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Tollman, Stephen M.
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Publications (10 of 144) Show all publications
Byass, P., Hussain-Alkhateeb, L., D'Ambruoso, L., Clark, S., Davies, J., Fottrell, E., . . . Petzold, M. (2019). An integrated approach to processing WHO-2016 verbal autopsy data: the InterVA-5 model. BMC Medicine, 17, Article ID 102.
Open this publication in new window or tab >>An integrated approach to processing WHO-2016 verbal autopsy data: the InterVA-5 model
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2019 (English)In: BMC Medicine, ISSN 1741-7015, E-ISSN 1741-7015, Vol. 17, article id 102Article in journal (Refereed) Published
Abstract [en]

Background: Verbal autopsy is an increasingly important methodology for assigning causes to otherwise uncertified deaths, which amount to around 50% of global mortality and cause much uncertainty for health planning. The World Health Organization sets international standards for the structure of verbal autopsy interviews and for cause categories that can reasonably be derived from verbal autopsy data. In addition, computer models are needed to efficiently process large quantities of verbal autopsy interviews to assign causes of death in a standardised manner. Here, we present the InterVA-5 model, developed to align with the WHO-2016 verbal autopsy standard. This is a harmonising model that can process input data from WHO-2016, as well as earlier WHO-2012 and Tariff-2 formats, to generate standardised cause-specific mortality profiles for diverse contexts.

The software development involved building on the earlier InterVA-4 model, and the expanded knowledge base required for InterVA-5 was informed by analyses from a training dataset drawn from the Population Health Metrics Research Collaboration verbal autopsy reference dataset, as well as expert input.

Results: The new model was evaluated against a test dataset of 6130 cases from the Population Health Metrics Research Collaboration and 4009 cases from the Afghanistan National Mortality Survey dataset. Both of these sources contained around three quarters of the input items from the WHO-2016, WHO-2012 and Tariff-2 formats. Cause-specific mortality fractions across all applicable WHO cause categories were compared between causes assigned in participating tertiary hospitals and InterVA-5 in the test dataset, with concordance correlation coefficients of 0.92 for children and 0.86 for adults.

The InterVA-5 model’s capacity to handle different input formats was evaluated in the Afghanistan dataset, with concordance correlation coefficients of 0.97 and 0.96 between the WHO-2016 and the WHO-2012 format for children and adults respectively, and 0.92 and 0.87 between the WHO-2016 and the Tariff-2 format respectively.

Conclusions: Despite the inherent difficulties of determining “truth” in assigning cause of death, these findings suggest that the InterVA-5 model performs well and succeeds in harmonising across a range of input formats. As more primary data collected under WHO-2016 become available, it is likely that InterVA-5 will undergo minor re-versioning in the light of practical experience. The model is an important resource for measuring and evaluating cause-specific mortality globally.

Place, publisher, year, edition, pages
BioMed Central, 2019
Keywords
Verbal autopsy, Mortality surveillance, Civil registration, InterVA, Cause of death, World Health Organization
National Category
Public Health, Global Health, Social Medicine and Epidemiology
Identifiers
urn:nbn:se:umu:diva-160291 (URN)10.1186/s12916-019-1333-6 (DOI)000469778700001 ()31146736 (PubMedID)
Available from: 2019-06-17 Created: 2019-06-17 Last updated: 2019-06-17Bibliographically approved
Geldsetzer, P., Vaikath, M., Wagner, R., Rohr, J. K., Montana, L., Gomez-Olive, F. X., . . . Berkman, L. F. (2019). Depressive Symptoms and Their Relation to Age and Chronic Diseases Among Middle-Aged and Older Adults in Rural South Africa. The journals of gerontology. Series A, Biological sciences and medical sciences, 74(6), 957-963
Open this publication in new window or tab >>Depressive Symptoms and Their Relation to Age and Chronic Diseases Among Middle-Aged and Older Adults in Rural South Africa
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2019 (English)In: The journals of gerontology. Series A, Biological sciences and medical sciences, ISSN 1079-5006, E-ISSN 1758-535X, Vol. 74, no 6, p. 957-963Article in journal (Refereed) Published
Abstract [en]

