Contact: email

Current position: Visiting Research Fellow at Duke University Population Research Institute and Duke Global Health Institute

Experience: Ten years of quantitative research experience using econometrics, demographic methods, and GIS on pooled surveys and demographic data. Over 30 peer-reviewed articles in medical, public health, and demography journals since 2019.

Skills: Expert user of Stata. Experienced user of JavaScript (D3), Python, R, and Excel. Excellent written and verbal communication skills. I emphasize readability and accessibility to make my research assessable and applicable across disciplines and by decision-makers. I have participated in many successful interdisciplinary collaborations, locally and abroad.

Research interests: I study life expectancy, child health, living standards, and social determinants. Life-course perspectives and the human development framework motivate my research: wellbeing is improved by enhancing capabilities of individuals which are in turn strengthened through promoting opportunities and limiting adversity. This view is inspired by the work of Isaiah Berlin, James Heckman, and Amartya Sen.

Further information: CV (pdf)

Journal articles

• Age Decomposition of Mortality Rates Among Children Younger Than 5 Years in 47 LMICs.
  By Karlsson O, Pullum TW, Kumar A, Kim R, Subramanian SV
  in JAMA Pediatrics, 2025.
• Global health 2050: the road to halving premature death by mid-century.
  By Jamison DT, Summers LH, Chang AY, Karlsson O, Mao W, Norheim OF, Ogbuoji O, Schäferhoff M, Watkins D, Adeyi O, Alleyne G, Alwan A, Anand S, Nigatu Belachew R, Berkley S, Bertozzi S, Bolongaita S, Bundy D, …, & Yamey G
  in The Lancet, 2024.
• Halving premature death and improving the quality of life at all ages.
  By Norheim OF, Chang AY, Bolongaita S, Barraza-Lloréns L, Fawole A, Gebremedhin LD, González Pier E, Jha P, Johnson E, Karlsson O, Kiros, M, Lewington S, Mao W, Ogbuoji O, Pate M, Sargent J, Tang X, Watkins D, Yamey G, Yip W, Jamison D & Peto R
  in The Lancet, 2024.
• International Trends in Zinc Treatment for Diarrhea.
  By Karlsson O, Kim R & Subramanian SV
  in Pediatrics, 2024.
• Prevalence and Trends of Not Receiving a Dose of DPT-Containing Vaccine Among Children 12-35 Months: An Analysis of 81 Low- And Middle-Income Countries.
  By Karlsson O, Rajpal S, Johri M, Kim R & Subramanian SV
  in Journal of Epidemiology and Global Health, 2024.
• Association between neonatal mortality and births not weighed among 400 thousand institutional deliveries in 32 low- and middle-income countries.
  By Karlsson O, Benski C, Kapoor M, Kim R & Subramanian SV
  in Journal of Public Health, 2024.
• Relationship between adolescent anemia and school attendance observed during a nationally representative survey in India.
  By De Neve JW, Karlsson O, Rai RK, Kumar S & Vollmer S
  in Communications Medicine, 2024.
• Prevalence of Children Aged 6 to 23 Months Who Did Not Consume Animal Milk, Formula, or Solid or Semisolid Food During the Last 24 Hours Across Low- and Middle-Income Countries.
  By Karlsson O, Kim R & Subramanian SV
  in JAMA Network Open, 2024.
• Washing machine ownership and girls' school attendance: a cross-sectional analysis of adolescents in 19 middle-income countries.
  By Karlsson O & De Neve JW
  in Journal of Economic Inequality, 2024.
• Refrigerator ownership and child health and nutrition in low- and middle-income countries.
  By Karlsson O & Subramanian SV
  in Global Food Security, 2023.
• Patterns in child stunting by age: A cross-sectional study of 94 low- and middle-income countries.
  By Karlsson O, Kim R, Moloney GM, Hasman A & Subramanian SV
  in Maternal and Child Nutrition, 2023.
• Maternal height and child health and schooling in sub-Saharan Africa: Decomposition and heterogeneity.
  By Karlsson O & Dribe M
  in Social Science & Medicine, 2022.
• Childhood Diarrhea Prevalence and Uptake of Oral Rehydration Solution and Zinc Treatment in Nigeria.
  By Egbewale BE, Karlsson O & Sudfeld CR
  in Children, 2022.
• Age Distribution of All-Cause Mortality Among Children Younger Than 5 Years in Low- and Middle-Income Countries.
  By Karlsson O, Kim R, Hasman A & Subramanian SV
  in JAMA Network Open, 2022.
• Inequality in early life: Social class differences in childhood mortality in southern Sweden, 1815–1967.
