Figures & data
Table 1 The literature quality evaluation of AHRQ
Table 2 Information from 22 studies included in the analysis
Table 3 A summary of patient characteristics among those with level IIb metastases
Table 4 Special information about the tongue squamous cell carcinoma
Figure 2 Forest plot for cervical level IIb metastasis rate for OSCC.
Abbreviations: df, degrees of freedom; IV, inverse variance; OSCC, oral squamous cell carcinoma; RD, risk difference; SE, standard error.
![Figure 2 Forest plot for cervical level IIb metastasis rate for OSCC.](/cms/asset/ac5075e9-32c1-4a45-92f1-49d106bf8f69/dott_a_12195656_f0002_b.jpg)
Figure 3 Funnel plot for cervical level IIb metastasis rate for OSCC.
Abbreviations: OSCC, oral squamous cell carcinoma; RD, risk difference.
![Figure 3 Funnel plot for cervical level IIb metastasis rate for OSCC.](/cms/asset/86a8b9a3-ab6d-4251-948c-da236cf9aae9/dott_a_12195656_f0003_b.jpg)
Figure 4 Forest plot for cervical level IIb metastasis rate for tongue SCC.
Abbreviations: df, degrees of freedom; IV, inverse variance; SCC, squamous cell carcinoma; RD, risk difference; SE, standard error.
![Figure 4 Forest plot for cervical level IIb metastasis rate for tongue SCC.](/cms/asset/729c8aed-10ee-4696-9e3c-af996dbb3e97/dott_a_12195656_f0004_c.jpg)
Figure 5 Funnel plot for cervical level IIb metastasis rate for tongue SCC.
Abbreviations: RD, risk difference; SCC, squamous cell carcinoma; SE, standard error.
![Figure 5 Funnel plot for cervical level IIb metastasis rate for tongue SCC.](/cms/asset/0b52cc46-2ff4-4783-834e-c21a1d5edcd1/dott_a_12195656_f0005_b.jpg)