Substudy 1: Educational differences in disability-free life
Transcription
Substudy 1: Educational differences in disability-free life
Substudy 1: Educational differences in disability-free life expectancy: a comparative study of long-standing activity limitation in eight European countries Netta Mäki1*, Pekka Martikainen1, Terje Eikemo2, Gwen Menvielle3, Olle Lundberg4 5, Olof Östergren4, Domantas Jasilionis6, Johan Mackenbach2 & the EURO-GBD-SE consortium† 1 Department of Social Research University of Helsinki Finland 2 Department of Public Health Erasmus MC University Medical Center Rotterdam Netherlands 3 l'Institut national de la santé et de la recherche médicale France 4 CHESS | Centre for Health Equity Studies Sweden 5 Department of Health Sciences, Mid Sweden University Sweden 6 Max Planck Institute for Demographic Research Germany *Corresponding author: Department of Social Research, P.O.Box 18, FIN-00014 University of Helsinki, Finland E-mail: [email protected] † Carme Borrell, Maica Rodríguez-Sanz, Enrique Regidor 6 ABSTRACT Background Research comparing socioeconomic differences in health between countries has mostly been limited to various measures of either morbidity or mortality. This study combines these data to yield a summary measure of population health for a broad age-group. Educational differences in disability-free life expectancy are studied for eight countries from all parts of Europe in the early 2000s. Methods Long-standing severe disability was measured as a Global Activity Limitation Indicator (GALI) derived from the European Union Statistics on Income and Living Conditions (EUSILC) survey. Census-linked mortality data were collected by the EURO-GBD-SE project. We calculated sex-specific educational differences in partial disability-free life expectancy between the ages 30 and 79 years using the Sullivan method. Results Disability-free life expectancy varied substantially between the European countries. The lowest figures were found among Lithuanian men and women (33.1 and 39.1 years, respectively), and the highest among Italian (42.8 and 44.4, respectively). Both life expectancy and disability-free life expectancy were longer the higher the education, but educational differences were much larger in the latter in all countries. The difference between primary and lower secondary educated and tertiary educated was over 10 years for males in Lithuania and about seven years for males in Austria, Finland, France and for females in Lithuania. The difference was lowest in Italy (4 and 2 years among men and women, respectively). Conclusion Highly educated Europeans can not only expect to live longer, but also to spend these years in better health than those with lower education. However, the size of the educational difference in disability-free life expectancy varies significantly between countries. The smallest differences are found in Southern and the largest in Eastern and Northern Europe. 7 INTRODUCTION Decreasing mortality and increasing life-expectancy in most Western-European countries during the last decades is well documented.1 This, however, does not in itself mean a healthier population. In addition to the length of the life span, the more recent research and policy interest is concerned with how many years of life are lived with and without morbidity, functional disability or activity limitations. Ageing populations pose a challenge to the sustainability of the social protection system, and, especially, people with functional limitations and chronic conditions account for a significant amount of health care spending.2 Accordingly, a key issue is whether the increased life expectancy is associated with an increase or decrease in disability.3 Often these processes are measured in terms of healthy life expectancy that combines mortality and morbidity rates into a summary measure of population health that describes both the quantity and quality of life.4 Not all populations or population sub-groups uniformly enjoy the clear increase in longevity. The difference in life expectancy between Western and Eastern European countries has still been large in the past years. Also, socioeconomic differences in health and mortality have been well documented, and those with, e.g., lower education, have higher mortality5 and shorter life-expectancy.6 Most studies even suggest that these inequalities have increased.7,8 Socioeconomic differences in healthy life expectancy have also been studied to some extent. Using Finnish data Valkonen and others9 found that health expectancy depends strongly on the indicator – such as limiting long-standing illness, functional disability and poor selfperceived health – used to measure morbidity, but the patterns of differences between socioeconomic categories were largely independent of the indicators. Crimmins and Cambois10 have done a comprehensive review of articles published in the 1980s and 1990s finding a consistent general conclusion that differences by socioeconomic