Taiwan – Biodemography of Health, Social Factors, and Life Challenge
SEBAS – Social Environment and Biomarkers of Aging Study
Demographic processes, the social environment, and life challenge are intimately interlocked with functional status and illness. The social environment, encompassing position in social hierarchies as well as linkages within social networks and support systems, interacts with exposure to challenge to influence physical and mental wellbeing.
The Social Environment and Biomarkers of Aging Study (SEBAS) in Taiwan was initially developed to explore how understanding the relationships among life challenge, the social environment, and health can be enhanced by incorporating biological markers of health and stress. Specific aims of the initial study included:
1. Investigating the extent to which biological markers of stress and chronic illness are related to reports of life events;
2. Examining the extent to which biological markers help to explain variation in health across social hierarchies and networks; and
3. Exploring the associations among the biological markers, data from physicians’ examinations, and self-reported health status, and their links to survival.
With the addition of longitudinal data, the goals of the project have expanded to understanding the antecedents, correlates, and consequences of levels and changes in biological measures, health and survival.Cornman et al., 2014,
Click here to view the Cohort Profile in the International Journal of Epidemiology.
SEBAS comprises a nationally representative longitudinal survey of Taiwanese adults age 54 and over.
It adds the collection of biomarkers and performance assessments to the Taiwan Longitudinal Study of Aging (TLSA), a nationally representative study of adults age 60 and over, including the institutionalized population. The TLSA began in 1989 with follow-ups approximately every three years; younger refresher cohorts were added in 1996 and 2003. The first wave of SEBAS, based on a sub-sample of respondents from the 1999 TLSA, was conducted in 2000. A total of 1023 respondents completed both a face-to-face home interview and, several weeks later, a hospital-based physical exam. In addition to a 12-hour (7pm-7am) urine specimen collected the night before the exam and a fasting blood specimen during the exam, trained staff measured blood pressure, height, weight, waist, and hip circumference. A second wave of SEBAS was conducted in 2006 using a similar protocol to SEBAS 2000, but with the addition of performance assessments conducted by the interviewers at the end of the home interview.Cornman et al., 2014
The interlocking architecture of the TLSA and SEBAS surveys is shown in Figure 1.
Both waves of SEBAS also included measures of health status (physical, emotional, cognitive), health behaviors, social relationships, and exposure to stressors. The SEBAS data, which are publicly available from the ICPSR, allow researchers to explore the relationships among life challenge, the social environment, and health and to examine the antecedents, correlates, and consequences of change in biological measures and health .Cornman et al., 2014
First Wave (SEBAS 2000)
The first wave of SEBAS, based on a sub-sample of respondents from the 1999 TLSA, was conducted in 2000″ and represented a national sample of Taiwanese adults aged 54 and older. Like TLSA, it included an in-home interview, but was supplemented by collection of biomarkers. “A total of 1023 respondents completed both a face-to-face home interview and, several weeks later, a hospital-based physical exam.Cornman et al., 2014
Second Wave (SEBAS 2006)
A second wave of SEBAS was conducted in 2006 using a similar protocol to SEBAS 2000, but with the addition of performance assessments conducted by the interviewers at the end of the home interview…The targeted sample included the 1023 respondents who had completed both the home interview and the health exam in 2000 as well as a refresher cohort of 660 respondents aged 53-60 in 2006 who were first interviewed in the 2003 TLSA. Thus, the 2006 SEBAS comprised a representative cross-section of the Taiwanese population aged 53 and older. The 2006 in-home interview was completed by 1284 respondents, 1036 of whom also participated in the physical exam.(Cornman et al., 2014)
Table 1 lists selected measures collected in TLSA and SEBAS. “Both waves of SEBAS included measures of health status (physical, emotional, cognitive), health behaviors, social relationships, and exposure to stressors” (Cornman et al., 2014) based on the in-home interview. Data from the hospital visit include anthropometry, blood pressure, and laboratory assays of fasting blood and 12 hr overnight urine specimens. “Comparisons of the laboratory assay results for duplicate specimens sent to the lab in Taiwan (Union Clinical Laboratory) indicate high intra-lab correlations (>= 0.9) for most markers tested, with a few notable exceptions (e.g., IGF-1, sICAM-1). Based on comparisons with results from a lab in the U.S. (Quest Diagnostics), inter-lab correlations were also generally high (>= 0.9). For details, see Table 2.2 in the “SEBAS User Guide.” (Cornman et al., 2014) The DNA specimens have already been assayed for APOE, 5-HTTLPR, and telomere length. An additional 164 targeted genes and single nucleotide polymorphisms (SNPs) are currently being processed. See Table 2 for a full list.
