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. 2024 May 16;23:48. doi: 10.1186/s12940-024-01088-w

Table 2.

Bias (SE) for exposures in Group 1 and R2 with WQS and each LOD accommodation approach compared to using full dataset

LOD accommodation Moderate correlation (σ=1/2) High correlation (σ=1/8)
ψ w1 w2 w3 R2 ψ w1 w2 w3 R2
Scenario 1
 Complete case -0.34 (0.33) -0.03 (0.10) -0.04 (0.10) 0.02 (0.06) 0.73 -0.03 (0.33) -0.02 (0.13) 0.01 (0.13) 0.01 (0.10) 0.87
 LOD/2 0.15 (0.22) -0.02 (0.06) 0.00 (0.08) 0.01 (0.05) 0.86 0.01 (0.26) 0.00 (0.13) -0.02 (0.11) 0.00 (0.10) 0.92
 MI -0.06 (0.18) 0.03 (0.06) -0.05 (0.06) 0.00 (0.04) 0.79 0.01 (0.24) 0.00 (0.13) 0.00 (0.11) 0.00 (0.09) 0.93
 Truncated MI 0.00 (0.18) 0.00 (0.06) 0.00 (0.07) 0.00 (0.04) 0.84 0.01 (0.24) 0.00 (0.13) 0.00 (0.11) 0.00 (0.10) 0.93
 F-AFT -0.01 (0.18) 0.00 (0.06) 0.00 (0.07) 0.00 (0.04) 0.85 -0.01 (0.24) 0.00 (0.13) -0.01 (0.11) 0.00 (0.10) 0.93
Scenario 2A
 Complete case -0.49 (0.29) 0.08 (0.12) 0.05 (0.08) 0.54 -0.05 (0.30) 0.02 (0.14) 0.03 (0.11) 0.83
 LOD/2 -0.17 (0.19) 0.08 (0.07) 0.05 (0.07) 0.65 -0.01 (0.25) 0.03 (0.14) 0.02 (0.11) 0.88
 MI -0.28 (0.17) 0.11 (0.07) 0.02 (0.05) 0.63 -0.01 (0.23) 0.03 (0.14) 0.02 (0.10) 0.90
 Truncated MI -0.28 (0.17) 0.12 (0.07) 0.03 (0.05) 0.63 -0.01 (0.23) 0.04 (0.14) 0.02 (0.11) 0.90
 F-AFT -0.28 (0.17) 0.11 (0.07) 0.04 (0.06) 0.65 -0.02 (0.23) 0.04 (0.14) 0.02 (0.12) 0.90
Scenario 2B
 Complete case -0.33 (0.34) -0.14 (0.04) -0.20 (0.05) 0.04 (0.07) 0.45 -0.01 (0.34) -0.06 (0.04) -0.06 (0.08) 0.01 (0.10) 0.82
 LOD/2 0.09 (0.22) -0.11 (0.04) -0.22 (0.03) 0.04 (0.06) 0.57 0.04 (0.29) -0.06 (0.05) -0.07 (0.07) 0.01 (0.11) 0.88
 MI -0.10 (0.19) -0.15 (0.02) -0.21 (0.03) 0.01 (0.04) 0.50 0.03 (0.25) -0.08 (0.01) -0.07 (0.07) 0.01 (0.09) 0.89
 Truncated MI -0.12 (0.19) -0.15 (0.02) -0.21 (0.03) 0.02 (0.05) 0.50 0.03 (0.26) -0.08 (0.01) -0.07 (0.07) 0.01 (0.10) 0.89
 F-AFT -0.12 (0.19) -0.16 (0.02) -0.21 (0.03) 0.03 (0.05) 0.52 0.01 (0.26) -0.08 (0.01) -0.07 (0.08) 0.01 (0.10) 0.89
Scenario 3
 Complete case -0.46 (0.35) 0.00 (0.10) -0.11 (0.10) 0.03 (0.06) 0.69 -0.54 (0.44) -0.03 (0.11) -0.12 (0.11) 0.04 (0.07) 0.66
 LOD/2 0.16 (0.23) -0.01 (0.06) -0.01 (0.08) 0.01 (0.04) 0.85 0.20 (0.24) -0.02 (0.06) 0.01 (0.07) 0.01 (0.04) 0.86
 MI -0.14 (0.20) 0.05 (0.07) -0.10 (0.07) 0.01 (0.04) 0.75 -0.14 (0.21) 0.05 (0.07) -0.10 (0.07) 0.01 (0.04) 0.74
 Truncated MI 0.03 (0.19) -0.01 (0.06) 0.01 (0.07) 0.00 (0.04) 0.83 0.05 (0.19) -0.01 (0.06) 0.02 (0.07) 0.00 (0.04) 0.83
 F-AFT 0.01 (0.20) 0.00 (0.06) 0.00 (0.07) 0.00 (0.04) 0.84 0.01 (0.20) 0.00 (0.06) 0.00 (0.07) 0.00 (0.04) 0.84
Scenario 4
 Complete case -0.35 (0.34) -0.02 (0.11) -0.06 (0.10) 0.03 (0.06) 0.72 -0.45 (0.42) -0.05 (0.11) -0.08 (0.10) 0.04 (0.07) 0.69
 LOD/2 0.18 (0.22) -0.02 (0.06) 0.01 (0.08) 0.01 (0.04) 0.86 0.20 (0.22) -0.03 (0.06) 0.02 (0.08) 0.01 (0.04) 0.87
 MI -0.08 (0.18) 0.03 (0.07) -0.07 (0.07) 0.00 (0.04) 0.78 -0.08 (0.18) 0.04 (0.07) -0.07 (0.06) 0.00 (0.04) 0.76
 Truncated MI 0.02 (0.17) 0.00 (0.07) 0.01 (0.07) 0.00 (0.04) 0.84 0.03 (0.18) -0.01 (0.06) 0.02 (0.07) 0.00 (0.04) 0.84
 F-AFT 0.00 (0.18) 0.00 (0.07) 0.00 (0.07) 0.00 (0.04) 0.85 0.00 (0.18) 0.00 (0.07) 0.00 (0.07) 0.00 (0.04) 0.85

Bias (SE) was reported for the total effect (ψ) and exposures in group 1 (w1,w2 and w3). All other results are provided in Table S2. All comparisons were made to the parameters with full datasets without LOD. R2 was calculated by regression h^ from each LOD accommodation on h^ with the full dataset. In Scenario 2A, w2 was not estimated because Z2 was not included in the analysis

Abbreviations: Imputation by LOD/2 (LOD/2), MI Conventional multiple imputation, Truncated MI Truncated multiple imputation, F-AFT Imputation by estimates using the AFT model