Table 2.

Clinician validation of start and end dates of both inferred and recorded pregnancy episodes

		Algorithmic concordance (% episodes) with clinician-assigned date ± buffer			Clinicians’ average confidence score (−1, 0, 1)	Standard deviation of clinicians’ confidence scores
		±7 days	±14 days	±21 days
Inferred start date of inferred pregnancy episodea
Outcome	Live birth	93.8	98.8	100.0	0.56	0.52
	Stillbirth	86.8	92.1	94.7	0.42	0.60
	Abortion	85.2	92.6	96.3	0.04	0.84
	Ectopic pregnancy	87.5	91.7	91.7	−0.04	0.89
No outcome		96.4	96.4	96.4	0.61	0.57
Inferred end date of inferred pregnancy episode (outcome only)
Outcome	Live birth	97.5	98.8	100.0	0.80	0.40
	Stillbirth	100.0	100.0	100.0	0.61	0.55
	Abortion	91.9	94.6	94.6	0.42	0.50
	Ectopic pregnancy	90.9	90.9	90.9	0.48	0.62
Start date of recorded pregnancy episode
Outcome	Live birth	68.8	71.3	77.5	0.84	0.40
	Stillbirth	68.4	78.9	84.2	0.79	0.41
	Abortion	73.0	78.4	81.1	0.78	0.48
	Ectopic pregnancy	97.0	100.0	100.0	0.88	0.33
No outcome		65.5	69.0	72.4	0.83	0.385
End date of recorded pregnancy episode
Outcome	Live birth	91.3	93.8	97.5	0.79	0.41
	Stillbirth	84.2	86.8	89.5	0.68	0.57
	Abortion	94.6	97.3	97.3	0.54	0.56
	Ectopic pregnancy	78.8	81.8	93.9	0.52	0.62
No outcome		75.9	82.8	82.8	0.72	0.45

As these cases were randomly selected for clinician validation, they do not reveal information about the subpopulation and are not subject to the same policy regarding masking small numbers of patients.

^aNot all episodes have ascertainable start dates.