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. 2019 Jan 28;10(2):225–239. doi: 10.1002/jrsm.1336

Table 1.

Average and standard deviation (in parentheses) of the confidence interval width of the Q‐profile method, GENQ method with variance weights ( ai=1/σ^i2), and GENQ method with standard error weights (SE; ai=1/σ^i)

πiC=0.5
τ = 0 τ = 0.1 τ = 0.2 τ = 0.3 τ = 0.4 τ = 0.5
k = 5 Q‐profile 0.830 (0.392) 0.870 (0.398) 0.980 (0.405) 1.121 (0.433) 1.280 (0.454) 1.449 (0.501)
GENQ (variance) 0.747 (0.308) 0.797 (0.321) 0.934 (0.355) 1.103 (0.402) 1.290 (0.450) 1.478 (0.512)
GENQ (SE) 0.775 (0.332) 0.817 (0.340) 0.942 (0.359) 1.097 (0.393) 1.267 (0.416) 1.438 (0.460)
k = 10 Q‐profile 0.461 (0.188) 0.490 (0.186) 0.564 (0.175) 0.641 (0.161) 0.710 (0.155) 0.786 (0.166)
GENQ (variance) 0.404 (0.141) 0.440 (0.144) 0.531 (0.142) 0.623 (0.134) 0.709 (0.139) 0.802 (0.167)
GENQ (SE) 0.435 (0.156) 0.465 (0.156) 0.546 (0.152) 0.636 (0.136) 0.709 (0.120) 0.783 (0.127)
k = 40 Q‐profile 0.221 (0.075) 0.251 (0.068) 0.285 (0.040) 0.282 (0.029) 0.299 (0.030) 0.327 (0.034)
GENQ (variance) 0.199 (0.059) 0.230 (0.054) 0.267 (0.027) 0.269 (0.015) 0.294 (0.026) 0.332 (0.035)
GENQ (SE) 0.227 (0.069) 0.255 (0.064) 0.3 (0.041) 0.295 (0.023) 0.295 (0.015) 0.318 (0.024)
k = 80 Q‐profile 0.167 (0.052) 0.198 (0.043) 0.201 (0.022) 0.191 (0.014) 0.205 (0.015) 0.225 (0.017)
GENQ (variance) 0.154 (0.043) 0.185 (0.036) 0.187 (0.019) 0.181 (0.007) 0.201 (0.013) 0.228 (0.017)
GENQ (SE) 0.180 (0.051) 0.207 (0.045) 0.226 (0.029) 0.196 (0.011) 0.200 (0.007) 0.218 (0.012)
k = 160 Q‐profile 0.130 (0.039) 0.161 (0.027) 0.137 (0.011) 0.133 (0.007) 0.143 (0.007) 0.157 (0.008)
GENQ (variance) 0.122 (0.034) 0.153 (0.024) 0.126 (0.010) 0.125 (0.003) 0.140 (0.006) 0.159 (0.009)
GENQ (SE) 0.145 (0.040) 0.174 (0.032) 0.158 (0.024) 0.134 (0.002) 0.139 (0.004) 0.152 (0.006)
πiC=0.1
τ = 0 τ = 0.1 τ = 0.2 τ = 0.3 τ = 0.4 τ = 0.5
k = 5 Q‐profile 1.399 (0.712) 1.412 (0.714) 1.488 (0.728) 1.587 (0.751) 1.732 (0.759) 1.889 (0.793)
GENQ (variance) 1.201 (0.500) 1.233 (0.518) 1.315 (0.537) 1.449 (0.589) 1.614 (0.627) 1.791 (0.682)
GENQ (SE) 1.276 (0.559) 1.297 (0.569) 1.372 (0.581) 1.486 (0.618) 1.639 (0.641) 1.807 (0.682)
k = 10 Q‐profile 0.734 (0.311) 0.760 (0.314) 0.814 (0.317) 0.899 (0.316) 0.981 (0.306) 1.067 (0.306)
GENQ (variance) 0.626 (0.223) 0.655 (0.23) 0.718 (0.239) 0.814 (0.247) 0.912 (0.243) 1.005 (0.241)
GENQ (SE) 0.696 (0.256) 0.722 (0.259) 0.774 (0.264) 0.862 (0.272) 0.955 (0.266) 1.051 (0.262)
k = 40 Q‐profile 0.317 (0.113) 0.337 (0.114) 0.395 (0.11) 0.455 (0.087) 0.474 (0.065) 0.477 (0.055)
GENQ (variance) 0.289 (0.094) 0.310 (0.096) 0.37 (0.093) 0.429 (0.069) 0.447 (0.042) 0.448 (0.028)
GENQ (SE) 0.348 (0.111) 0.365 (0.111) 0.417 (0.109) 0.485 (0.094) 0.526 (0.071) 0.525 (0.053)
k = 80 Q‐profile 0.223 (0.082) 0.246 (0.082) 0.307 (0.075) 0.347 (0.047) 0.330 (0.035) 0.321 (0.026)
GENQ (variance) 0.210 (0.073) 0.233 (0.072) 0.295 (0.066) 0.332 (0.041) 0.309 (0.028) 0.299 (0.013)
GENQ (SE) 0.263 (0.085) 0.282 (0.084) 0.336 (0.08) 0.396 (0.059) 0.395 (0.049) 0.354 (0.036)
k = 160 Q‐profile 0.160 (0.060) 0.183 (0.061) 0.249 (0.050) 0.256 (0.032) 0.223 (0.016) 0.221 (0.012)
GENQ (variance) 0.154 (0.055) 0.178 (0.056) 0.243 (0.046) 0.245 (0.034) 0.207 (0.012) 0.205 (0.005)
GENQ (SE) 0.199 (0.067) 0.219 (0.067) 0.279 (0.059) 0.322 (0.042) 0.271 (0.039) 0.237 (0.012)

Abbreviation: GENQ, generalized Q‐statistic.

The probability of having the outcome of interest in the control group is denoted by πiC, the number of primary studies in a meta‐analysis with k, and the amount of between‐study heterogeneity with τ.