indicators in healthy life expectancy are larger than differences in total life expectancy irrespective of socioeconomic or health outcome indicator used. However, to our knowledge, there are no corresponding reviews with more recent data and the most recent developments in healthy life expectancies remain unknown. Cross-country comparisons of socioeconomic differences in healthy life expectancy are still few and mostly include only few countries. According to Sihvonen, Kunst, Lahelma et al.11 the size of socioeconomic differences in healthy life expectancy was on the same level in Finland and Norway. However, this similarity hides the fact that the size of inequalities was larger in mortality in Finland and in morbidity in Norway. Majer, Nusselder, Mackenbach et al.6 compared educational differences in healthy life expectancy between ages 50 and 65 years in ten Western-European countries in the latter part of the 1990s. Higher educated persons lived longer in good health in all countries, but the longest disability-free life expectancy was in Spain, and the largest absolute inequalities between educational groups were in Portugal and France. In the calculation of healthy life expectancy some studies have used activity limitation based measures as the health indicator. Activity limitation can be seen to involve not only specific diseases or basic physical functioning required for daily living like bathing, dressing and walking but also activities at the level of the person in society.4 In other words, it generally relates to the ability to care for one’s own needs independently.12 Studies on socioeconomic differences in activity limitation are few, but they suggest that social inequalities exist in several Western-European countries and in the United States according to this indicator as well.6,13 8 At the moment it is a challenge to attempt to form a coherent picture of recent levels of socioeconomic inequalities in healthy life expectancy because mostly the results from previous studies are based on various data sets using different health outcomes and socioeconomic indicators and they cover different age ranges. Especially, cross-country comparisons with more recent data are lacking entirely. This study includes eight countries from all parts of Europe, covers a broad age group of 30–79 years, uses a global and evaluated health outcome, Global Activity Limitation Indicator (GALI), and utilises comparable and harmonised mortality data from the 2000s to study educational inequalities in healthy life expectancies. METHODS Data Two kinds of data are needed to calculate the healthy life expectancies, one providing mortality rates for sex- and age-groups and one supplying the health prevalences for corresponding categories. Mortality data were collected and harmonised by the EURO-GBDSE project and covered at least the first part of the 2000s and the health indicator was acquired from the European Union Statistics on Income and Living Conditions (EU-SILC) cross sectional survey data for 2005. As a whole the EURO-GBD-SE project includes twenty-one areas in eighteen European countries, but to be included in this study several requirements were to be met. First of all, we only included those countries where mortality data were linked to census data in order to avoid numerator-denominator bias in the cross-sectional unlinked data. Secondly, we were naturally only able to involve those countries that had also taken part in the EU-SILC survey that provided the heath measure used in these analyses. Additionally, a few more limitations were done. On the grounds of e.g. an evaluation report of the measurement of education in EU-SILC,14 the measurement of education in the United Kingdom may be incorrect in the EU-SILC survey data and thus be a poor match with the mortality data. The size of the Swedish sample in EU-SILC survey was small and following the necessary exclusions based on e.g., missing data the final sample was not, according to our judgement, representative anymore. Furthermore, the Dutch data set was based on a labour force survey, so it mainly included only people aged below 65, and was thus not suitable for the research questions this study posed. These three countries were thus excluded from the final analyses. All together the eight countries (Table 1) involved in this study included over 60 million person-years and more than 508 000 deaths in the age group of 30–79 years. For Belgium, Italy and Spain census-linked mortality data were not available for the whole country but only a few areas which were Brussels in Belgium, Turin and Tuscany in Italy and Madrid and Barcelona in Spain. Education was categorised into three groups in this study: the first group includes those with primary or lower secondary education (Isced level 2 or less), the second is comprised of those with upper secondary education (Isced levels 3 and 4) and the third group involves those with tertiary education (Isced level 5 or higher