Background: Understanding how depression is associated with chronic conditions and sociodemographic characteristics can inform the design and effective targeting of depression screening and care interventions. In this study, we present some of the first evidence from sub-Saharan Africa on the association between depressive symptoms and a range of chronic conditions (diabetes, HIV, hypertension, and obesity) as well as sociodemographic characteristics. Methods: A questionnaire was administered to a population-based simple random sample of 5,059 adults aged 40 years and older in Agincourt, South Africa. Depressive symptoms were measured using a modified version of the eight-item Center for Epidemiological Studies-Depression screening tool. Diabetes was assessed using a capillary blood glucose measurement and HIV using a dried blood spot. Results: 17.0% (95% confidence interval: 15.9%-18.1%) of participants had at least three depressive symptoms. None of the chronic conditions were significantly associated with depressive symptoms in multivariable regressions. Older age was the strongest correlate of depressive symptoms with those aged 80 years and older having on average 0.63 (95% confidence interval: 0.40-0.86; p<.001) more depressive symptoms than those aged 40-49 years. Household wealth quintile and education were not significant correlates. Conclusions: This study provides some evidence that the positive associations of depression with diabetes, HIV, hypertension, and obesity that are commonly reported in high-income settings might not exist in rural South Africa. Our finding that increasing age is strongly associated with depressive symptoms suggests that there is a particularly high need for depression screening and treatment among the elderly adults in rural South Africa.

Place, publisher, year, edition, pages
OXFORD UNIV PRESS INC, 2019
Keywords
Depression, South Africa, chronic diseases
National Category
Gerontology, specialising in Medical and Health Sciences
Identifiers
urn:nbn:se:umu:diva-162019 (URN)10.1093/gerona/gly145 (DOI)000475713200028 ()29939214 (PubMedID)
Available from: 2019-08-12 Created: 2019-08-12 Last updated: 2019-08-12Bibliographically approved
Kobayashi, L. C., Berkman, L. F., Wagner, R. G., Kahn, K., Tollman, S. M. & Subramanian, S. V. (2019). Education modifies the relationship between height and cognitive function in a cross-sectional population-based study of older adults in Rural South Africa. European Journal of Epidemiology, 34(2), 131-139
Open this publication in new window or tab >>Education modifies the relationship between height and cognitive function in a cross-sectional population-based study of older adults in Rural South Africa
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2019 (English)In: European Journal of Epidemiology, ISSN 0393-2990, E-ISSN 1573-7284, Vol. 34, no 2, p. 131-139Article in journal (Refereed) Published
Abstract [en]

We aimed to estimate the relationship between height (a measure of early-life cumulative net nutrition) and later-life cognitive function among older rural South African adults, and whether education modified this relationship. Data were from baseline in-person interviews with 5059 adults40years in the population-based Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI) study in Agincourt sub-district, South Africa, in 2015. Linear regression was used to estimate the relationship between height quintile and latent cognitive function z-score (representing episodic memory, time orientation, and numeracy), with adjustment for life course covariates and a height-by-education interaction. Mean (SD) height was 162.7 (8.9) cm. Nearly half the sample had no formal education (46%; 2307/5059). Mean age- and sex-adjusted cognitive z-scores increased from -0.68 (95% CI: -0.76 to -0.61) in those with no education in the shortest height quintile to 0.62 (95% CI: 0.52-0.71) in those with at least 8years of education in the tallest height quintile. There was a linear height disparity in cognitive z-scores for those with no formal education (adjusted =0.10; 95% CI: 0.08-0.13 per height quintile), but no height disparity in cognitive z-scores in those with any level of education. Short stature is associated with poor cognitive function and may be a risk factor for cognitive impairment among older adults living in rural South Africa. The height disparity in cognitive function was negated for older adults who had any level of education.

