In total, 2750 infants were excluded from all analyses because of absent data on all outcomes. There was little evidence that these infants with missing data were more likely to have needed resuscitation (8.0% vs 7.5%, p=0.33). shows the characteristics of the infants with any outcome measure recorded (n=8732), split by their birth condition. Data were incomplete for some covariates, and consequently the denominator for different measures varies. Mothers with infants who were resuscitated tended to have lower educational levels than those whose children did not received support at birth. First pregnancy, maternal hypertension, maternal fever during labour and caesarean section all occurred more frequently in infants requiring resuscitation. Birth weight was slightly lower, head circumference slightly higher and Apgar scores considerably lower in infants who were resuscitated and rates of CP differed by birth condition (p<0.001).
Characteristics of the study population by resuscitation and presence or absence of encephalopathy
Mean scores for reading accuracy (p=0.020) and comprehension (p=0.006) differed between the three categories of birth condition, while there was weaker evidence that working memory scores differed depending on the birth condition (p=0.065) (). shows the proportion of infants with a defined low score in each test. Risk of a low score in the comprehension test (p<0.001) and the provision of an educational statement (p=0.006) differed by birth condition, while there was weak evidence that the proportion of infants identified as having SEN depending on their birth condition (p=0.099).
Mean values in memory, attention and language test scores at ages 8–11 years for resuscitated and non-resuscitated infants
Proportion of children with low scores* for tests of memory, attention and language and with special educational needs at ages 8–11 years according to resuscitation status
In the final, adjusted linear regression model () there was little evidence for an association between any of the tests for memory, attention or language and the need for resuscitation among asymptomatic infants. Infants who developed encephalopathy following resuscitation had lower mean working memory (−6.65 (CI −12.34 to −0.96)), reading accuracy (−7.95 (CI −13.28 to −2.63)) and comprehension (−9.32 (CI −14.47 to −4.17)) scores.
Difference in mean memory, attention and language test scores at ages 8–11 years for resuscitated infants compared to those who were not resuscitated, split by birth condition
In the final logistic regression model () there was little evidence that resuscitated but asymptomatic infants had an increased risk of a low score in any measure, although adjusted ORs for six of the nine measures were indicative of worse outcomes in this group. Infants who developed encephalopathy following resuscitation had a higher risk of a low reading comprehension (OR 5.14 (2.06 to 12.80)), but limited evidence that they had higher risks of low scores in the other language, attention or memory tests, although the CI are wide and, for several measures, include the possibility of fourfold to fivefold increases in risk. Infants who developed encephalopathy also had substantially increased risk of having an educational statement (OR 6.24 (1.52 to 26.43)) or being reported to have SEN by their teacher (OR 3.10 (1.19 to 8.07)).
OR for low test score results* or the requirement for special educational needs for resuscitated infants compared to those not resuscitated, according to condition at birth
Repeating the analysis using infants with complete data only (‘complete case analysis’) produced stronger, but less precise, associations between resuscitation status and the need for an educational statement (asymptomatic infants, OR 1.69 (0.85 to 3.36), p=0.137; encephalopathic infants, OR 8.57 (1.58 to 46.66), p=0.013). Repeating the analysis with a fully imputed dataset produced slightly weaker associations between resuscitation status and the need for an educational statement (asymptomatic infants, OR 1.37 (0.76 to 2.45), p=0.290; encephalopathic infants, OR 7.17 (0.93 to 55.12), p=0.058). When the analysis was repeated excluding infants who developed CP the association between birth condition and an educational statement weakened considerably (asymptomatic, OR 1.24 (0.65 to 2.38), p=0.511; encephalopathic OR 2.14 (0.24 to 19.15), p=0.495).
There was little evidence that the association between resuscitation and receiving an educational statement differed by maternal education (pinteraction=0.787) or maternal socioeconomic group (pinteraction=0.240). However, there was evidence that the association between birth condition and receiving an educational statement differed by gender (pinteraction=0.007). When stratifying the results by gender, female infants had a higher risk of requiring a statement of educational need than males after poor condition at birth when compared to the reference group (asymptomatic infants: females OR 3.69 (1.60 to 8.51) vs males OR 0.71 (0.07 to 7.08), encephalopathic infants: females OR 9.36 (1.00 to 87.41) vs males OR 5.08 (0.28 to 93.42)), although CIs were wide. However, there was little evidence of a gender interaction with any other outcome.