of systematic reviews. Cochrane Systematic Reviews appraise RoB of randomised controlled trials (RCTs) with the Cochrane RoB tool. Detailed instructions for using the Cochrane RoB tool are provided in the Cochrane Handbook for Systematic Reviews of Interventions (the Cochrane Handbook). Objectives: to analyze adequacy of judgments about RoB for random sequence generation, and blinding of participants and personnel (performance bias) in Cochrane Systematic Reviews of randomized controlled trials (RCTs). Methods: we extracted judgments and supporting comments for random sequence generation and performance bias from Cochrane Reviews’ RoB tables using automated data scraping. We parsed all intervention descriptions, judgments about risk of performance bias, and comments supporting judgments into simple categories. We assessed adequacy of RoB judgments against recommendations from the Cochrane Handbook. Results: for analysis related to random sequence generation, we analysed 10, 103 RCTs that were included in 704 Cochrane Reviews. For 5706 RCTs, randomisation was not described, but for the remaining RCTs, it was indicated that randomisation was performed using computer/software/internet (N = 2850), random number table (N = 883), mechanical method (N = 359) or it was incomplete/inappropriate (N = 305). Overall, 1220/10, 103 trials (12%) did not have a RoB judgment in line with Cochrane Handbook guidance about randomisation. The highest proportion of misjudgements was found for trials with high RoB (28%), followed by those with low (20%) or unclear (3%) RoB. Therefore, one in eight judgments for the analysed domain in Cochrane Reviews was not in line with the Cochrane Handbook, and one in four of the judgments was 'high risk'. For performance bias, we analyzed judgments of 10, 429 RCTs included in 718 Cochrane Reviews. Overall, 1828 out of 6918 judgments (26%) for performance bias were not in line with the Cochrane Handbook and were therefore considered inadequate. In reviews where Cochrane authors have split the performance bias domain into two subdomains, based on blinded individuals, we found lower prevalence of inadequate risk of bias judgments, with 9% of judgements for blinding of participants, and 5.8% judgements for the blinding of personnel subdomain being judged inadequately. Conclusion: in Cochrane Reviews, RoB assessments for random sequence generation, and blinding of participants and personnel were frequently not in line with Cochrane Handbook recommendations. Our results can help authors of both Cochrane and non- Cochrane reviews, which use the Cochrane RoB tool to avoid making common mistakes when assessing RoB in included trials. Interventions to improve these assessments should be taken in consideration. Patient or healthcare consumer involvement: not applicable ; this was a methodological study, and we did not include patients or healthcare consumers in the study.

Additional file 2: Table S1. Inter rater raw agreement and variability for different categorizations od interventions

Additional file 3: Table S2. Overview of the hypotheses, outcome measures, statistical tests used and results.

Additional file 5: Table S4. More detailed differentiation of justifications (causes) for risk judgments with tests and interpretations

Additional file 4: Table S3. Overview of the variability of the prevalence of adequate RoB judgments throughout RoB domains and according to the type of intervention in observed trials with statistical tests and pairwise comparisons

Background: Adequate judging of risk of bias (RoB) for blinding of outcome assessors (detection bias) is important for supporting highest level of evidence. Materials & Methods: Judgments and supporting comments for detection bias were retrieved from RoB tables reported in Cochrane reviews. We categorized comments, and then compared judgment and supporting comment with instructions from the Cochrane Handbook. Results: We analyzed 8656 judgments for detection bias from 7626 trials included in 575 reviews. Overall, 1909 judgments (22%) were not in line with the Cochrane Handbook. In 9% of trials authors split the detection bias domain according to outcomes. Here, prevalence of inadequate judgments is 19%. Conclusion: Interventions to improve risk of bias assessments in systematic reviews should be explored.

Additional file 1. STROBE Statement - Checklist of items that should be included in reports of cross-sectional studies