Place, publisher, year, edition, pages
Springer, 2019
Keywords
Cognitive function, Older adults, Education, Height, South Africa
National Category
Public Health, Global Health, Social Medicine and Epidemiology
Identifiers
urn:nbn:se:umu:diva-156891 (URN)10.1007/s10654-018-0453-1 (DOI)000458429900005 ()30306424 (PubMedID)
Available from: 2019-03-11 Created: 2019-03-11 Last updated: 2019-03-20Bibliographically approved
Gómez-Olivé, F. X., Montana, L., Wagner, R. G., Kabudula, C. W., Rohr, J. K., Kahn, K., . . . Berkman, L. (2018). Cohort Profile: Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI). International Journal of Epidemiology, 47(3), 689-690j
Open this publication in new window or tab >>Cohort Profile: Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI)
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2018 (English)In: International Journal of Epidemiology, ISSN 0300-5771, E-ISSN 1464-3685, Vol. 47, no 3, p. 689-690jArticle in journal (Refereed) Published
Place, publisher, year, edition, pages
Oxford University Press, 2018
National Category
Public Health, Global Health, Social Medicine and Epidemiology
Identifiers
urn:nbn:se:umu:diva-150393 (URN)10.1093/ije/dyx247 (DOI)000438342200005 ()29325152 (PubMedID)
Available from: 2018-08-06 Created: 2018-08-06 Last updated: 2018-08-06Bibliographically approved
Pettifor, A., Lippman, S. A., Gottert, A., Suchindran, C. M., Selin, A., Peacock, D., . . . MacPhail, C. (2018). Community mobilization to modify harmful gender norms and reduce HIV risk: results from a community cluster randomized trial in South Africa. Journal of the International AIDS Society, 21(7), Article ID e25134.
Open this publication in new window or tab >>Community mobilization to modify harmful gender norms and reduce HIV risk: results from a community cluster randomized trial in South Africa
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2018 (English)In: Journal of the International AIDS Society, ISSN 1758-2652, E-ISSN 1758-2652, Vol. 21, no 7, article id e25134Article in journal (Refereed) Published
Abstract [en]

Introduction: Community mobilization (CM) is increasingly recognized as critical to generating changes in social norms and behaviours needed to achieve reductions in HIV. We conducted a CM intervention to modify negative gender norms, particularly among men, in order to reduce associated HIV risk.

Methods: Twenty two villages in the Agincourt Health and Socio-Demographic Surveillance Site in rural Mpumalanga, South Africa were randomized to either a theory-based, gender transformative, CM intervention or no intervention. Two cross-sectional, population-based surveys were conducted in 2012 (pre-intervention, n = 600 women; n = 581 men) and 2014 (pos-tintervention, n = 600 women; n = 575 men) among adults ages 18 to 35 years. We used an intent-to-treat (ITT) approach using survey regression cluster-adjusted standard errors to determine the intervention effect by trial arm on gender norms, measured using the Gender Equitable Mens Scale (GEMS), and secondary behavioural outcomes.

Results: Among men, there was a significant 2.7 point increase (Beta Coefficient 95% CI: 0.62, 4.78, p = 0.01) in GEMS between those in intervention compared to control communities. We did not observe a significant difference in GEMS scores for women by trial arm. Among men and women in intervention communities, we did not observe significant differences in perpetration of intimate partner violence (IPV), condom use at last sex or hazardous drinking compared to control communities. The number of sex partners in the past 12 months (AOR 0.29, 95% CI 0.11 to 0.77) were significantly lower in women in intervention communities compared to control communities and IPV victimization was lower among women in intervention communities, but the reduction was not statistically significant (AOR 0.53, 95% CI 0.24 to 1.16).

Conclusion: Community mobilization can reduce negative gender norms among men and has the potential to create environments that are more supportive of preventing IPV and reducing HIV risk behaviour. Nevertheless, we did not observe that changes in attitudes towards gender norms resulted in desired changes in risk behaviours suggesting that more time may be necessary to change behaviour or that the intervention may need to address behaviours more directly.