  By Dribe M & Karlsson O
  in Economic History Review, 2022.
• Child wasting before and after age two years: A cross-sectional study of 94 countries.
  By Karlsson O, Kim R, Guerrero S, Hasman A & Subramanian SV
  in EClinicalMedicine, 2022.
• Estimating heritability of height without zygosity information for twins under five years in low- and middle-income countries: An application of normal finite mixture distribution models.
  By Karlsson O, Domingue BW, Kim R & Subramanian SV
  in SSM - Population Health, 2022.
• Maternal height-standardized prevalence of stunting in 67 low- and- middle-income countries.
  By Karlsson O, Kim R, Bogin B & Subramanian SV
  in Journal of Epidemiology, 2022.
• Scarring and selection effects on children surviving elevated rates of postneonatal mortality in sub-Saharan Africa.
  By Karlsson O
  in SSM - Population Health, 2022.
• Consumption of Vitamin-A-Rich Foods and Vitamin A Supplementation for Children under Two Years Old in 51 Low- and Middle-Income Countries.
  By Karlsson O, Kim R, Hasman A & Subramanian SV
  in Nutrients, 2021.
• Trends in underweight, stunting, and wasting prevalence and inequality among children under three in Indian states, 1993-2016.
  By Karlsson O, Kim R, Sarwal R, James KS & Subramanian SV
  in Scientific Reports, 2021.
• Distribution of under-5 deaths in the neonatal, postneonatal, and childhood periods: a multicountry analysis in 64 low- and middle-income countries.
  By Li, Z, Karlsson O, Kim R & Subramanian SV
  in International Journal for Equity in Health, 2021.
• Children's education and parental old-age health: Evidence from a population-based, nationally representative study in India.
  By Thoma B, Sudharsanan N, Karlsson O, Joe W, Subramanian SV & De Neve JW
  in Population Studies, 2021.
• Changing speed of reduction in under-5 mortality rates over the 20th century.
  By Karlsson O, Dribe M & Subramanian SV
  in Journal of Epidemiology and Community Health, 2020.
• Analysis of Attained Height and Diabetes Among 554,122 Adults Across 25 Low- and Middle-Income Countries.
  By Teufel F, Geldsetzer P, Manne-Goehler J, Karlsson O, Koncz V, Deckert A, Theilmann M, Marcus M-E, Ebert C, Seiglie JA, Agoudavi K, Andall-Brereton G, Gathecha G, Gurung MS, Guwatudde D, Houehanou C, Hwalla N, Kagaruki GB, Karki KB, Labadarios D, Martins JS, Msaidie M, Norov B, Sibai AM, Sturua L, Tsabedze L, Wesseh CS, Davies J, Atun R, Vollmer S, Subramanian SV, Bärnighausen T, Jaacks LM & De Neve JW
  in Diabetes Care, 2020.
• Geo-mapping of COVID-19 Risk Correlates Across Districts and Parliamentary Constituencies in India.
  By Subramanian SV, Karlsson O, Zhang W & Kim R
  in Harvard Data Science Review, 2020.
• The effects of economic stress and urbanization on driving behaviours of boda-boda drivers and accidents in gulu, northern uganda: A qualitative view of drivers.
  By Kitara DL & Karlsson O
  in Pan African Medical Journal, 2020.
• Are out-of-school adolescents at higher risk of adverse health outcomes? Evidence from 9 diverse settings in sub-Saharan Africa.
  By De Neve JW, Karlsson O, Canavan CR, Chukwu A, Adu-Afarwuah S, Bukenya J, Darling AM, Harling G, Moshabela M, Killewo J, Fink G, Fawzi WW & Berhane Y
  in Tropical Medicine & International Health, 2020.
• The relationship of household assets and amenities with child health outcomes: an exploratory cross-sectional study in India 2015–2016.
  By Karlsson O, Kim R, Joe W & Subramanian SV
  in SSM - Population Health, vol. 10, 100513.
• Religion and child health in West and Central Africa.
  By Karlsson O
  in Population and Development Review, 2019.
• Socioeconomic and gender inequalities in neonatal, postneonatal and child mortality in India: A repeated cross-sectional study, 2005-2016.
  By Karlsson O, Kim R, Joe, W & Subramanian SV
  in Journal of Epidemiology and Community Health, 2019.
• Antiretroviral therapy coverage associated with increased co-residence between older and working-age adults in Africa.
  By De Neve JW, Karlsson O, Coetzee L, Schröder H, Subramanian SV, Bärnighausen T & Vollmer S
  in AIDS, 2018.
• Weakening association of parental education: analysis of child health outcomes in 43 low- and middle-income countries.
  By Karlsson O, De Neve JW & Subramanian SV
  in International Journal of Epidemiology, 2018.

