The review addressed a clearly stated question, defined by appropriate inclusion criteria. The search strategy was limited to one bibliographic database and a review of the references of included studies, making the analysis vulnerable to the omission of relevant data. This problem was compounded by restriction to published English language studies, leaving open the possibility of both language and publication biases. No assessment of the methodological quality of included studies was reported. No methods to minimise error and/or bias were reported for the review process. Therefore, the vulnerability of the review to error and/or bias introduced by poor quality studies or in the review process cannot be assessed.
The results of the heterogeneity assessment, for studies included in the meta-analyses, were not reported. Simple pooling of sensitivity across heterogeneous studies is not generally recommended and the pooled estimates presented may be of limited value. The authors did not define sentinel lymph node detection rate the main result reported. As highlighted by the authors, the absence of data on the false negative rates of these tests was a significant factor hindering interpretation of their clinical value.
Given the limitations described, the authors' conclusion that sentinel lymph node biopsy using 99mTc colloid tracers demonstrated a higher detection rate than techniques using blue dyes, in patients with thyroid carcinoma, should be interpreted with considerable caution.