Table 1

Range of serum bilirubin values (in μmol/l) used as threshold values for phototherapy, by each week of gestation between 23 and 36 weeks

Week of gestation	23	24	25	26	27	28	29	30	31	32	33	34	35	36
Number of observations	36	50	51	54	56	76	74	78	83	69	70	103	80	86
Minimum	100	80	80	80	80	80	80	100	100	150	150	150	200	200
25th percentile	120	90	100	100	115	100	150	150	160	200	200	220	250	250
Median	150	147	150	150	160	160	170	165	200	220	235	250	250	250
75th percentile	250	190	180	175	175	180	200	200	240	250	250	270	270	280
Maximum	330	330	330	330	330	330	330	330	330	330	33	370	370	380
Mean	181	155	155	155	163	156	175	176	198	224	226	240	262	269
Standard deviation	69	72	72	70	67	63	55	53	45	45	45	43	35	39
Lower 95%	158	134	135	137	146	142	163	164	188	213	215	231	255	261
Upper 95%	205	176	175	175	182	171	189	189	208	235	237	248	271	278