Table 3.

Categories and criteria for Groups A, B and C in WHO preterm birth estimates

		WHO Member States
		Group A country	Group B country	Group C country
Quality Criteria	Source	Specific criteria
1. Preterm birth data available	Assess available CRVS data	CRVS data for preterm birth are available, ie: Preterm birth rate is given or can be calculated	CRVS data for preterm birth are available, ie: Preterm birth rate is given or can be calculated	No CRVS for preterm birth available, or CRVS data available but country does not otherwise meet Group A or B criteria
2. Quality of civil registration system for births	Civil registration coverage of births (%)	CRVS coverage for births >80 % [20] (or country can be otherwise classified as having high coverage for birth registration)	CRVS coverage for births is 60 % - <80 % [20]	CRVS coverage for birth data is <60 % or unknown [20]
3. Volume of CRVS data	Assess available CRVS data	• ≥500 births • Commencement date of data collection after 1/1/1990 • End date of data collection is before 31/12/2014 • Number of years where preterm data available is >50 % for the period 1990 to 2014 inclusive (i.e. CRVS data available for at least 13 years)	• ≥500 births • Commencement date of data collection after 1/1/1990 • End date of data collection is before 31/12/2014 • Data for any year/s between 1990 to 2014 inclusive (but does not meet Group A criteria)	• No CRVS data on preterm birth available, or • CRVS data on preterm birth available, but country does not otherwise meet Group A or Group B criteriaa
Data sources for development of estimates
Data sources:		CRVS data only to be used	Conduct systematic review of published studies to identify additional data sources	Conduct systematic review of published studies to identify additional data sources

^aCountries that have CRVS data for preterm birth, but CRVS coverage for birth data is <60 % or unknown, will be considered Group C countries