Forest plot of the diagnostic odds ratio (dOR) of each index test in the reviewed studies.

<p>CI: confidence interval; (a), (b) and (c) indicate different subgroups of participants in that study, as defined by setting (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0154411#pone.0154411.t001" target="_blank">Table 1</a>).</p

Pooled accuracy parameters in the diagnosis of diabetic retinopathy, by index test.

<p>Values in parentheses are 95 per cent confidence intervals. FPG: fasting plasma glucose, PLR: positive likelihood ratio, NLR: negative likelihood ratio, dOR: diagnostic odds ratio, AUC: area under receiver operating characteristic curve.</p

Hierarchical summary receiver operating characteristic (HSROC) curves summarizing the ability of glycated haemoglobin (HbA1c) and fasting plasma glucose (FPG) to identify diabetes retinopathy.

<p>Hierarchical summary receiver operating characteristic (HSROC) curves summarizing the ability of glycated haemoglobin (HbA1c) and fasting plasma glucose (FPG) to identify diabetes retinopathy.</p

The Accuracy of Diagnostic Methods for Diabetic Retinopathy: A Systematic Review and Meta-Analysis

<div><p>Objective</p><p>The objective of this study was to evaluate the accuracy of the recommended glycemic measures for diagnosing diabetic retinopathy.</p><p>Methods</p><p>We systematically searched MEDLINE, EMBASE, the Cochrane Library, and the Web of Science databases from inception to July 2015 for observational studies comparing the diagnostic accuracy of glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), and 2-hour plasma glucose (2h-PG). Random effects models for the diagnostic odds ratio (dOR) value computed by Moses’ constant for a linear model and 95% CIs were used to calculate the accuracy of the test. Hierarchical summary receiver operating characteristic curves (HSROC) were used to summarize the overall test performance.</p><p>Results</p><p>Eleven published studies were included in the meta-analysis. The pooled dOR values for the diagnosis of retinopathy were 16.32 (95% CI 13.86–19.22) for HbA1c and 4.87 (95% CI 4.39–5.40) for FPG. The area under the HSROC was 0.837 (95% CI 0.781–0.892) for HbA1c and 0.735 (95% CI 0.657–0.813) for FPG. The 95% confidence region for the point that summarizes the overall test performance of the included studies occurs where the cut-offs ranged from 6.1% (43.2 mmol/mol) to 7.8% (61.7 mmol/mol) for HbA1c and from 7.8 to 9.3 mmol/L for FPG. In the four studies that provided information regarding 2h-PG, the pooled accuracy estimates for HbA1c were similar to those of 2h-PG; the overall performance for HbA1c was superior to that for FPG.</p><p>Conclusions</p><p>The three recommended tests for the diagnosis of type 2 diabetes in nonpregnant adults showed sufficient accuracy for their use in clinical settings, although the overall accuracy for the diagnosis of retinopathy was similar for HbA1c and 2h-PG, which were both more accurate than for FPG. Due to the variability and inconveniences of the glucose level-based methods, HbA1c appears to be the most appropriate method for the diagnosis diabetic retinopathy.</p></div

Literature search PRISMA consort diagram.

<p>Literature search PRISMA consort diagram.</p

Characteristics of studies included in the meta-analysis.

<p>Sens: sensitivity; Spec: specificity; AUC, area under the curve; dOR, diagnostic odds ratio; FPG, fasting plasma glucose; 2h-PG, 2 hours plasma glucose.</p

ROC curve for determining PAD by oscillometric ABI compared with Doppler.

<p>Blue line: total sample, n = 180. Green line: calcified legs are excluded; oscillometric measurement errors are included, n = 167. Red line: oscillometric measurement errors and calcified legs are excluded, n = 151. The areas under the curve were 0.914, 0.958 and 0.944 respectively, showing the DeLong´s test no statistically significant differences between them.</p

Correlation and level of agreement in the pressures of arm, ankle and ABI for Doppler and oscillometer.

<p>Correlation and level of agreement in the pressures of arm, ankle and ABI for Doppler and oscillometer.</p

Characteristics of participants by place of origin.

<p>Characteristics of participants by place of origin.</p

Flow chart of the study.

<p>Study design, number of participants and results of the measurements according to STARD [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0167408#pone.0167408.ref016" target="_blank">16</a>] standards.</p