Journal correspondence and comments

• Should India adopt a country-specific growth reference to measure undernutrition among its children? [Comment]
  By Subramanian SV, Khailkar A & Karlsson O
  in The Lancet Regional Health - Southeast Asia, 2023.
• Using height-adjusted stunting prevalence will fail disadvantaged children worldwide, authors reply. [Correspondence]
  By Subramanian SV, Karlsson O & Kim R
  in The Lancet Global Health, 2022.
• Revisiting the stunting metric for monitoring and evaluating nutrition policies. [Comment]
  By Subramanian SV, Karlsson O & Kim R
  in The Lancet Global Health, 2022.
• Lessons from COVID-19 pandemic for the child survival agenda.[Comment]
  By Subramanian SV, Chatterjee P & Karlsson O
  in Journal of Global Health, 2020.

Data Dashboard for the Lancet Commission on Investing in Health

I created (using JavaScript D3) and host an interactive dashboard displaying visualizations of key metrics, trends, and projections for the Lancet Commission on Investing in Health. This allows commissioners to explore data layers and generate displays as needed.

Global health 2050: the path to halving premature death by mid-century

The third report of the Lancet Commission on Investing in Health (CIH) emphasizes that by 2050, all countries can halve the probability of premature death—defined as dying before the age 70 years—through targeted investments in health systems and interventions. This goal, referred to as "50 by 50," is both ambitious and achievable, demonstrated by impressive mortality declines in countries as diverse as Bangladesh, Ethiopia, Iran, Türkiye, Norway, and South Korea.

The report identifies 15 priority health conditions: eight infectious diseases and maternal and child conditions and seven non-communicable diseases and injuries, such as cardiovascular disease, diabetes, and tobacco-related cancers. In the countries with the highest mortality rates, infectious diseases and maternal and child health need to be addressed. All countries need to combat non-communicable diseases and injuries.

The report stresses the importance of strengthening health systems, particularly primary care and first-level hospitals, to manage the 15 priority conditions, by packaging health interventions into 19 modules, such as childhood immunization and cardiovascular disease prevention and treatment, which will help countries tailor their health investments to their specific needs.

