Table 3.
Results of Pooled Analyses for Cancer Sites and Exposure Contrasts Examined in More than One Study. DerSimonian and Laird Random Effects Model and Fixed Effects Model
| Cancer Site | Exposure Contrast | Number of Populations* | Random Effects Model | Fixed Effects Model‡ | Heterogeneity† | ||
|---|---|---|---|---|---|---|---|
| RR | [95% CI] | RR | [95% CI] | p | |||
| Any | insulin vs no insulin | 4 | 1.04 | [0.75 , 1.45] | <0.001 | ||
| insulin vs niad | 2 | 1.52 | [1.16 , 2.00] | 0.043 | |||
| glargine vs non-glargine | 7 | 0.96 | [0.83 , 1.10] | <0.001 | |||
| stomach | insulin vs no insulin | 3 | 1.65 | [1.02 , 2.68] | 0.002 | ||
| insulin vs niad | 1 | na | - | - | |||
| glargine vs non-glargine | 1 | na | - | - | |||
| pancreatic | insulin vs no insulin | 8 | 2.58 | [2.05 , 3.25] | <0.001 | ||
| insulin vs niad | 3 | 3.83 | [1.43 , 10.23] | 4.37 | [2.62 , 5.67] | 0.167 | |
| glargine vs non-glargine | 3 | 1.17 | [0.78 , 1.77] | 1.12 | [0.86 , 1.46] | 0.128 | |
| Liver | insulin vs no insulin | 6 | 1.84 | [1.32 , 2.58] | <0.001 | ||
| insulin vs niad | 1 | na | - | - | |||
| glargine vs non-glargine | 2 | 0.89 | [0.64 , 1.24] | 0.88 | [0.68 , 1.14] | 0.203 | |
| kidney | insulin vs no insulin | 4 | 1.38 | [1.06 , 1.79] | 0.002 | ||
| insulin vs niad | 0 | na | - | - | |||
| glargine vs non-glargine | 1 | na | - | - | |||
| bladder | insulin vs no insulin | 5 | 1.09 | [0.93 , 1.28] | 1.07 | [0.98 , 1.17] | 0.096 |
| insulin vs niad | 0 | na | - | - | |||
| glargine vs non-glargine | 2 | 1.34 | [0.81 , 2.22] | 1.32 | [0.93 , 1.86] | 0.150 | |
| colorectal | insulin vs no insulin | 7 | 1.16 | [0.87 , 1.55] | <0.001 | ||
| insulin vs niad | 2 | 1.79 | [1.36 , 2.36] | 1.79 | [1.36 , 2.36] | 0.474 | |
| glargine vs non-glargine | 4 | 0.92 | [0.75 , 1.13] | 0.92 | [0.75 , 1.13] | 0.742 | |
| Colon | insulin vs no insulin | 5 | 1.02 | [0.92 , 1.13] | 1.02 | [0.92 , 1.13] | 0.675 |
| insulin vs niad | 1 | na | - | - | |||
| glargine vs non-glargine | 2 | 0.71 | [0.56 , 0.91] | 0.72 | [0.58 , 0.89] | 0.265 | |
| rectal | insulin vs no insulin | 6 | 1.00 | [0.85 , 1.17] | 1.00 | [0.85 , 1.17] | 0.565 |
| insulin vs niad | 0 | na | - | - | |||
| glargine vs non-glargine | 0 | na | - | - | |||
| respiratory | insulin vs no insulin | 6 | 1.30 | [1.14 , 1.47] | <0.001 | ||
| insulin vs niad | 1 | na | - | - | |||
| glargine vs non-glargine | 4 | 0.99 | [0.83 , 1.17] | 0.99 | [0.83 , 1.17] | 0.733 | |
| NHL | insulin vs no insulin | 4 | 1.16 | [0.83 , 1.62] | 0.020 | ||
| insulin vs niad | 0 | na | - | - | |||
| glargine vs non-glargine | 0 | na | - | - | |||
| melanoma | insulin vs no insulin | 3 | 0.99 | [0.80 , 1.22] | 0.99 | [0.81 , 1.20] | 0.322 |
| insulin vs niad | 0 | na | - | - | |||
| glargine vs non-glargine | 0 | na | - | - | |||
| prostate | insulin vs no insulin | 3 | 0.80 | [0.73 , 0.88] | 0.80 | [0.73 , 0.88] | 0.825 |
| insulin vs niad | 3 | 1.15 | [0.86 , 1.54] | 1.15 | [0.86 , 1.54] | 0.477 | |
| glargine vs non-glargine | 6 | 1.13 | [0.98 , 1.32] | 1.13 | [0.98 , 1.32] | 0.726 | |
| breast | insulin vs no insulin | 7 | 0.90 | [0.81 , 1.00] | 0.033 | ||
| insulin vs niad | 4 | 1.13 | [0.88 , 1.45] | 1.13 | [0.88 , 1.45] | 0.862 | |
| glargine vs non-glargine | 9 | 1.14 | [1.01 , 1.29] | 1.14 | [1.01 , 1.29] | 0.059 | |
Abbreviations: na, not applicable. NHL, non-Hodgkin's lymphoma. niad, non-insulin antidiabetic drugs. NOS, Newcastle Ottawa Scale. Underlined estimates indicate statistical significance at 5% level.
*
Some studies contribute more than one population in one analysis, e.g. if results in the original study is only presented stratified by gender.
‡
Only run for heterogeneous studies (test for heterogeneity p>0.05).
†
Chi square test for heterogeneity.