Making stillbirths count, making numbers talk - Issues in data collection for stillbirths

Table 1 Classification systems and their characteristics for use in low- and middle-income countries

Systems tested in low- or middle-income countries	Number of categories of stillbirths^a	Are intrapartum events captured in subcategories?	Does the system aim to capture underlying cause?	Are the main categories consistent with underlying cause?	Resources desirable for use^b	Does the system separate unknown from unexplained?	Agreement tested (Kappa score or level of agreement)	References
Aberdeen	8-0-0	no	yes	no	B	no	0.35-0.97	[49, 84, 93–95]
CODAC	10-94-577	yes	yes	yes	B, C	yes	0.65-0.94	[49, 50]
CODAC Simplified	10-30	yes	yes	yes	B, C	yes	no	[50]
ICD-10	17-134	yes	yes	yes/no	B	no	no	[23]
Nordic Baltic	13-0-0	no	no	no	A	no	0.85	[84]
Pattinson^c	12-48-0	yes	no	no	B	no	no	[96, 97]
PSANZ-PDC	11-52-33	yes/no	yes	yes/no	B, C	yes	0.63-0.90	[49, 86]
ReCoDe	9-28-1	yes/no	no	no	B, C	yes	0.51	[49, 98]
Tulip	6-24-7	no/yes	yes	yes	B, C	yes	0.74-0.86	[49, 87]
Whitfield^c	12-15-2	no	yes	no	B	no	no	[95, 99]
Wigglesworth	5-0-0	no	no	no	A	no	0.25-0.85	[49, 84]

^aNumber of main categories followed by subcategories.
^bA = little investigations and no placental examinations necessary; B = some clinical and pathological investigations necessary or desirable; C = placental investigations necessary or desirable (placental conditions included in the classification).
^cModified versions of the Aberdeen classification.
Acronyms: CODAC: Causes of Death and Associated Conditions, PSANZ-PDC: Perinatal Society of Australia and New Zealand Perinatal Death Classification, ReCoDe: Relevant Conditions of Death.