Place, publisher, year, edition, pages
John Wiley & Sons, 2018
Keywords
HIV, community mobilization, gender norms, South Africa, gender-based violence
National Category
Public Health, Global Health, Social Medicine and Epidemiology
Identifiers
urn:nbn:se:umu:diva-150729 (URN)10.1002/jia2.25134 (DOI)000437681700001 ()29972287 (PubMedID)2-s2.0-85050811112 (Scopus ID)
Available from: 2018-08-28 Created: 2018-08-28 Last updated: 2018-08-28Bibliographically approved
Payne, C. F., Davies, J. I., Gomez-Olive, F. X., Hands, K. J., Kahn, K., Kobayashi, L. C., . . . Witham, M. D. (2018). Cross-sectional relationship between haemoglobin concentration and measures of physical and cognitive function in an older rural South African population. Journal of Epidemiology and Community Health, 72(9), 796-802
Open this publication in new window or tab >>Cross-sectional relationship between haemoglobin concentration and measures of physical and cognitive function in an older rural South African population
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2018 (English)In: Journal of Epidemiology and Community Health, ISSN 0143-005X, E-ISSN 1470-2738, Vol. 72, no 9, p. 796-802Article in journal (Refereed) Published
Abstract [en]

Background: Age cohort differences in haemoglobin concentrations and associations with physical and cognitive performance among populations of lower income and middle-income countries have not previously been described. We examined the association between these factors among older men and women in rural South Africa.

Methods: We analysed cross-sectional data from a population-based study of rural South African men and women aged 40 and over (n=4499), with data drawn from questionnaire responses, a cognitive battery, objective physical function tests and blood tests. Anaemia was defined as a haemoglobin concentration <12 g/dL for women and <13 g/dL for men. We related haemoglobin concentrations to each of age, grip strength, walk speed and a latent cognitive function z-score for men and women separately. We used unadjusted correlations and linear models to adjust for comorbidities and inflammation.

Results: In total, 1042 (43.0%) women and 833 (40.1%) men were anaemic. Haemoglobin concentrations were inversely correlated with age for men but not for women; in adjusted analyses, haemoglobin was 0.3 g/dL lower per decade older for men (95% CI 0.2 to 0.4 g/dL). In adjusted analyses, haemoglobin concentration was independently associated with grip strength in women (B=0.391, 95% CI 0.177 to 0.605), but this did not reach significance in men (B=0.266, 95% CI -0.019 to 0.552); no associations were observed between haemoglobin levels and walk speed or cognitive score.

Conclusions: Anaemia was prevalent in this study population of middle-aged and older, rural South African adults, but in contrast to high-income countries, it was not associated with poor physical or cognitive function. Our findings need to be replicated in other populations.

Place, publisher, year, edition, pages
BMJ Publishing Group Ltd, 2018
National Category
Public Health, Global Health, Social Medicine and Epidemiology
Identifiers
urn:nbn:se:umu:diva-152413 (URN)10.1136/jech-2018-210449 (DOI)000445084200007 ()29680801 (PubMedID)
Available from: 2018-10-05 Created: 2018-10-05 Last updated: 2018-10-05Bibliographically approved
Rosenberg, M., Pettifor, A., Twine, R., Hughes, J. P., Gomez-Olive, F. X., Wagner, R. G., . . . Kahn, K. (2018). Evidence for sample selection effect and Hawthorne effect in behavioural HIV prevention trial among young women in a rural South African community. BMJ Open, 8(1), Article ID e019167.
Open this publication in new window or tab >>Evidence for sample selection effect and Hawthorne effect in behavioural HIV prevention trial among young women in a rural South African community
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2018 (English)In: BMJ Open, ISSN 2044-6055, E-ISSN 2044-6055, Vol. 8, no 1, article id e019167Article in journal (Refereed) Published
Abstract [en]

Objectives: We examined the potential influence of both sample selection effects and Hawthorne effects in the behavioural HIV Prevention Trial Network 068 study, designed to examine whether cash transfers conditional on school attendance reduce HIV acquisition in young South African women. We explored whether school enrolment among study participants differed from the underlying population, and whether differences existed at baseline (sample selection effect) or arose during study participation (Hawthorne effect).

