Temporal Trends in the Impact Factor of Common Medical Journals Between 2001 and 2008.

<p>Significant increase over time denoted by (↑), while significant decrease is denoted (↓).</p>§<p>n/a  =  not available.</p

Journal Rankings Based On Their 2008 Eigenfactor, Impact Factor and the Article Influence Score.

<p>Data presented as value (column rank).</p

The Relationship of Changes in Citable Items Between 2001 and 2008 to Changes in Eigenfactor Score and Impact Factor Between 2001 and 2008.

<p>R² = 0.1957; p = 0.0099 for the relationship between changes in citable items and changes in Eigenfactor score and R² = 0.1216; p = 0.0505* for the relationship between changes in citable items and changes in the impact factor. *The <i>New England Journal of Medicine</i> was excluded from the regression analysis, as it was an extreme outlier.</p

Temporal Trends in Citable Items of Common Medical Journals Between 2001 and 2008.

§<p>n/a  =  not available.</p><p>Significant increase over time denoted by (↑), while significant decrease is denoted (↓).</p

Temporal Trends in Article Influence Scores of Common Medical Journals Between 2001 and 2008.

§<p>n/a  =  not available.</p><p>Significant increase over time denoted by (↑), while significant decrease is denoted (↓).</p

Temporal Trends in Eigenfactor Score of Common Medical Journals Between 2001 and 2008.

§<p>n/a  =  not available.</p><p>Significant increase over time denoted by (↑), while significant decrease is denoted (↓).</p

The Relationship Between Impact Factor (IF) and Eigenvalue Score (ES) In 2008.

<p>The area of the circles is proportional to the number of citable items published in 2008. The area of the dotted line is expanded in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0010204#pone-0010204-g001" target="_blank">figure 1B</a>. R² = 0.5721; p<0.0001.</p

Selected publications from the review with Biomarker ROC analysis performance.

<p>Selected publications from the review with Biomarker ROC analysis performance.</p

A Systematic Review of Diagnostic Biomarkers of COPD Exacerbation

<div><p>The aims of this systematic review were to determine which blood-based molecules have been evaluated as possible biomarkers to diagnose chronic obstructive pulmonary disease (COPD) exacerbations (AECOPD) and to ascertain the quality of these biomarker publications. Patients of interest were those that have been diagnosed with COPD. MEDLINE, EMBASE, and CINAHL databases were searched systematically through February 2015 for publications relating to AECOPD diagnostic biomarkers. We used a modified guideline for the REporting of tumor MARKer Studies (mREMARK) to assess study quality. Additional components of quality included the reporting of findings in a replication cohort and the use of receiver-operating characteristics area-under-the curve statistics in evaluating performance. 59 studies were included, in which the most studied biomarkers were C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). CRP showed consistent elevations in AECOPD compared to control subjects, while IL-6 and TNF-α had variable statistical significance and results. mREMARK scores ranged from 6 to 18 (median score of 13). 12 articles reported ROC analyses and only one study employed a replication cohort to confirm biomarker performance. Studies of AECOPD diagnostic biomarkers remain inconsistent in their reporting, with few studies employing ROC analyses and even fewer demonstrating replication in independent cohorts.</p></div

PRISMA flow diagram of study screening and selection.

<p>PRISMA flow diagram used in study selection and screening. 59 studies were included for review whereas the rest of the studies were excluded.</p