Table 3

Subgroup analysis of outcomes at the 18-month medical check-up

Subgroup	DQ18 scores							Distribution of developmental levels*
	OLB6378 administration		Placebo administration		Mean difference	95% CI	P value†	OLB6378 administration		Placebo administration		Partial correlation coefficient	95% CI	P value‡
	n	Mean±SD	n	Mean±SD	Mean difference	95% CI	P value†	n	Mean ± SD	n	Mean ± SD	Partial correlation coefficient	95% CI	P value‡
Gestational age
<28 weeks	30	89.4±11.6	28	90.8±12.3	−1.4	−7.7 to 4.9	0.657	43	2.8±1.1	34	2.7±1.0	0.23	−0.585 to 1.046	0.580
≥28 weeks	24	92.1±13.6	37	91.3±15.9	0.9	−7.0 to 8.8	0.825	46	3.3±1.0	45	2.7±1.2	0.939	0.158 to 1.720	0.018
Birth weight
<1000 g	28	87.4±12.7	35	88.6±13.6	−1.1	−7.8 to 5.6	0.740	40	2.7±1.1	40	2.7±1.0	−0.006	−0.795 to 0.783	0.988
≥1000 g	26	94.0±11.5	30	9.40±14.9	0.1	−7.2 to 7.3	0.986	49	3.4±0.9	39	2.7±1.2	1.083	0.275 to 1.891	0.009
Light-for-dates
Yes	16	89.9±12.9	25	88.7±15.5	1.2	−8.2 to 10.6	0.796	30	3.0±1.1	28	2.6±1.1	0.696	−0.250 to 1.642	0.149
No	38	90.9±12.5	40	92.6±13.6	−1.6	−7.5 to 4.3	0.584	59	3.1±1.1	51	2.8±1.1	0.532	−0.154 to 1.218	0.129
Delivery
Caesarean	17	92.1±13.8	55	90.4±13.8	1.8	−5.9 to 9.4	0.648	37	3.2±1.1	68	2.6±1.1	1.093	0.324 to 1.861	0.005
Vaginal	37	89.9±12.0	10	94.9±17.3	−4.9	−14.4 to 4.6	0.301	52	2.9±1.0	11	3.1±0.9	−0.26	−1.454 to 0.934	0.669
Apgar score at 5 min
≥8	36	90.7±13.0	27	94.1±14.6	−3.4	−10.3 to 3.6	0.339	66	3.1±1.1	31	2.9±1.1	0.518	−0.268 to 1.305	0.197
<8	18	90.4±11.8	38	88.9±14.0	1.5	−6.2 to 9.1	0.698	22	2.7±1.0	48	2.6±1.1	0.191	−0.720 to 1.102	0.681
Antenatal steroid use
Yes	19	96.8±11.0	24	89.2±13.3	7.5	−0.1 to 15.2	0.054	31	3.2±1.0	31	2.7±1.1	1.108	0.161 to 2.055	0.022
No	35	87.3±12.1	41	92.1±15.0	−4.9	−11.2 to 1.4	0.129	58	2.9±1.1	48	2.8±1.1	0.331	−0.363 to 1.025	0.350
Sex
Male	31	88.6±13.3	38	92.6±14.5	−4.1	−10.8 to 2.7	0.234	52	2.9±1.1	44	2.8±1.1	0.159	−0.566 to 0.884	0.667
Female	23	93.4±11.0	27	88.9±14.1	4.5	−2.8 to 11.8	0.218	37	3.3±0.9	35	2.6±1.1	1.219	0.333 to 2.104	0.007
Total parenteral nutrition
Yes	53	90.2±12.2	62	90.6±14.3	−0.4	−5.4 to 4.5	0.862	75	2.9±1.0	70	2.7±1.0	0.376	−0.216 to 0.968	0.213
No	1	114	3	100.3±15.5	–	–	–	14	3.6±1.1	9	2.4±1.5	1.886	−0.070 to 3.842	0.059
Age at enteral feeding of 100 mL/kg/day
<13 days	30	92.0±11.5	37	95.3±13.5	−3.3	−9.5 to 2.9	0.287	49	3.1±1.0	44	3.0±1.1	0.267	−0.483 to 1.017	0.485
≥13 days	24	88.9±13.7	28	85.5±13.8	3.5	−4.2 to 11.2	0.369	40	2.9±1.1	35	2.4±1.1	0.996	0.154 to 1.837	0.020

*Developmental levels were determined in terms of the DQ18 scores, which were either computed or inferred (if developmental testing was unfeasible or unnecessary).
†Student’s t-test.
‡Ordered logistic regression analysis.
DQ18, developmental quotient at 18 months of corrected age.