Evidence-Based Complementary and Alternative Medicine / 2015 / Article / Tab 3

Research Article

Effect of Japanese Herbal Kampo Medicine Goreisan on Reoperation Rates after Burr-Hole Surgery for Chronic Subdural Hematoma: Analysis of a National Inpatient Database

Table 3

Relative risks, risk differences, and number needed to treat in reoperation rates comparing Goreisan users with nonusers.

Relative riskRisk differenceNumber needed to treat
(95% CI)(95% CI)(95% CI)

Propensity-score matching (,758)0.78 (0.64; 0.93)−1.4% (−2.4%; −0.38%)72 (41; 265)
Instrumental-variable analysis (,836)−2.2% (−3.8%; −0.67%)45 (26; 148)

CI, confidence interval.

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