# Table 4 Mean cost differences (ΔC), mean effect differences (ΔE), incremental cost-utility ratios and distribution of the joint cost-effect pairs in the cost-utility plane from the main cost-utility analysis and corresponding three sensitivity analyses (SA1, SA2 and SA3).

Analysis* Sample size ΔC (95% CI) ΔE (95% CI) ICUR Distribution in CU-plane
STC CP     NE SE SW§ NW
Main 260 272 177 (-293; 678) -0.007 (-0.023; 0.009) -25,440 ** 10% 9% 14% 67%
SA1 260 272 186 (-350; 751) -0.007 (-0.023; 0.009) -26,774 ** 10% 9% 16% 65%
SA2 252 260 -194 (-295; 751) -0.005 (-0.021; 0.117) -42,569 ** 17% 13% 10% 59%
SA3 200 210 41 (-404; 487) 0.001 (-0.017; 0.015) -40,939 ** 20% 25% 17% 38%
1. * In the main analysis, ΔE = mean difference in QALY, ΔC = mean difference in total costs in which the productivity loss costs were estimated by the FCM; in SA1, ΔC = mean difference in total costs in which the productivity loss costs were estimated by the HCA; SA2 is a repetition of the main analysis in which women who became pregnant a second time during follow-up (N = 20) were excluded; SA3 is a repetition of the main analysis using only the complete cases.
2. Refers to the northeast quadrant of the CU-plane, which indicates that STC is more effective and more costly than CP.
3. Refers to the southeast quadrant of the CU-plane, which indicates that STC is more effective and less costly than CP.
4. § Refers to the southwest quadrant of the CU-plane, which indicates that STC is less effective and less costly than CP.
5. Refers to the northwest quadrant of the CU-plane, which indicates that STC is less effective and more costly than CP.
6. ** All of these negative incremental cost-utilty ratios (ICURs) were located in the NW quadrant, along with the majority of joint cost-effect pairs, indicating that the STC was less effective and more costly than CP.