Table 3 Results of subgroup analyses
| Â | Number of studies | Identification rate (95% CI) | P | Sensitivity (95% CI) | P |
|---|---|---|---|---|---|
Preoperative T stage | |||||
 cT1 | 12 | 0.979 (0.923–1.035) | 0.00 | 0.861 (0.786–0.917) | 0.22 |
 cT2 | 2 | 0.963 (0.751–1.176) | 0.00 | 0.943 (0.808–0.993) | 0.51 |
Number of SLNs | |||||
 <5 | 11 | – | – | 0.839 (0.760–0.900) | 0.07 |
 ≥5 | 8 | – | – | 0.944 (0.882–0.979) | 0.84 |
Method of SLN biopsy | |||||
 Pick up | 13 | 0.973 (0.959–0.988) | 0.01 | 0.869 (0.810–0.915) | 0.11 |
 Basin dissection | 6 | 0.949 (0.925–0.974) | 0.66 | 0.959 (0.860–0.995) | 0.39 |
Type of dual tracers | |||||
  99mTc tin colloid + isosulfan blue | 3 | 0.971 (0.960–0.982) | 0.77 | 0.884 (0.810–0.937) | 0.07 |
  99mTc tin colloid + ICG | 3 | 0.889 (0.779–1.000) | <.001 | 0.826 (0.612–0.950) | 0.34 |
  99mTc tin colloid + patent blue violet | 5 | 0.962 (0.933–0.992) | 0.93 | 0.880 (0.688–0.975) | 0.31 |
  99mTc-HSA + ICG | 2 | 0.932 (0.890–0.977) | 0.62 | 1.00 (0.735–1.000) | >0.99 |
  99mTc-antimony sulfur colloid + ICG | 2 | 0.932 (0.882–0.985) | 0.38 | 1.00 (0.846–1.000) | >0.99 |
Time performing SLN biopsy after dye injection | |||||
 ≥15 min | 9 | 0.973 (0.958–0.989) | 0.10 | 0.952 (0.898–0.982) | 0.71 |
 <15 min | 10 | 0.962 (0.939–0.986) | 0.03 | 0.810 (0.719–0.882) | 0.33 |
Method for intraoperative histological evaluation of SLN | |||||
 HE | 7 | – | – | 0.908 (0.849–0.950) | 0.11 |
 HE + IHC | 8 | – | – | 0.864 (0.750–0.940) | 0.08 |
Methods of surgery | |||||
 Opening surgery | 7 | 0.976 (0.965–0.988) | >.99 | 0.867 (0.786–0.925) | 0.06 |
 Laparoscopic surgery | 10 | 0.939 (0.907–0.972) | 0.04 | 0.909 (0.813–0.969) | 0.13 |
Country | |||||
 Japan | 12 | 0.980 (0.973–0.988) | 0.54 | 0.896 (0.837–0.939) | 0.31 |
 Not in Japan | 7 | 0.934 (0.891–0.978) | 0.01 | 0.873 (0.773–0.940) | 0.03 |
Year of studies | |||||
 ≥2013 | 7 | 0.976 (0.963–0.990) | 0.06 | 0.905 (0.843–0.949) | 0.15 |
 <2013 | 12 | 0.955 (0.931–0.980) | 0.07 | 0.864 (0.774–0.928) | 0.11 |