as well as level 4 in Belgium). The categorisation of the education was mostly based on the harmonisation process in the EURO-GBD-SE – project, but advice was also received through personal contacts with national representatives 9 from the participating countries. For the countries included, the educational distribution seemed to match the OECD education statistics (Health at a Glance 200215) relatively well. Table 1. Years of mortality follow-up, number of person-years and deaths and distribution of person-years by education in men and women Men Number of Mortality follow-up Finland personyears deaths Women Education (%) Primary & lower secondary Upper secondary Number of Tertiary personyears deaths Education (%) Primary & lower secondary Upper secondary Tertiary 2001 - 2007 7 960 794 91 298 36.4 37.0 26.6 8 423 795 54 497 36.2 34.0 29.8 Norway Lithuania 1 2001 - 2006 2001 - 2004 6 094 049 3 128 450 48 667 59 338 18.9 26.6 55.9 57.4 25.1 16.0 6 215 418 3 867 305 34 676 37 173 23.0 26.8 52.8 55.4 24.2 17.8 1 2001 - 2004 2001 - 2002 1999 - 2005 2001 - 2003 2000 - 2006 2001 - 2006 2001 - 2005 746 697 2 347 448 773 471 2 462 802 3 478 511 1 248 229 732 860 7 323 22 954 7 932 23 529 31 269 11 217 7 263 46.9 20.8 37.4 53.8 51.3 56.6 57.4 18.4 62.3 45.0 23.2 24.2 29.0 28.9 34.7 17.0 17.6 23.0 24.5 14.4 13.7 845 277 2 524 795 853 139 2 754 156 3 909 302 1 427 896 826 171 5 567 16 736 4 338 12 998 18 343 8 019 5 000 50.5 40.8 48.0 61.7 58.3 63.8 59.9 18.8 49.8 35.3 19.4 19.2 24.4 27.9 30.7 9.4 16.7 19.0 22.5 11.8 12.3 Brussels Austria France Madrid Barcelona Turin Tuscany 1 While all other countries reported age at death, Norway and Brussels reported age at baseline and attributed deaths and person-years to the baseline age. In the EURO-GBDSE -project an adjustment method was developed in order to ensure comparability between countries that reported differently. See Appendix. The health indicator used in this study was acquired from the European Union Statistics on Income and Living Conditions (EU-SILC) cross sectional survey data for 2005. The EUSILC has been established to provide data on structural social indicators, but it also includes a few health measures. The survey is based on the idea of a common methodological framework for all EU countries, which is defined by harmonised lists of variables, common concepts and uniform classifications. The data are collected by national statistical offices or by research institutes of the participating countries. Eurostat along with the Euro-REVES and the EHEMU projects have done comprehensive work to launch a coherent indicator that measures disability across Europe. The Global Activity Limitation Indicator (GALI) which was used as the health outcome in this study, is an evaluated16,17 indicator, though so far not used in many studies or to examine socioeconomic differences. This single item instrument is based on health-related long-term limitations on daily activities. It inquires: “For the past 6 months or more have you been limited in activities people usually do because of a health problem?” There are three answer categories: “Yes, severely”, “Yes, moderately” and “No”. In this study, the category “severely limited” described disability. Sample weights were used in the analyses of the survey data. Table 2 shows the numbers of cases included in the analyses in this study by country and the proportion of participants reporting severe disability. This varied from about 5% in Italy to over 14% among Finnish women. 10 Table 2. Number of cases in the EU-SILC survey data and the proportion (%) reporting severe disability by sex Finland Norway Lithuania Belgium Austria France Spain Italy Number Men Proportion (%) reporting severe disabilty Number Women Proportion (%) reporting severe disabilty 4 183 2 240 3 208 3 369 3 839 6 711 10 119 16 325 12.6 9.0 10.3 7.3 10.0 6.1 7.7 4.7 4 194 2 252 4 013 3 526 4 148 7 352 10 933 16 917 14.4 10.3 12.0 9.3 10.1 6.3 9.6 5.3 Methods Health expectancies were calculated by Sullivan’s18 method and the standard errors needed for the calculation of the confidence intervals by the method proposed by Jagger et al. 19 using five-year age intervals. We calculated partial life expectancies between ages 30 and 79. Healthy life expectancy calculated this way demonstrates how many years men and women with different educational attainment could expect to live without long-term activity limitations between these ages. The theoretical maximum number is 50 years in a population with no mortality and morbidity. We settled on calculating partial healthy life expectancies for age-group 30–79 for two reasons. First, among those aged 80 and over, the coverage of information on education varies between countries. Typically, the proportion of observations with missing values is the higher the older the age-group is also in these mortality data sets. Secondly, at older ages the proportion of persons in institutional care increases notably and differently in different