SRS vs. SMSS

Same Process, different names: Sample Registration System (SRS) and Sample-Based Mortality Surveillance System (SMSS)

Throughout the website, we refer to SRS as SMSS.

Setel and colleagues defined a SRS as “a community-based system implemented in a nationally representative cluster sample”¹. SRS is a sustained continuous rigorous data collection and analysis approach that relies on a sample of the population organized in geographic clusters and drawn to be nationally and sub-nationally representative with the aim of producing population empirical estimates of mortality and cause of death and other population demographics. The name SRS can be misleading as the system does not aim to legally register events births and identify deaths. Its main purpose is to generate data for statistics, as opposed to a CRVS which is mandated for legal registration and official documentation of vital events.

By design, an SRS does not exhaustively cover the entire population of a country but collects data from only a small fraction (1-5% depending on total population size) to make inferences on the entire population. Depending on resources and country needs, the population covered can be selected in such a way that population indicators measured are representative at specified statistical domains, which can be national, regional/provincial, or district-level. Thus, an SRS is a sample vital statistics system, often limited to most relevant vital events such as births, deaths, and population counts. Given the centrality of collecting mortality data, we will refer to it as a Sample-based Mortality Surveillance System (SMSS).

An SMSS involves:

• Continuous near real-time data collection on births, deaths, and causes of death, consistently with existing global or national standards.
• Ideally, updated population counts by age and sex.

• Geographically contained and sample-based estimates, whether national or subnational, with population representativeness

• Data analysis to produce reliable and interpretable estimates of
  all-causes and cause-specific mortality with relevant
  disaggregation (by age, sex, and other selected characteristics).

• Regular data release for use in policy and program
  decision-making, learning, and research.

Overview of How to Create an SMSS

Designing and successfully implementing an SMSS is a longterm commitment that must be guided by a government vision of establishing a sustainable surveillance system for rapid mortality and cause of death data generation and use. Such systems must be guided by six main principles that ensure that consideration and value is given to the existing data system through possible linkages or integration, key stakeholders and players at the country level are engaged, and progress and priority toward full functioning of civil registration and vital statistics is not diminished. The box below summarizes these six guiding principles. Countries or users may define additional principles depending on their specific context and objectives of the surveillance system being pursued.

Six Guiding Principles for Establishing a Mortality Surveillance
System

1. The collection of mortality statistics is complex and requires
   the involvment of multiple sectors and stakeholders that are
   interested in these statistics.

2. Many countries are already implementing various surveillance
   systems that are at different levels of maturity.

3. The proposed surveillance system must leverage and build on
   existing country digital tools and surveillance systems rather
   than creating a completely new and parallel system.

4. New platforms may be proposed to support additional data
   collection, in order to enhance or fill gaps in existing
   platforms, but they must incorporate linkages and
   interoperability with key existing government systems.

5. The proposed mortality surveillance system must value, support,
   and strengthen the country’s vision for establishing a long-term
   CVRS.

6. The proposed system has a data production function solely and
   does not seek to interfere with the legal framework of CRVS or
   the service delivery function of other existing systems, although
   it may support the optimal functionality of these systems
   regarding these objectives.

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1. Setel PW, Sankoh O, Rao C, Velkoff VA, Mathers C, Gonghuan Y et al. Sample registration of vital events with verbal autopsy: a renewed commitment to measuring and monitoring vital statistics. Bulletin of the World Health Organization 2005;83:611-617 ↩