Methods: We constructed a cohort of 3889 young women aged 11-20 years using data from the Agincourt Health and socio-Demographic Surveillance System. We compared school enrolment in 2011 (trial start) and 2015 (trial end) between those who did (n=1720) and did not (11=2169) enrol in the trial. To isolate the Hawthorne effect, we restricted the cohort to those enrolled in school in 2011.

Results: In 2011, trial participants were already more likely to be enrolled in school (99%) compared with non-participants (93%). However, this association was attenuated with covariate adjustment (adjusted risk difference (aRD) (95% Cl): 2.9 (0.7 to 6.5)). Restricting to those enrolled in school in 2011, trial participants were also more likely to be enrolled in school in 2015 (aRD (95% Cl): 4.9 (1.5 to 8.3)). The strength of associations increased with age.

Conclusions: Trial participants across both study arms were more likely to be enrolled in school than nonparticipants. Our findings suggest that both sample selection and Hawthorne effects may have diminished the differences in school enrolment between study arms, a plausible explanation for the null trial findings. The Hawthorne-specific findings generate hypotheses for how to structure school retention interventions to prevent HIV.

Place, publisher, year, edition, pages
BMJ Publishing Group Ltd, 2018
National Category
Public Health, Global Health, Social Medicine and Epidemiology
Identifiers
urn:nbn:se:umu:diva-148036 (URN)10.1136/bmjopen-2017-019167 (DOI)000431743500200 ()29326192 (PubMedID)
Available from: 2018-05-30 Created: 2018-05-30 Last updated: 2018-06-09Bibliographically approved
Rosenberg, M., Pettifor, A., Duta, M., Demeyere, N., Wagner, R. G., Selin, A., . . . Kahn, K. (2018). Executive function associated with sexual risk in young South African women: Findings from the HPTN 068 cohort. PLoS ONE, 13(4), Article ID e0195217.
Open this publication in new window or tab >>Executive function associated with sexual risk in young South African women: Findings from the HPTN 068 cohort
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2018 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 13, no 4, article id e0195217Article in journal (Refereed) Published
Abstract [en]

Purpose Heightened sexual risk in adolescence and young adulthood may be partially explained by deficits in executive functioning, the set of cognitive processes used to make reasoned decisions. However, the association between executive function and sexual risk is understudied among adolescent girls and young women, particularly in low- and middle-income countries. Methods In a cohort of 853 young women age 18-25 in rural Mpumalanga province, South Africa, we evaluated executive function with three non-verbal cognitive tests: I. a rule-finding test, II. a trail-making test, and III. a figure drawing test. Using log-binomial regression models, we estimated the association between lower executive function test scores and indicators of sexual risk (unprotected sex acts, concurrent partnerships, transactional sex, and recent HSV-2 infection). Results In general, young women with lower executive function scores reported higher frequencies of sexual risk outcomes, though associations tended to be small with wide confidence intervals. Testing in the lowest quintile of Test I was associated with more unprotected sex [aPR (95% CI): 1.4 (1.0, 1.8)]. Testing in the lowest quintile of Test II was associated with more concurrent relationships and transactional sex [aPR (95% CI): 1.6 (1.1, 2.5) and 1.7 (1.3, 2.4), respectively], and testing in the lowest four quintiles of Test III was associated with more concurrent relationships [aPR (95% CI): 1.7 (1.0, 2.7)]. Conclusions These results demonstrate an association between low executive function and sexual risk in South African young women. Future work should seek to understand the nature of this association and whether there is promise in developing interventions to enhance executive function to reduce sexual risk.

Place, publisher, year, edition, pages
Public Library of Science, 2018
National Category
Public Health, Global Health, Social Medicine and Epidemiology
Identifiers
urn:nbn:se:umu:diva-148633 (URN)10.1371/journal.pone.0195217 (DOI)000428988800039 ()29608615 (PubMedID)2-s2.0-85044856588 (Scopus ID)
Available from: 2018-06-26 Created: 2018-06-26 Last updated: 2018-06-26Bibliographically approved
Said-Mohamed, R., Prioreschi, A., Nyati, L. H., van Heerden, A., Munthali, R. J., Kahn, K., . . . Norris, S. A. (2018). Rural-urban variations in age at menarche, adult height, leg-length and abdominal adiposity in black South African women in transitioning South Africa. Annals of Human Biology, 45(2), 123-132
Open this publication in new window or tab >>Rural-urban variations in age at menarche, adult height, leg-length and abdominal adiposity in black South African women in transitioning South Africa
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2018 (English)In: Annals of Human Biology, ISSN 0301-4460, E-ISSN 1464-5033, Vol. 45, no 2, p. 123-132Article in journal (Refereed) Published
Abstract [en]