countries and as the EU-SILC data only include the household population the comparative results would be biased among the elderly. RESULTS The lowest disability-free life expectancy between ages 30 and 79 was among Lithuanian men and women (33.0 and 39.0 years, respectively), and to a large extent this was a consequence of short life expectancy (36.9 years among men and 44.5 among women) (Tables 3 & 4). Disability-free life expectancy was rather low also among the Finns, but this arose largely from the long life expectancy lived with disability (5.5 years among men and 6.6 among women). The highest figures were found among Italian men and women (disability-free life expectancy was 42.6 and 44.4 years, respectively). In all countries both life expectancy and disability-free life expectancy were longer the higher the education was. However, educational differences were much smaller in life expectancy than in disability-free life expectancy (Tables 3 & 4). The difference in life expectancy between primary & lower secondary educated and tertiary educated was smallest in Italy (2.3 years among men and 0.6 among women) and largest in Lithuania (9.2 years among men and 4.7 among women). However, the difference in disability-free life expectancy between 11 primary & lower secondary educated and tertiary educated was as high as 10.2 years among Lithuanian men and about 7 years for males in Austria, Finland and France. Among women the figures were somewhat smaller, and they were, at the largest, 7.3 years in Lithuania, 6.4 in Norway and 5.3 in Austria. The smallest differences between the educational groups were in Southern European countries. In Spain and Italy the difference in disability-free life expectancy was 4.0 and 4.6 years among Italian and Spanish men and 2.0 and 2.8 among women, respectively. Results for the life spent disability-free were slightly different. The proportions were larger in Lithuania (89.3 and 87.6% among men and women, respectively) than in Finland (87.2 and 85.8%) and among Austrian men (89.0%). The result for Lithuanian men arose as the combination of the rather short life expectancy spent with disability and extremely short life expectancy. Among primary and lower secondary educated men the proportion of life spent disability-free was the lowest in Austria (83%) and Finland (85%) and the highest in Italy (94%). Corresponding figures were much higher among the tertiary educated: almost 93% in Finland and Austria, and almost 98% in France and Italy. Among women the lowest figures (84– 85%) were found among primary and lower secondary educated in Finland, Lithuania and Norway and the highest (97.5%) among tertiary educated French. 12 Table 3. Educational differences in partial life expectancy, partial disability-free life expectancy and proportion of life spent disability-free between the age of 30 and 79 years among men Partial life expectancy between the age of 30 and 79 years Finland Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education Norway Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education Lithuania Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education Belgium (Brussels) Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education Austria Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education France Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education Spain (Madrid & Barcelona) Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education Italy (Turin & Tuscany) Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education Life expectancy Life expectancy with disability Disability-free life expectancy (95% CI for disability-free life expectancy) Proportion (%) of life spent disabilityfree 42.8 5.5 37.3 (36.9-37.8) 87.2 40.8 43.0 45.4 5.9 7.6 3.4 34.9 35.4 42.0 (34.0-35.7) (33.3-37.5) (41.1-42.8) 85.4 82.4 92.4 4.6 2.5 7.1 44.5 42.3 44.7 46.5 4.3 5.1 5.0 2.8 40.2 37.2 39.7 43.7 (39.6-40.8) (35.4-39.0) (38.8-40.5) (42.6-44.7) 90.3 87.8 88.8 93.9 4.2 2.3 6.5 36.9 32.9 37.4 42.1 3.9 4.1 4.2 3.0 33.0 28.9 33.2 39.1 (32.6-33.4) (27.6-30.1) (32.6-33.9) (38.1-40.0) 89.3 87.6 88.7 92.8 9.2 1.1 10.2 43.5 42.3 43.6 45.7 3.3 4.8 3.2 2.1 40.2 37.6 40.4 43.6 (39.7-40.6) (36.7-38.4) (39.6-41.2) (42.9-44.3) 92.3 88.7 92.7 95.4 3.4 2.7 6.0 43.3 41.7 43.3 45.5 4.8 7.3 4.6 3.2 38.5 34.5 38.7 42.3 (38.1-39.0) (33.2-35.7) (38.1-39.3) (41.4-43.2) 89.0 82.5 89.3 92.9 3.8 4.1 7.8 43.4 41.9 43.9 46.2 2.8 3.6 2.7 1.0 40.6 38.3 41.3 45.1 (40.3-40.9) (37.7-38.8) (40.8-41.8) (44.6-45.7) 93.5 91.4 94.1 97.6 4.3 2.6 6.8 44.0 43.1 44.7 45.6 3.7 4.4 3.0 2.3 40.3 38.7 41.7 43.3 (40.1-40.6) (38.4-39.0) (41.0-42.4) (42.8-43.9) 91.5 89.8 93.4 95.0 2.5 2.1 4.6 44.9 2.3 42.6 (42.4-42.8) 94.8 44.2 45.8 46.5 2.8 1.6 1.1 41.4 44.2 45.4 (41.1-41.6) (43.9-44.5) (44.5-45.9) 93.7 96.5 97.6 2.3 1.7 4.0 13 Table 4. Educational differences in partial life expectancy, partial disability-free life expectancy and proportion of life spent disability-free between the age of 30 and 79 years among women