Perhaps the most notable strength of the data is the detail and breadth of the available indicators related to health, the social environment, and life challenges. First, the data contain an unusually large array of biological markers, including several genetic markers. Current work includes assays for additional genes and SNPs; the public use data file will be updated for these markers when the work is complete. Second, self-reported measures cover multiple dimensions of health status (physical, emotional, and cognitive); several health-related behaviors; and use of biomedical and traditional health-care facilities and providers. Third, interviewer-administered health assessments offer yet another method for evaluating the respondent’s health. Fourth, the data include high quality information for determining survival status. Finally, SEBAS includes indicators of both objective and subjective socioeconomic status, social relationships, and exposure to stressors ranging from daily hassles to trauma. Other strengths include a relatively large, nationally-representative sample; an age range that includes persons as young as 53; high participation rates; and longitudinal follow-up with low loss to follow-up. Nonetheless, the data also have limitations. As with any study of an older population, those who died at relatively early ages are not represented; yet, the proportion of the Taiwanese population dying before age 53 is small: 7.5% in 2006 (Human Mortality Database, accessed April 2, 2014). (Cornman et al., 2014)
How to Obtain Access to the Data
A public use dataset and full documentation for the biomarker study are available from the ICPSR (persistent URL: doi.org/10.3886/ICPSR03792.v7). “The dataset includes information from the: a) 2000 SEBAS for the N = 1023 respondents who completed the home interview and the physical exam; and
b) 2006 SEBAS for the N = 1284 respondents who completed the home interview (including clinical data for those who also participated in the exam: N = 1036).” (Cornman et al., 2014)
Data from the 2000 and 2006 rounds of SEBAS can be downloaded from the ICPSR at: https://www.icpsr.umich.edu/icpsrweb/NACDA/studies/3792. The website notes that “Users are advised that the data in this collection are restricted and available only by special arrangement with the staff of the National Archive of Computerized Data on Aging (NACDA) at ICPSR. These requirements are part of the arrangements governing the release of data assembled under this project which stipulate that the data must be used solely for social and behavioral science research. The data and other materials are to be used only for statistical analysis and reporting of aggregated information, and not for the investigation of specific individuals or organizations. Users interested in obtaining and using these data must request and complete a Restricted Data Use Agreement form indicating that: (1) she/he understands the need to protect the data, and (2) she/he will use the data for research purposes only. Users can download this form from the download page associated with this dataset. Completed forms with original signature(s) should be emailed to email@example.com.”
Other data (i.e., 2011 or 2016 SEBAS waves, TLSA waves) can be requested from the Health Promotion Administration, at the Ministry of Health and Welfare in Taiwan (contact person: Yu-Hsuan Lin, firstname.lastname@example.org).
The Social Environment and Biomarkers of Aging Study (SEBAS) presented June 20, 2016. Access the webinar here: https://www.youtube.com/watch?v=vCDmbMNEVuc&feature=youtu.be
Cornman, J.C., D.A. Glei, N. Goldman, M-C. Chang, H-S. Lin, Y-L. Chuang, B-S. Hurng, Y-H. Lin, S-H. Lin, I-W. Liu, H-Y. Liu, M. Weinstein. (2014). Cohort Profile: The Social Environment and Biomarkers of Aging Study (SEBAS) in Taiwan. International Journal of Epidemiology.
(last updated: 4 August, 2020)