Achieving the 50 by 50 goal also requires systemic changes in how countries allocate their health budgets. Many countries fail to direct sufficient resources toward priority interventions. Governments need to redirect budgets toward essential drugs, vaccines, diagnostics, and other commodities needed to reduce mortality from the 15 priority conditions. Procurement systems should be centralized and scaled to ensure that these health products are always available. Tobacco control is highlighted as a critical area, with the report recommending high excise taxes on tobacco and other policies to curb tobacco-related deaths and (initially) raise important revenue.

In addition to national reforms, the report calls for renewed commitments from the international development community. Development assistance should primarily provide financial and technical support to countries with limited resources, to help develop their health systems. It should also finance global public goods, such as combating antimicrobial resistance and preparing for future pandemics. The report stresses that significant advances in health technology—such as vaccines for malaria and tuberculosis—are on the horizon, and scaling up investments in these and other innovations will be crucial to achieving the 50 by 50 goal.

Lancet Commission on Investing in Health website

CIH articles I co-authored

• Jamison DT, Summers LH, Chang AY, Karlsson O, Mao W, Norheim OF, Ogbuoji O, Schäferhoff M, Watkins D, Adeyi O, Alleyne G, Alwan A, Anand S, Nigatu Belachew R, Berkley S, Bertozzi S, Bolongaita S, Bundy D, … & Yamey G (2024). Global health 2050: the road to halving premature death by mid-century. The Lancet, 404(10462), 1561-1614.
• Norheim OF, Chang AY, Bolongaita S, Barraza-Lloréns L, Fawole A, Gebremedhin LD, González Pier E, Jha P, Johnson E, Karlsson O, Kiros, M, Lewington S, Mao W, Ogbuoji O, Pate M, Sargent J, Tang X, Watkins D, Yamey G, Yip W, Jamison D & Peto R (2024). Halving premature death and improving the quality of life at all ages. The Lancet.

CIH working papers I led

• Karlsson O, Jamison D, Yamey G, Bolongaita S, Mao W, Chang AY, Norheim OF, Ogbuoji O & Verguet S (2024). Probability of death before age 70: progress as years behind or ahead of the global average trend. CIH background paper.
• Karlsson O, Chang AY, Norheim OF, Mao W, Bolongaita S & Jamison D (2024). Priority health conditions and life expectancy deficits by cause of death. CIH background paper.

CIH working papers I co-authored

• Chang AY, Karlsson O & Jamison D (2024). Quantifying the economic value of mortality change and full income change for 1990-2019 and the COVID-19 pandemic 2020-2023. CIH background paper.
• Chang AY, Bolongaita S, Karlsson O, Mao W, Norheim OF & Jamison D (2024). Epidemiological and demographic trends in global health 1970-2050: Analysis from the Lancet Commission on Investing in Health. CIH background paper.
• Chang AY, Johnson EK, Bolongaita S, Buse K, Hawkes SJ, Karlsson O, Knaul FM, Kruk M, Norheim OF, Ogbuoji O & Wakings D (2024). Balancing the scales: Towards a more objective measure of sex inequalities in health. CIH background paper.

Improving nutrition and survival for the youngest and most vulnerable children

For this project, I led four scientific studies on the age distribution of important child health outcomes. These studies resulted in four journal publications and a workshop with UNICEF staff.

The first two years after birth are a critical period for growth and development, when malnutrition and infections have the most detrimental impact on child health, as well as human development more broadly. During the first two years, children's bodies and brains are developing rapidly, and they are more susceptible to stunting (low height-for-age) and wasting (low weight-for-height), which significantly increases their risk of death. Malnutrition during this period weakens the immune system, making children more prone to infections, which in turn can exacerbate undernutrition.

The project demonstrated that most child deaths and malnutrition cases are concentrated in children under two years of age. This suggests that prioritizing nutrition programs for this age group could have the greatest impact on reducing child mortality and improving health outcomes. However, the coverage of essential nutrition interventions remains far from complete and highly inequitable, with children from poorer households or rural areas often deprived of the nutrition and care they need. This calls for better strategies to reach the most vulnerable children through well-resourced nutrition programs.