Partial life expectancy between the age of 30 and 79 years Proportion (%) of (95% CI for life spent disabilitydisability-free Life expectancy Disability-free free life expectancy) with disability life expectancy Life expectancy Finland Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education Norway Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education Lithuania Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education Belgium (Brussels) Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education Austria Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education France Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education Spain (Madrid & Barcelona) Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education Italy (Turin & Tuscany) Primary & lower secondary education Upper secondary education Tertiary education Difference between lowest and highest education 46.4 45.2 46.7 47.5 6.6 7.2 6.8 6.1 39.8 38.0 39.8 41.4 2.3 1.1 3.4 46.5 45.3 46.8 47.7 5.0 6.9 5.0 2.8 41.6 38.4 41.7 44.8 2.4 4.1 6.4 44.5 41.7 44.8 46.4 5.5 6.4 6.0 3.7 39.0 35.3 38.8 42.6 4.7 2.7 7.3 46.1 45.6 46.3 47.2 4.5 6.3 3.7 3.0 41.6 39.2 42.5 44.2 1.6 3.3 5.0 46.3 45.8 46.6 47.2 5.1 6.4 4.7 2.6 41.2 39.4 41.9 44.7 1.4 3.8 5.3 46.9 46.4 47.2 47.9 3.1 4.1 2.2 1.2 43.8 42.3 45.0 46.7 1.5 2.9 4.4 47.2 47.0 47.4 47.8 5.2 5.6 3.6 3.6 42.1 41.4 43.8 44.2 0.8 2.0 2.8 47.1 46.9 47.3 47.5 2.7 3.0 2.3 1.7 44.4 43.8 44.9 45.8 0.6 1.3 2.0 14 (39.3-40.3) (36.9-39.1) (38.8-40.9) (40.2-42.6) 85.8 84.0 85.3 87.2 (40.9-42.2) (36.6-40.2) (40.9-42.6) (43.7-46.0) 89.3 84.8 89.2 94.1 (38.5-39.4) (33.9-36.7) (38.0-39.6) (41.5-43.8) 87.6 84.6 86.6 92.0 (41.1-42.1) (38.3-40.2) (41.7-43.4) (43.1-45.3) 90.2 86.1 91.9 93.6 (40.7-41.7) (38.5-40.2) (41.2-42.6) (43.3-46.1) 89.0 86.0 89.8 94.6 (43.5-44.1) (41.8-42.8) (44.5-45.5) (46.0-47.3) 93.3 91.2 95.3 97.5 (41.8-42.4) (41.0-41.7) (42.9-44.7) (43.3-45.1) 89.1 88.0 92.4 92.6 (44.2-44.6) (43.6-44.1) (44.5-45.4) (45.0-46.6) 94.3 93.5 95.1 96.4 DISCUSSION This study compared socioeconomic differences in partial disability-free life expectancy between eight European countries in the early 2000s. Both life expectancy and disability-free life expectancy varied considerably between countries with the lowest figures in Lithuania and the highest in Italy. While the short disability-free life expectancy stemmed mostly from short life expectancy in Lithuania, it was caused by high prevalence of health-based activity limitation in some areas, notably in Finland, Austria and Norway. Still at the beginning of the 21st century highly educated Europeans can expect to live longer, and also to spend these years in better health than those with lower education. The largest educational differences in disability-free life expectancy were in Lithuania, Norway and Austria. There was, as in life-expectancy, a clear distinction between whether this was caused by socioeconomic difference in mortality or in disability: again in Lithuania differences in mortality were much more important while in Austria differences in disability were more essential. Furthermore, among women educational difference in life expectancy with disability was in most cases more important than difference in life expectancy while the opposite holds true for men. An important finding in this study was that the proportion of life spent disability-free was similar among men and women indicating that even though women live longer, they spend a larger absolute amount of time in disability. The use of a summary measure of population health instead of only one indicator – either morbidity or mortality – provides a more versatile understanding of the sex differences in health. Methodological issues We used survey data which were based on a common framework and study design and harmonised mortality data sets. By this we aimed to avoid two common, yet severe, limitations that cross-country comparisons often face, these are inter-survey differences in indicators included and differences in variable classifications.20 Furthermore, all mortality data used in this study were census-linked meaning that the death certificates were linked to census records, and, thus, information comes from one source. The reliability of the mortality data especially from the post-communist countries in the Eastern Europe has been discussed, and the overall conclusion is that the unlinked cross sectional mortality data overestimate the educational inequality in mortality as they tend to overstate mortality in disadvantaged groups and understate mortality in advantaged groups through the numerator – denumerator bias.21 The use of individual linkage of deaths to the census in the case of Lithuania in the current study removes the risk of such a bias. Life expectancies for Belgium, Italy and Spain were based on mortality data on only a few areas in these countries which were Brussels in Belgium, Turin and Tuscany in Italy and Madrid and Barcelona in Spain. The high life expectancy found