Sven Drefahl. Photo: Stockholm University

Sven Drefahl

Biträdande universitetslektor, Docent

View page in English
Arbetar vid Sociologiska institutionen
Telefon 08-16 22 87
Besöksadress Universitetsvägen 10 B, plan 9
Rum B 868
Postadress Sociologiska institutionen, Demografiska avdelningen 106 91 Stockholm

Om mig

I am Associate Professor (Docent) in Demography and I am currently studying the relationship between migration and mortality, determinants of COVID-19 mortality, and the ageing of the Swedish population. The majority of my research is based on individual-level register data of the total Swedish population. Beyond that I am also interested in international trends of health and mortality and demographic methods.

I am currently teaching demographic methods and statistical methods at the advanced level. Given that I am a Demographer using mainly longitudinal register data I have expert knowledge on most flavours of hazard regression (aka survival analysis, aka event-history analysis). I have also a longstanding interest in demographic microsimulations.

For my CV and more details please check also my (currently outdated) personal website(Click here)


I urval från Stockholms universitets publikationsdatabas
  • 2019. Andrea Monti (et al.). Population Studies

    Estimating the number of individuals living in a country is an essential task for demographers. This study assesses the potential bias in estimating the size of different migrant populations due to over-coverage in population registers. Over-coverage-individuals registered but not living in a country-is an increasingly pressing phenomenon; however, there is no common understanding of how to deal with over-coverage in demographic research. This study examines different approaches to and improvements in over-coverage estimation using Swedish total population register data. We assess over-coverage levels across migrant groups, test how estimates of age-specific death and fertility rates are affected when adjusting for over-coverage, and examine whether over-coverage can explain part of the healthy migrant paradox. Our results confirm the existence of over-coverage and we find substantial changes in mortality and fertility rates, when adjusted, for people of migrating age. Accounting for over-coverage is particularly important for correctly estimating migrant fertility.

  • 2017. Gunnar Andersson, Sven Drefahl. Population, Space and Place 23 (4)

    International migrants often have lower mortality rates than the native populations in their new host countries. Several explanations have been proposed, but in the absence of data covering the entire life courses of migrants both before and after each migration event, it is difficult to assess the validity of different explanations. In the present study, we apply hazard regressions to Swedish register data to study the mortality of long-distance migrants from Northern to Southern Sweden as well as the mortality of return migrants to the North. In this way, we can study a situation that at least partly resembles that of international migration while still having access to data covering the full demographic biographies of all migrants. This allows us to test the relative roles of salmon bias and healthy migrant status in observed mortality rates of long-distance migrants. We find no mortality differentials between residents in northern and southern Sweden, and no evidence of a selection of healthy migrants from the North to the South. In contrast, we provide clear evidence of salmon effects' in terms of elevated mortality of the return migrants to northern Sweden, which are produced when migrants return to their place of origin in relation to subsequent death.

  • 2014. Sven Drefahl, Anders Ahlbom, Karin Modig. PLoS ONE 9 (2), e88357

    Background: In the beginning of the 1970s, Sweden was the country where both women and men enjoyed the world's longest life expectancy. While life expectancy continues to be high and increasing, Sweden has been losing ground in relation to other leading countries. Methods: We look at life expectancy over the years 1970-2008 for men and women. To assess the relative contributions of age, causes of death, and smoking we decompose differences in life expectancy between Sweden and two leading countries, Japan and France. This study is the first to use this decomposition method to observe how smoking related deaths contribute to life expectancy differences between countries. Results: Sweden has maintained very low mortality at young and working ages for both men and women compared to France and Japan. However, mortality at ages above 65 has become considerably higher in Sweden than in the other leading countries because the decrease has been faster in those countries. Different trends for circulatory diseases were the largest contributor to this development in both sexes but for women also cancer played a role. Mortality from neoplasms has been considerably low for Swedish men. Smoking attributable mortality plays a modest role for women, whereas it is substantially lower in Swedish men than in French and Japanese men. Conclusions: Sweden is losing ground in relation to other leading countries with respect to life expectancy because mortality at high ages improves more slowly than in the leading countries, especially due to trends in cardiovascular disease mortality. Trends in smoking rates may provide a partial explanation for the trends in women; however, it is not possible to isolate one single explanatory factor for why Sweden is losing ground.

  • 2012. Sven Drefahl. Journal of Marriage and Family 74 (3), 462-475

    Numerous studies have shown that married women and men experience the lowest mortality. Legal marital status, however, does not necessarily reflect today's social reality because individuals are classified as never married, widowed, or divorced even when they are living with a partner. Denmark is one of the forerunners of developments in coresidential partnerships and one of only a few countries where administrative sources provide individual-level information on cohabitation for the whole population. Using register information from Statistics Denmark on 3,888,072 men and women ages 18–65, the author investigated mortality differences by living arrangement with hazard regression models. Overall, premature mortality was found to be lowest for married persons, followed by cohabiting persons. Adjusting for socioeconomic status reduced excess mortality of nonmarried individuals. Moreover, a mortality-crossover effect emerged in which cohabiters with above-average socioeconomic status had a lower risk of dying than married people. This finding was particularly pronounced for men.

  • 2010. Sven Drefahl. Demography 47 (2), 313-326

    I use hazard regression methods to examine how the age difference between spouses affects their survival. In many countries, the age difference between spouses at marriage has remained relatively stable for several decades. In Denmark, men are, on average, about three years older than the women they marry. Previous studies of the age gap between spouses with respect to mortality found that having a younger spouse is beneficial, while having an older spouse is detrimental for one's own survival. Most of the observed effects could not be explained satisfactorily until now, mainly because of methodological drawbacks and insufficiency of the data. The most common explanations refer to selection effects, caregiving in later life, and some positive psychological and sociological effects of having a younger spouse. The present study extends earlier work by using longitudinal Danish register data that include the entire history of key demographic events of the whole population from 1990 onward. Controlling for confounding factors such as education and wealth, results suggest that having a younger spouse is beneficial for men but detrimental for women, while having an older spouse is detrimental for both sexes.

Visa alla publikationer av Sven Drefahl vid Stockholms universitet

Senast uppdaterad: 17 oktober 2020

Bokmärk och dela Tipsa