Department of Economic and Social Affairs

Statistics • COVID-19 response
Ensuring continuity

Surviving the COVID stress test: the leading experience of KOSTAT

South Korea’s success in combating COVID-19 certainly has many lessons to offer to the rest of the world, so has its national statistical system. When the first shock of COVID-19 hit the country between early March to mid-April in 2020, Statistics Korea (KOSTAT) was at its busiest time preparing for a number of household surveys such as the household finances and living conditions survey and employment survey. Due to the complex questionnaire design, these surveys are usually carried out through face-to-face interviews. The COVID-19 lockdown hence became a serious stress test for KOSTAT and its household survey system.

KOSTAT is not alone in facing the COVID stress test. A survey conducted by the United Nations Statistical Division and the World Bank Development Data Group in May 2020 found that 96 percent of national statistical offices either partially or fully stopped face-to-face data collection at some point during the pandemic.

The statistical community has responded with leadership and inspiring stories of innovation. Many national statistical offices have adopted innovative approaches and/or turned to alternative data sources, with most countries adapting household surveys from face-to-face to other modes such as phone or web based surveys.

While COVID-19 will most likely be a catalyst for further innovation in household survey programmes, it is important for us to reflect on what has been done during this difficult period, what worked and what did not work so well, and how we can improve moving forward towards sustainable, timely and cost-effective data collection approaches. Documenting and sharing these reflections with others will contribute greatly to the entire statistical community.

This is why we reached out to Seoyoung Kim and her colleagues from Statistics Korea (KOSTAT) for an expanded paper on what steps it has taken in their household surveys during the pandemic. This follows an informative presentation she delivered during a webinar in February 2021, jointly organized by the Inter-Secretariat Working Group on Household Surveys (ISWGHS) and the Statistics Division of the Economic and Social Commission for Asia and the Pacific, on the impact of changing mode on official statistics.

The paper presents many important elements such as

  • contingency planning for the household survey programme at the start of the pandemic,
  • coordination between the central and regional statistical offices,
  • the use of administrative records to validate and correct household survey data,
  • assigning data collection mode to households and how the choice of the data collection mode varies by socioeconomic status of households,
  • methods used to assess the mode effect.

At the end of the paper the authors reflect on the lessons learned and provided a list of items that should be taken into consideration in the future. Notably, they conclude that mixed mode data collection can be a good strategy, but successful implementation brings various challenges beyond just developing the tools for remote data collection.

We congratulate KOSTAT for its immediate and statistically robust response to the challenge of COVID-19; and thank them for documenting and sharing their experiences. The authors are also grateful for input from Mr. Kieran Walsh, ILO Statistics Division; and for guidance from Francesca Perucci, United Nations Statistics Division.

Key words: COVID-19 impact, COVID-19 contingency plan, mode effect, mixed-mode, data integration



Seo-young Kim served as Director in Statistics Korea, and has been currently working as Technical Advisor of Popula-tion and Development Branch in UNFPA since August 2020. Seo-young has extensive experience in sta-tistical methodology and the data analysis, including the integration of survey and administrative data and studies on income inequality, wealth distribution and poverty indicators. Seo-young has also worked on small area estimation for many years, and she has been particularly participating UNFPA’s capacity strengthening in census analysis, demographic dividend, and small area estimation of SDGs, with a special focus on the fertility and well-being of older persons. Seo-young has a PhD in Statistics from Chonnam National University in South Korea.

Kyung Eun Lim is a Director of Welfare Statistics Division in Statistics Korea. For the past 7 years, she has led the Sampling Division. She worked on sampling design for Household Surveys. She is an expert in sampling design, survey method, and data analysis. She holds a Ph.D. degree in Statistics from the Sookmyung Women's University in South Korea.

Taejick Lee is a Deputy director of the Statistics Korea. He is in charge of planning household finances and living conditions survey. Before he joined the current position in August 2018, he has worked on various statistical areas including vital statistics, register-based population censuses and population projections. He holds a Master’s degree in Statistics from Chungnam National University in South Korea.

Haoyi Chen is the Coordinator of the Inter-Secretariat Working Group on Household Surveys. She works on methodologies related to household surveys with 11 international agencies and 8 countries. Before she joined the current position in September 2019, she led the programme on international migration statistics. She has also worked on various statistical areas including gender statistics, population censuses, civil registration and vital statistics. She holds a Ph.D degree in Statistics from the University of Florida.

Gemma Van Halderen is the Director of the Statistics Division of the UN Economic and Social Commission for Asia and the Pacific. She leads the Commission’s capacity building programmes for data and statistics. Before joining the UN, she was a member of the senior leadership team in the Australian Bureau of Statistics and has more than 30 years of experience in official statistical systems. She holds a Honours degree in Statistics from the Australian National University.