Journal articles from the project

• Karlsson O, Kim R, Moloney GM, Hasman A & Subramanian SV (2023). Patterns in child stunting by age: A cross-sectional study of 94 low- and middle-income countries. Maternal and Child Nutrition, 19(4).
• Karlsson O, Kim R, Hasman A & Subramanian SV (2022). Age Distribution of All-Cause Mortality Among Children Younger Than 5 Years in Low- and Middle-Income Countries. JAMA Network Open, 5(5), e2212692.
• Karlsson O, Kim R, Guerrero S, Hasman A & Subramanian SV (2022). Child wasting before and after age two years: A cross-sectional study of 94 countries. EClinicalMedicine, 46, 101353.
• Karlsson O, Kim R, Hasman A & Subramanian SV (2021). Consumption of Vitamin-A-Rich Foods and Vitamin A Supplementation for Children under Two Years Old in 51 Low- and Middle-Income Countries. Nutrients, 14(1).

Various measures of socioeconomic status exist, such as education, occupation, and income, which reflect different underlying attributes that vary in the ways and degree to which they translate into health. In low- and middle-income countries that lack reliable income data, socioeconomic status is commonly measured by wealth indices, constructed from data on ownership of assets (refrigerator, TV, car, etc) and amenities (electricity, toilet, water, etc). Many of these assets and amenities appear to merely reflect aspects of socioeconomic status (or living standards) without direct links to child health. However, my colleagues and I identified assets related to food preparation and storage as well as water and sanitation, as potential direct determinants of child health.

To further establish linkages, I started a project funded by the Swedish Research Council, to study whether and when household technology can improve nutrition, reduce infections, and reduce child labor, thereby improving child health and education in low- and middle-income countries. For example, refrigerators may improve nutrition by increasing the consumption of protein-rich perishable foods and reduce sickness due to food contamination from improper food storage. Electricity, appliances, and piped water can also reduce the burden from household work, allowing parents to augment incomes from other work, improve the quality of household work (eg, hygiene), and increase direct supervision of children, as well as reducing the need for child labor, enabling children—especially girls—to attend school.

This project advanced understanding of whether household technology can improve child health and education in low- and middle-income countries. A large increase in electricity access and appliance ownership was found. At the population level, both increases in electricity access and refrigerator ownership were suggested to be linked to improved child health and nutrition. Further, by analyzing an extensive data set from 66 countries, one study established that children in households with refrigerators exhibited notable improvements in physical growth, a key indicator of nutrition and infections. Although the effect size was modest, it is significant enough to suggest that refrigerator ownership can play a role in reducing undernutrition and infections by enabling increased consumption and safer storage of perishable foods. Further, another study from the project found tentative evidence that household electricity access positively affects child growth, which appears to be mediated by appliance ownership to an extent.

Another paper resulting from this project unveiled a strong association between washing machine ownership and school attendance among girls and not boys, but only in specific contexts. This underscores the importance of contextual factors in assessing the impact of household technology on educational outcomes. Similarly, another study found that time spent on household work is negatively associated with girls' school attendance in most countries, which further explained a substantial part of the female disadvantage in school attendance. However, the relationship of appliance ownership with household work and school attendance was overall unclear and highly context dependent.

Evidence from this project highlight the potential of refrigerators to improve child nutrition and reduce exposure to infections, as well as time-saving appliances to improve girls' school attendance. These findings can be leveraged to advocate for the financing of trials on the effects of appliance ownership on child health and schooling (eg, through provision or subsidization) across low- and middle-income countries, for gathering further evidence.

Journal articles from the project

• Karlsson O & De Neve JW (2024). Washing machine ownership and girls' school attendance: a cross-sectional analysis of adolescents in 19 middle-income countries. Journal of Economic Inequality.
• Karlsson O & Subramanian SV (2023). Refrigerator ownership and child health and nutrition in low- and middle-income countries. Global Food Security, 37, 100698.

