Table 3. Factors associated with inadequate dosing of isoniazid among patients treated with Rifater, Rifinah or isoniazid in single-drug preparation, 2007–2010, Taipei.

	Adequate	Too high		Too low
	Number (%)	Relative RR	95% CI	Relative RR	95% CI
Weight (kg)
≤39	19(13.3%)	1		1
40–49	58(7.2%)	2.64	1.36–5.14	0.44	0.06–3.43
≥50	706(35.1%)	0.02	0.01–0.04	0.13	0.03–0.72
Preparations
Isoniazid	406(68.8%)	1		1
Rifater	5(0.3%)	12017.89	4215.91–34258.24	103.84	23.12–466.32
Rifinah150	25(19.1%)	16.93	7.62–37.60	4.91	0.94–25.54
Rifinah300	347(90.4%)	0.63	0.34–1.13	0.23	0.03–1.91

Adequate dosage (4–6 mg/kg) as the base for comparison. Too high, >6 mg/kg. Too low, <4 mg/kg. RR, risk ratio. CI, confidence interval.