TABLE 1.

Probability of target attainment for guidelines and Swiss centers for effective peak concentrations (≥5 or ≥10 mg/liter) and trough concentrations (>2 mg/liter)^a

Guidelineb	Demographic characteristics	Dose (mg/kg)	Interval (h)	No. of subgroupsc	Targets (mg/liter)
					Peak (%)		Trough (%) (>2)
					≥5	≥10
No demographic variable
Center 5		4	24	1	96	26	4
Center 7c
1		5	24	1	99	54	12
2		5	36	1	99	54	<0.5
3		5	48	1	99	54	<0.5
One demographic variable
BNFc	PNA	5	24/36	2	99	54	3
Blue Book (min)	GA	4	24/36	2	96	26	1
Blue Book (max)	GA	5	24/36	2	99	54	4
Two demographic variables
Center 1	PNA, wt	4/5	24–48	5	97	39	2
Center 2	PNA, wt	5/6	24–48	7	99	58	4
Center 3 (min)	PNA, GA	4/5	24–48	6	96	28	1
Center 3 (max)	PNA, GA	5	24–48	6	99	54	4
Center 4	PNA, PMA	4/4.5/5	24–48	6	96	30	2
Center 6	PNA, GA	4/4.5/5	24–48	6	96	30	1
Nelson	PNA, GA	4/4.5/5	24–48	7	97	37	1
NNF7	PNA, GA	5	24–48	4	99	55	5
Lexicomp	PNA, GA	4/4.5/5	24–48	6	98	43	1
Red Book (min)	PNA, wt	4/5	24–48	6	97	39	2
Red Book (max)	PNA, wt	4/5	24–48	6	98	44	2
Neofax	PNA, PMA	4/4.5/5	24–48	5	96	30	1
Shann	PNA, wt	5/6	24–48	7	99	58	4

^aAbbreviations: BNFc, British National Formulary for Children; Blue Book, Manual of Childhood Infections Blue Book; Nelson, Nelson Textbook of Pediatrics; NNF7, Neonatal Formulary, 7th ed.; Lexicomp, Lexicomp Pediatric and Neonatal Dosage Handbook; Red Book, The Red Book Report of the Committee on Infectious Diseases; Shann, Drug Doses (Frank Shann) PNA, postnatal age; GA, gestational age; wt; weight; PMA, postmenstrual age. Slashes (/) between numbers indicate “or.”

^bThe guidelines suggested a dosing interval range of 24 to 48 h, and therapeutic drug monitoring was recommended after the first dose.

^cSubgroups are based on demographic characteristics, as indicated in the guidelines.