Table 2. Factors associated with inadequate dosing of rifampin among patients treated with Rifater, Rifinah, or Rifampicin in single-drug preparation, 2007–2010, Taipei.

	Adequate	Too high		Too low
	Number (%)	Relative RR	95% CI	Relative RR	95% CI
Weight (kg)
≤39	63(45.0%)	1		1
40–49	576(72.8%)	0.25	0.17–0.37	0.30	0.08–1.07
≥50	1932(97.3%)	0.0002	0.00002–0.001	1.19	0.38–3.72
Preparations
Rifampicin	459(83.0%)	1		1
Rifater	1663(89.9%)	0.99	0.69–1.41	0.21	0.12–0.37
Rifinah150	102(77.9%)	0.46	0.25–0.85	2.21	0.97–5.01
Rifinah300	347(90.4%)	8.85	4.29–18.25	0.04	0.005–0.27

Adequate dosage (8–12 mg/kg) as the base for comparison. Too high, >12 mg/kg. Too low, <8 mg/kg. RR, risk ratio. CI, confidence interval.