Association of Accuracy, Conclusions, and Reporting Completeness With Acceptance by Radiology Conferences and Journals.

BACKGROUND: Preferential publication of studies with positive findings can lead to overestimation of diagnostic test accuracy (i.e. publication bias). Understanding the contribution of the editorial process to publication bias could inform interventions to optimize the evidence guiding clinical decisions. PURPOSE/HYPOTHESIS: To evaluate whether accuracy estimates, abstract conclusion positivity, and completeness of abstract reporting are associated with acceptance to radiology conferences and journals. STUDY TYPE: Meta-research. POPULATION: Abstracts submitted to radiology conferences (European Society of Gastrointestinal and Abdominal Radiology (ESGAR) and International Society for Magnetic Resonance in Medicine (ISMRM)) from 2008 to 2018 and manuscripts submitted to radiology journals (Radiology, Journal of Magnetic Resonance Imaging [JMRI]) from 2017 to 2018. Primary clinical studies evaluating sensitivity and specificity of a diagnostic imaging test in humans with available editorial decisions were included. ASSESSMENT: Primary variables (Youden's index [YI > 0.8 vs. <0.8], abstract conclusion positivity [positive vs. neutral/negative], number of reported items on the Standards for Reporting of Diagnostic Accuracy Studies [STARD] for Abstract guideline) and confounding variables (prospective vs. retrospective/unreported, sample size, study duration, interobserver agreement assessment, subspecialty, modality) were extracted. STATISTICAL TESTS: Multivariable logistic regression to obtain adjusted odds ratio (OR) as a measure of the association between the primary variables and acceptance by radiology conferences and journals; 95% confidence intervals (CIs) and P-values were obtained; the threshold for statistical significance was P < 0.05. RESULTS: A total of 1000 conference abstracts (500 ESGAR and 500 ISMRM) and 1000 journal manuscripts (505 Radiology and 495 JMRI) were included. Conference abstract acceptance was not significantly associated with YI (adjusted OR = 0.97 for YI > 0.8; CI = 0.70-1.35), conclusion positivity (OR = 1.21 for positive conclusions; CI = 0.75-1.90) or STARD for Abstracts adherence (OR = 0.96 per unit increase in reported items; CI = 0.82-1.18). Manuscripts with positive abstract conclusions were less likely to be accepted by radiology journals (OR = 0.45; CI = 0.24-0.86), while YI (OR = 0.85; CI = 0.56-1.29) and STARD for Abstracts adherence (OR = 1.06; CI = 0.87-1.30) showed no significant association. Positive conclusions were present in 86.7% of submitted conference abstracts and 90.2% of journal manuscripts. DATA CONCLUSION: Diagnostic test accuracy studies with positive findings were not preferentially accepted by the evaluated radiology conferences or journals. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.

Tweeting Bias in Diagnostic Test Accuracy Research: Does Title or Conclusion Positivity Influence Dissemination?

PURPOSE: To examine if tweeting bias exists within imaging literature by determining if diagnostic test accuracy (DTA) studies with positive titles or conclusions are tweeted more than non-positive studies. METHODS: DTA studies published between October 2011 to April 2016 were included. Positivity of titles and conclusions were assessed independently and in duplicate, with disagreements resolved by consensus. A negative binomial regression analysis controlling for confounding variables was performed to assess the relationship between title or conclusion positivity and tweets an article received in the 100 days post-publication. RESULTS: 354 DTA studies were included. Twenty-four (7%) titles and 300 (85%) conclusions were positive (or positive with qualifier); 1 (0.3%) title and 23 (7%) conclusions were negative; and 329 (93%) titles and 26 (7%) conclusions were neutral. Studies with positive, negative, and neutral titles received a mean of 0.38, 0.00, and 0.45 tweets per study; while those with positive, negative, and neutral conclusions received a mean of 0.44, 0.61, and 0.38 tweets per study. Regression coefficients were -0.05 (SE 0.46) for positive relative to non-positive titles, and -0.09 (SE 0.31) for positive relative to non-positive conclusions. The positivity of the title (P = 0.91) or conclusion (P = 0.76) was not significantly associated with the number of tweets an article received. CONCLUSIONS: The positivity of the title or conclusion for DTA studies does not influence the amount of tweets it receives suggesting that tweet bias is not present among imaging diagnostic accuracy studies. Study protocol available at https://osf.io/hdk2m/.

Reporting Bias in Imaging Diagnostic Test Accuracy Studies: Are Studies With Positive Conclusions or Titles Submitted and Published Faster?

