This diagnostic review addressed a relevant research question using appropriate inclusion criteria. A suitable search was performed but only studies published in English were included so some relevant studies may have been missed. Apart from the data extraction, it was unclear whether action was taken to avoid reviewer error and bias. Study quality was assessed and appeared to be moderate to good in most studies but it was not clear that tests were performed blind to patient characteristics. All studies were observational in nature and may have been affected by confounding or other biases.
Estimates of diagnostic performance were pooled in meta-analyses but the correlation between sensitivity and specificity, and between other measures was not accounted for and this may have produced misleading results. Only one threshold of plasma D-dimer (500ng/mL, based on its use in identifying pulmonary emboli rather than acute aortic dissection) was used; it was unclear whether other thresholds might give more favourable results. The number of participants was small. The considerable diversity in the clinical conditions across studies was reflected in high heterogeneity across studies in some analyses.
The results and the authors' conclusions are reasonable given the evidence available but some caution is needed when interpreting the results due to the limited sample size and clinical diversity.