especially in Italy and Spain may to some extent occur from this. It is possible that the mortality data are not representative of the whole of these countries, but represents areas with a somewhat lower than average mortality.1 However, educational differences in mortality in Turin and Tuscany are of the same magnitude as differences in Italy altogether.22 We thus believe that our results on educational differences in disability-free life expectancy are not crucially affected by the use of regional mortality data instead of national data. 15 The highest educational level attained was used as a socioeconomic status indicator in this study. As education is unlikely to change after early adulthood, morbidity in later life has less of an influence on education than it has on occupation or income. There were, however, large differences in the distribution of educational level between countries. It is possible that a selection effect is shown in the results concerning those countries where the proportion of primary educated is small, e.g. among Austrian men where not only is the per cent of primary and lower secondary education low (21%), but also life expectancy with limitations high in this group. The same health problems that cause activity limitation later in life may have prevented the accomplishment of further education earlier. The outcome measure – long-term activity limitation caused by health problems – used in this study is self-reported. This may complicate the interpretation of results in cross-country comparison studies because of cross-cultural differences in response styles. These differences have been studied in self-rated health which is probably quite a sensitive measure for these kinds of issues. According to J rges23 the differences in self-reported health between countries may thus reflect – in addition to true health differences – different reference levels of health among respondents from different cultures, different connotations response alternatives on selfreported health have or differences in the tendency to choose extreme points of the response scale. The outcome measure used in the current study, however, differs from self-rated health in some essential features. First, as a measure of morbidity and disability GALI is a more concrete measure as compared to self-rated health and is probably easier for respondents to assess similarly in various countries and contexts. Furthermore, GALI specifies disability to be long-term and detrimental enough to limit usual activities, and the response alternatives only include three categories which decreases the possibility of bias relating to national differences in extreme reporting. To further assess the reliability of the GALI, we compared results from the EU-SILC data to those from the SHARE in equivalent age groups, and found similar country-specific prevalences for severe limitation in these two data sets (results not shown). These findings suggest that the GALI is a reliable measure in cross-country comparisons. We also assessed the validity of severe disability in GALI in different educational groups by using the objective measures available in SHARE data. We compared educational differences in the probability that a person with functional disability according to an objective measure (maximum grip strength) rates him/herself severely hampered, and we found no differences between the three educational categories studied (results not shown). This seems to indicate that educational differences in self-reports of severe disability reflect true differences in functional health and that severe disability in GALI is also a valid indicator for comparative analyses of socioeconomic differentials. Such large differences in severe disability between countries that we found in this study are hardly explained only by the issues mentioned above. It is likely that also different living conditions and distinctions in contextual factors between areas affect on how limiting disability is experienced and most probably mediate it. Variety in support in everyday life that those with severe disability receive is an obvious example of such mediators. Several studies have shown that frequent contacts between elderly parents and their adult children are much more common in Southern than in Central or Northern European countries. 