Background
Methods
Record linkage
Statistics
Test(s) | Subjects tested | All tests positive | At least one test positive | ||
---|---|---|---|---|---|
Number of subjects | % | Number of subjects | % | ||
All three tests
| 26 | 1 | 4 | 12 | 46 |
Two tests
| |||||
Fetal scalp and umbilical arterial blood pH | 178 | 27 | 15 | 77 | 43 |
Umbilical arterial and venous pH | 41,245 | 3,583 | 9 | 8,866 | 21 |
Fetal scalp and umbilical venous blood pH | 4 | 0 | 0 | 0 | 0 |
One test
| |||||
Fetal scalp pH | 47 | 16 | 34 | 16 | 34 |
Umbilical arterial blood pH | 75,775 | 7,727 | 10 | 7,727 | 10 |
Venous umbilical blood pH | 3,561 | 385 | 11 | 385 | 11 |
Any of the three tests
| 120,836 | 11,739 | 10 | 17,083 | 14 |
Results
Child's Gender | Autism Spectrum Disorders | Fetal Hypoxia | Total | ||
---|---|---|---|---|---|
Present2
| Absent4
| Unknown | |||
Both | Present N | 113 | 530 | 495 | 1,138 |
%
3
|
0.66
|
0.60
|
0.44
|
0.52
| |
(0.06) | (0.03) | (0.02) | (0.02) | ||
Total N | 17,083 | 88,553 | 113,254 | 218,890 | |
Male | Present N | 100 | 452 | 400 | 952 |
%
3
|
1.10
|
0.99
|
0.70
|
0.85
| |
(0.11) | (0.05) | (0.03) | (0.03) | ||
Total N | 9,109 | 45,594 | 57,257 | 111,960 | |
Female | Present N | 13 | 78 | 95 | 186 |
%
3
|
0.16
|
0.18
|
0.17
|
0.17
| |
(0.04) | (0.02) | (0.02) | (0.01) | ||
Total N | 7,974 | 42,959 | 55,997 | 106,930 |
All gestational ages at birth | ||||||
---|---|---|---|---|---|---|
Unadjusted | Adjusted | |||||
Child's Gender | Both | Male | Female | Both3
| Male4
| Female4
|
Odds ratio estimate
| 1.15 | 1.14 | 0.93 | 1.11 | 1.13 | 0.94 |
95% confidence interval
| 0.98, 1.33 | 0.97, 1.34 | 0.62, 1.40 | 0.95, 1.29 | 0.96, 1.33 | 0.62, 1.41 |
P-value
| 0.08 | 0.11 | 0.74 | 0.19 | 0.14 | 0.76 |
Full-term births only
| ||||||
Unadjusted
|
Adjusted
| |||||
Child's Gender | Both | Male | Female | Both3
| Male4
| Female4
|
Odds ratio estimate
| 1.11 | 1.10 | 0.92 | 1.07 | 1.09 | 0.93 |
95% confidence interval
| 0.94, 1.31 | 0.93, 1.31 | 0.60, 1.42 | 0.91, 1.34 | 0.91, 1.29 | 0.60, 1.56 |
P-value
| 0.21 | 0.23 | 0.71 | 0.42 | 0.35 | 0.74 |
Deviation from MAR3
| Strong | Strong | Moderate | Weak |
---|---|---|---|---|
r
|
0.1
|
0.2
|
0.5
|
0.7
|
Odds ratio estimate
| 1.28 | 1.28 | 1.24 | 1.20 |
95% confidence interval
| 1.03, 1.60 | 1.03, 1.58 | 1.01, 1.52 | 0.99, 1.46 |
P-value
| 0.03 | 0.03 | 0.04 | 0.06 |