OBJECTIVE: The purpose of this study is to evaluate whether imaging diagnostic test accuracy (DTA) studies with positive conclusions or titles have a shorter time to publication than those with nonpositive (i.e., negative or neutral) conclusions or titles. MATERIALS AND METHODS: We included primary imaging DTA studies from systematic reviews published in 2015. The conclusion and title of each study were extracted, and their positivity was classified independently in duplicate. The time from study completion to publication was extracted and calculated. A Cox regression model was used to evaluate associations of conclusion and title positivity with time to publication, with adjustment made for potentially confounding variables. RESULTS: A total of 774 imaging DTA studies were included; time from study completion to publication could be calculated for 516 studies. The median time from completion to publication was 18 months (interquartile range, 13-26 months) for the 413 studies with positive conclusions, 23 months (interquartile range, 16-33 months) for the 63 studies with neutral conclusions, and 25 months (interquartile range, 15-38 months) for the 40 studies with negative conclusions. A positive conclusion was associated with a shorter time from study completion to publication compared with a non-positive conclusion (hazard ratio, 1.31; 95% CI, 1.02-1.68). Of all included studies, 39 (5%) had positive titles, 731 (94%) had neutral titles, and 4 (< 1%) had negative titles. Positive titles were not significantly associated with a shorter time to study publication (hazard ratio, 1.12; 95% CI, 0.75-1.69). CONCLUSION: Positive conclusions (but not titles) were associated with a shorter time from study completion to publication. This finding may contribute to an overrepresentation of positive results in the imaging DTA literature.

Digital breast tomosynthesis for breast cancer detection: a diagnostic test accuracy systematic review and meta-analysis.

OBJECTIVES: No consensus exists on digital breast tomosynthesis (DBT) utilization for breast cancer detection. We performed a diagnostic test accuracy systematic review and meta-analysis comparing DBT, combined DBT and digital mammography (DM), and DM alone for breast cancer detection in average-risk women. METHODS: MEDLINE and EMBASE were searched until September 2018. Comparative design studies reporting on the diagnostic accuracy of DBT and/or DM for breast cancer detection were included. Demographic, methodologic, and diagnostic accuracy data were extracted. Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool. Accuracy metrics were pooled using bivariate random-effects meta-analysis. The impact of multiple covariates was assessed using meta-regression. PROSPERO ID: CRD 42018111287. RESULTS: Thirty-eight studies reporting on 488,099 patients (13,923 with breast cancer) were included. Eleven studies were at low risk of bias. DBT alone, combined DBT and DM, and DM alone demonstrated sensitivities of 88% (95% confidence interval [CI] 83-92), 88% (CI 83-92), and 79% (CI 75-82), as well as specificities of 84% (CI 76-89), 81% (CI 73-88), and 79% (CI 71-85), respectively. The greater sensitivities of DBT alone and combined DBT and DM compared to DM alone were preserved in the combined meta-regression models accounting for other covariates (p = 0.003-0.006). No significant difference in diagnostic accuracy between DBT alone and combined DBT and DM was identified (p = 0.175-0.581). CONCLUSIONS: DBT is more sensitive than DM, while the addition of DM to DBT provides no additional diagnostic benefit. Consideration of these findings in breast cancer imaging guidelines is recommended. KEY POINTS: • Digital breast tomosynthesis with or without additional digital mammography is more sensitive in detecting breast cancer than digital mammography alone in women at average risk for breast cancer. • The addition of digital mammography to digital breast tomosynthesis provides no additional diagnostic benefit in detecting breast cancer compared to digital breast tomosynthesis alone. • The specificity of digital breast tomosynthesis with or without additional digital mammography is no different than digital mammography alone in the detection of breast cancer.

Citation bias in imaging research: are studies with higher diagnostic accuracy estimates cited more often?

OBJECTIVES: To assess the risk of citation bias in imaging diagnostic accuracy research by evaluating whether studies with higher accuracy estimates are cited more frequently than those with lower accuracy estimates. METHODS: We searched Medline for diagnostic accuracy meta-analyses published in imaging journals from January 2005 to April 2016. Primary studies from the meta-analyses were screened; those assessing the diagnostic accuracy of an imaging test and reporting sensitivity and specificity were eligible for inclusion. Studies not indexed in Web of Science, duplicates, and inaccessible articles were excluded. Topic (modality/subspecialty), study design, sample size, journal impact factor, publication date, times cited, sensitivity, and specificity were extracted for each study. Negative binomial regression was performed to evaluate the association of citation rate (times cited per month since publication) with Youden's index (sensitivity + specificity -1), highest sensitivity, and highest specificity, controlling for the potential confounding effects of modality, subspecialty, impact factor, study design, sample size, and source meta-analysis. RESULTS: There were 1016 primary studies included. A positive association between Youden's index and citation rate was present, with a regression coefficient of 0.33 (p = 0.016). The regression coefficient for sensitivity was 0.41 (p = 0.034), and for specificity, 0.32 (p = 0.15). CONCLUSION: A positive association exists between diagnostic accuracy estimates and citation rates, indicating that there is evidence of citation bias in imaging diagnostic accuracy literature. Overestimation of imaging test accuracy may contribute to patient harm from incorrect interpretation of test results. KEY POINTS: • Studies with higher accuracy estimates may be cited more frequently than those with lower accuracy estimates. • This citation bias could lead clinicians, reviews, and clinical practice guidelines to overestimate the accuracy of imaging tests, contributing to patient harm from incorrect interpretation of test results.