24 While the proportion of parents aged 65 years or over with at least one weekly face-to-face contacts 16 with a child was over 90% in Italy, it was only 64 and 76% among Finnish men and women, respectively.25 Frequent contacts are likely to indicate also assistance in everyday life which may result in experiencing limitation as less severe. Previous studies Comparing these results to previous studies is challenging because healthy life expectancies can be and have been calculated for many different age ranges. Also, many studies with no upper age limit have not paid attention to the fact that most survey data only include household population and in the older age groups the proportion of persons with disabilities in institutional care can be notable. We avoided this problem by calculating partial life expectancies for ages 30–79 when institutional care is still uncommon.26 Furthermore, several different indicators have been used to measure health. Even those studies that have used the same health indicator that was in this study (global activity limitation indicator) may differ on the ground of disability categorisation. Jagger, Gillies, Moscone et al.27 defined disability to be any activity limitation. In the 25 EU countries in 2005 an average 50-year-old man could expect to live until 67.3 years free of activity limitation, and a woman to 68.1 years. Years lived with activity limitation were 11.4 and 15.4, respectively. We, on the other hand, considered disabled only those who were severely hampered, and disability-free life expectancy was thus longer. Majer, Nusselder, Mackenbach et al.6 studied disability-free life expectancy among WesternEuropeans in the 1990s using European Community Household Panel survey data. Disability was defined as any activity limitation, and on average, disability-free life expectancy between the ages 50 and 65 was 10.1 years among highly educated men, 8.9 among those in the middle level of education and 8.0 among men with low education and 10.8, 10.0 and 8.9 years among women, respectively. To some extent these results are similar to ours. Both studies show that partial disability-free life expectancy is the highest in Spain and Italy, and that the largest differences between educational categories are found in France and Austria and among Finnish men. However, the difference in the definition of disability (any activity limitation vs. severe limitation) had an impact: the prevalence of disability was larger and the differences between both countries and educational groups were notably greater than in the current study. Similar results showing large educational differences in healthy life expectancies have also been found outside Europe. Molla and others13 used a National Health Interview Survey in the U.S. in 1998 and found that expected years with any activity limitations were 16% of the total life expectancy among 25 year old males with at least 13 years of education, but 29% among those with less than 9 years. Corresponding figures for females were 20 and 32%, respectively. As the proportion of remaining life with activity limitation increased with age educational differences diminished to some extent but were still clear among those aged 80 years. Furthermore, using Longitudinal Studies of Aging from the NCHS Hagedorn12 shows that for American men and women with less than 12 years of education there was no change in the percent of remaining life that is active across the ten year period from 1987 to 1997 while among those with longer education an increase in the proportion of expected life active existed. This implies an increase in the difference in health expectancy between the socioeconomic groups. On the other hand, this result also supports the viewpoint that increase in life expectancy is not necessarily accompanied by increase in disability or functional limitations. 17 CONCLUSION Highly educated Europeans can not only expect to live longer, but also to spend these years in better health than those with lower education. However, the size of the educational difference in disability-free life expectancy varies significantly between countries. The smallest differences are found in Southern and the largest in Eastern and Northern Europe. ACKNOWLEDGEMENTS The authors would like to thank Dalia Ambrozaitiene (Statistics Lithuania), Vlada Stankuniene (Institute for Demographic Research, Lithuania), Dmitri A. Jdanov (Max Planck Institute for Demographic Research, Germany), and Vladimir M. Shkolnikov (Max Planck Institute for Demographic Research, Germany) for their contributions to the census-linked dataset for Lithuania. APPENDIX For most countries persons were allowed to age during the mortality follow-up so that each death and person-year was attributed to the age of the individual at the time. However, Norway and Brussels reported only age at baseline and attributed all deaths and person-years to the baseline age. In the EURO-GBD-SE -project an adjustment method was developed in order to ensure comparability between countries that reported differently. The adjustment method can be described as the following: where is the estimated death risk in the ith age interval, Mxi is the observed death risk, 2 is a coefficient describing the relationship between ln(Mxi ) and xi , s is a constant estimating the size of the bias, based on the length of follow-up and xi is age interval. The adjustment method is based on the roughly linear relationship between age and ln death risk in adult populations. For more details, see EURO-GBD-SE working document.28 18 REFERENCES 1. Eurostat. 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