Background: The pre-pubertal socioeconomic environment may be an important determinant of age at menarche, adult height, body proportions and adiposity: traits closely linked to adolescent and adult health.

Aims: This study explored differences in age at menarche, adult height, relative leg-length and waist circumference between rural and urban black South African young adult women, who are at different stages of the nutrition and epidemiologic transitions.

Subjects and methods: We compared 18-23 year-old black South African women, 482 urban-dwelling from Soweto and 509 from the rural Mpumalanga province. Age at menarche, obstetric history and household socio-demographic and economic information were recorded using interview-administered questionnaires. Height, sitting-height, hip and waist circumference were measured using standardised techniques.

Results: Urban and rural black South African women differed in their age at menarche (at ages 12.7 and 14.5 years, respectively). In urban women, a one-year increase in age at menarche was associated with a 0.65 cm and 0.16% increase in height and relative leg-length ratio, respectively. In both settings, earlier age at menarche and shorter relative leg-length were independently associated with an increase in waist circumference.

Conclusions: In black South African women, the earlier onset of puberty, and consequently an earlier growth cessation process, may lead to central fat mass accumulation in adulthood.

Place, publisher, year, edition, pages
Taylor & Francis, 2018
Keywords
Age at menarche, height, body proportions, adiposity, nutrition transition
National Category
Public Health, Global Health, Social Medicine and Epidemiology
Identifiers
urn:nbn:se:umu:diva-152140 (URN)10.1080/03014460.2018.1442497 (DOI)000430599600004 ()29557678 (PubMedID)
Available from: 2018-10-01 Created: 2018-10-01 Last updated: 2018-10-01Bibliographically approved
Houle, B., Mojola, S. A., Angotti, N., Schatz, E., Gomez-Olive, F. X., Clark, S. J., . . . Menken, J. (2018). Sexual behavior and HIV risk across the life course in rural South Africa: trends and comparisons. AIDS Care, 30(11), 1435-1443
Open this publication in new window or tab >>Sexual behavior and HIV risk across the life course in rural South Africa: trends and comparisons
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2018 (English)In: AIDS Care, ISSN 0954-0121, E-ISSN 1360-0451, Vol. 30, no 11, p. 1435-1443Article in journal (Refereed) Published
Abstract [en]

There is limited information about sexual behavior among older Africans, which is problematic given high HIV rates among older adults. We use a population-based survey among people aged 15-80+ to examine the prevalence of sexual risk and protective behaviors in the context of a severe HIV epidemic. We focus on variation across the life course, gender and HIV serostatus to compare the similarities and differences of young, middle aged, and older adults. Younger adults continue to be at risk of HIV, with potential partners being more likely to have been diagnosed with an STI and more likely to have HIV, partner change is high, and condom use is low. Middle aged and older adults engage in sexual behavior that makes them vulnerable at older ages, including extramarital sex, low condom use, and cross-generational sex with people in age groups with the highest rates of HIV. We find insignificant differences between HIV positive and negative adults' reports of recent sexual activity. This study provides new information on sexual behavior and HIV risk across the life course in rural South Africa to inform HIV prevention and treatment programing.

Place, publisher, year, edition, pages
ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD, 2018
Keywords
Sexual behavior, life course, South Africa, HIV, AIDS
National Category
Public Health, Global Health, Social Medicine and Epidemiology
Identifiers
urn:nbn:se:umu:diva-153846 (URN)10.1080/09540121.2018.1468008 (DOI)000445239600015 ()29701073 (PubMedID)
Available from: 2018-12-06 Created: 2018-12-06 Last updated: 2018-12-06Bibliographically approved
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