Table 3.
Changes in healthcare service usage and costs from before to after the operation
| Variables | Before operation | After operation | Comparison between means of paired samples | ||
|---|---|---|---|---|---|
| Mean number | Mean number | Difference between means (before/after) | 95% CI | P value | |
| Elective consultation | |||||
| Whole year | 12.1 | 9.5 | 2.64 | 2.16 to 3.11 | < 0.001 |
| Partial year | 6.1 | 6.9 | −0.82 | −1.27 to 0.38 | < 0.001 |
| Emergency consultation | |||||
| Whole year | 1.3 | 1.2 | 0.05 | −0.15 to 0.26 | 0.594 |
| Partial year | 0.9 | 0.9 | > 0.01 | −0.16 to 0.17 | 0.975 |
| Laboratory tests | |||||
| Whole year | 33.5 | 31.0 | 2.46 | 0.10 to 5.03 | 0.059 |
| Partial year | 13.9 | 24.2 | −10.3 | −12.4 to −8.17 | < 0.001 |
| Imaging examinations | |||||
| Whole year | 3.7 | 2.0 | 1.76 | 1.47 to 2.06 | < 0.001 |
| Partial year | 1.8 | 1.5 | 0.24 | −0.001 to 0.49 | 0.051 |
| Costs (US$) for all 382 patients | Mean cost | Mean cost | Difference between mean costs | 95% CI | P value |
| Whole year | 756.94 | 896.23 | −139.29 | −375.19 to 96.61 | 0.246 |
| Partial year | 391.96 | 678.31 | −286.35 | −473.28 to −99.42 | 0.003 |
| Costs (US$) for 43 patients who underwent gastrointestinal tract procedure or had complications related to bariatric surgery procedure | |||||
| Whole year | 784.01 | 2,897.20 | −2,113.18 | −3,767.58 to −458.79 | 0.014 |
| Partial year | 460.03 | 1,979.59 | −1,519.56 | −2,824.27 to −214.85 | 0.024 |
| Costs (US$) for the other 339 patients without intervention or with other interventions | |||||
| Whole year | 687.80 | 554.82 | 132.97 | 27.75 to 238.20 | 0.013 |
| Partial year | 355.00 | 448.00 | −92.98 | −185.86 to −0.09 | 0.05 |
CI = confidence interval; US$ = United States dollars.
Whole year: measurement considering four three-month periods both before and after surgery; Partial year: measurement excluding the three-month periods immediately before and after the surgery.