Pilot study for the project

• Karlsson O, Kim R, Joe W & Subramanian SV (2020). The relationship of household assets and amenities with child health outcomes: an exploratory cross-sectional study in India 2015–2016. SSM - Population Health, 10, 100513.

Presentations and draft papers

• Karlsson O (2022). Ownership of appliances, household work, and girls' school attendance and performance. Unpublished manuscript
• Karlsson O (2020). Household technology and human development in low and middle income countries. Presentation for Harvard Center for Population and Development
• Karlsson O (2020). Access to electricity and child health in 22 low and middle-income countries. Presentation for The Takemi Fellowship in international Health

In this project I led several studies on height (and co-authored others), investigating what underlies this common measure of health. For example, physical growth, a common measure of child health and development, reflects different processes (eg, diet, infections, and parental height) that may vary in the extent to which they reflect health. My colleagues and I find that at the population level, the prevalence of child growth deficit signals health considerably better after factoring out the influence of maternal height (which is determined by her childhood exposures and genetics and is the strongest observable determinant of child growth). Further, maternal height appears to be linked directly with neonatal mortality while the link between maternal height and mortality later in childhood appears to be related to material living standards and unobserved father characteristics, suggesting that pregnancy and birth related factors are important underlying mechanisms.

Journal articles I led

• Karlsson O & Dribe M (2022). Maternal height and child health and schooling in sub-Saharan Africa: Decomposition and heterogeneity. Social Science & Medicine, 315, 115480.
• Karlsson O (2022). Scarring and selection effects on children surviving elevated rates of postneonatal mortality in sub-Saharan Africa. SSM - Population Health, 19, 101160.
• Karlsson O, Kim R, Bogin B & Subramanian SV (2022). Maternal height-standardized prevalence of stunting in 67 low- and- middle-income countries. Journal of Epidemiology, 32(7), pp. 337.
• Karlsson, O, Domingue BW, Kim R & Subramanian SV (2022). Estimating heritability of height without zygosity information for twins under five years in low- and middle-income countries: An application of normal finite mixture distribution models. SSM - Population Health, 17, 101043.
• Karlsson O, Kim R, Sarwal R, James KS & Subramanian SV (2021). Trends in underweight, stunting, and wasting prevalence and inequality among children under three in Indian states, 1993-2016. Scientific Reports, 11, 14137.

Related journal articles I co-authored

• Teufel F, Geldsetzer P, Manne-Goehler J, Karlsson O, Koncz V, Deckert A, Theilmann M, Marcus ME, Ebert C, Seiglie JA, Agoudavi K, Andall-Brereton G, Gathecha G, Gurung MS, Guwatudde D, Houehanou C, Hwalla N, Kagaruki GB, Karki KB, Labadarios D, Martins JS, Msaidie M, Norov B, Sibai AM, Sturua L, Tsabedze L, Wesseh CS, Davies J, Atun R, Vollmer S, Subramanian SV, Bärnighausen T, Jaacks LM & De Neve JW (2020). Analysis of Attained Height and Diabetes Among 554,122 Adults Across 25 Low- and Middle-Income Countries. Diabetes Care, 43(10), pp. 2403-2410.

Journal correspondence and comments I co-authored

• Subramanian SV, Khailkar A & Karlsson O (2023). Should India adopt a country-specific growth reference to measure undernutrition among its children? The Lancet Regional Health - Southeast Asia, 9. [Comment]
• Subramanian SV, Karlsson O & Kim R (2022). Using height-adjusted stunting prevalence will fail disadvantaged children worldwide, authors reply. The Lancet Global Health, 10(5), e621. [Correspondence]
• Subramanian SV, Karlsson O & Kim R (2022). Revisiting the stunting metric for monitoring and evaluating nutrition policies. The Lancet Global Health, 10(2), e179-e180. [Comment]