Birt efni

Rannsókn við Háskóla Íslands

Birtar vísindagreinar þann 1. febrúar 2022

Soffia M. Hrafnkelsdottir, Robert J. Brychta, Vaka Rognvaldsdottir, Kong Y. Chen, Erlingur Johannsson, Sigridur L. Guðmundsdottir, Sigurbjorn A. Arngrimsson. (2022). Screen Time and Body Image in Icelandic Adolescents: Sex-Specific Cross-Sectional and Longitudinal Associations.

Runa Stefansdottir, Vaka Rognvaldsdottir, Kong Y. Chen, Erlingur Johannsson, Robert J. Brychta. (2021). Sleep timing and consistency are associated with the standardised test performance of Icelandic adolescents.

Stefansdottir, R., Gundersen, H., Rognvaldsdottir, V., Lundervold, A. S., Gestsdottir, S., Gudmundsdottir, S. L., … & Johannsson, E. (2020). Association between free-living sleep and memory and attention in healthy adolescents. Scientific reports, 10(1), 1-13.

Runa Stefansdottir, Vaka Rognvaldsdottir, Kong Y. Chen, Erlingur Johannsson, Robert J. Brychta. Sleep timing, duration, and consistency are associated with the standardized test performance of Icelandic adolescents. J Sleep Res. 2021 Jun 14:e13422. doi: 10.1111/jsr.13422. Online ahead of print. PMID: 34128282

Saevarsson ES, Rognvaldsdottir V, Stefansdottir R, Johannsson E. Organized Sport Participation, Physical Activity, Sleep and Screen Time in 16-Year-Old Adolescents. Int J Environ Res Public Health. 2021 Mar 18;18(6):3162.

Gunnarsdottir B, Hrafnkelsson H, Johannsson E, Sigurðsson EL. [Vitamin D status of Icelandic children and youngsters: Longitudinal study. Laeknabladid. 2020 May;106(5):235-240.

Hrafnkelsdottir, S. M., Brychta, R. J., Rognvaldsdottir, V., Chen, K. Y., Johannsson, E., Gudmundsdottir, S. L., & Arngrimsson, S. A. (2020). Less screen time and more physical activity is associated with more stable sleep patterns among Icelandic adolescents. Sleep health, 6(5), 609-617.

Gudmundsdottir SL, Hrafnkelsson H, Sigurdsson EL, Johannsson E. Serum 25-hydroxyvitamin D concentrations in 16 year old Icelandic adolescents and its association with bone mineral density. Pub Health Nutr. 2020 (samþykkt til birtingar)

Brychta RJ, Rögnvaldsdóttir V, Guðmundsdóttir SL, Stefánsdóttir R, Hrafnkelsdóttir SM, Gestsdóttir S, Arngrímsson SA, Chen KY, Jóhannsson E. Longitudinal Change in Adolescent Bedtimes Measured by Self-Report and Actigraphy. J Meas Phys Behav. 2019 Dec;2(4):282-287.

Saevarsson E, Svansdottir E, Arngrimsson S, Sveinsson T, Johannsson E. Different cardiorespiratory fitness expressions based on the maximal cycle ergometer test show no effect on the relation of cardiorespiratory fitness to the academic achievement of nine-year-olds. PLoS One. 2018 Jul 23;13(7)

Rognvaldsdottir V, Valdimarsdottir BM, Brychta RJ, Hrafnkelsdottir SM, Arngrimsson SA, Johannsson E, Chen KY, Gudmundsdottir SL. Physical activity and sleep in Icelandic adolescents. Laeknabladid. 2018 Feb;104(2):79-85.

Hrafnkelsdottir SM, Brychta RJ, Rognvaldsdottir V, Gestsdottir S, Chen KY, Johannsson E, Guðmundsdottir SL, Arngrimsson SA. Less screen time and more frequent vigorous physical activity is associated with lower risk of reporting negative mental health symptoms among Icelandic adolescents. PLoS One. 2018 Apr 26;13(4).

Hannesdóttir Þ, Hrafnkelsson H, Johannsson E, Sigurdsson E. Tengsl D-vítamíns og áhættuþátta hjarta- og æðasjúkdóma meðal íslenskra barna. Laeknabladid. 2017 September: 103 (9): 367-371.

Rognvaldsdottir V, Gudmundsdottir SL, Brychta RJ, Hrafnkelsdottir SM, Gestsdottir S, Arngrimsson SA, Chen KY, Johannsson E. Sleep deficiency on school days in Icelandic youth, as assessed by wrist accelerometry. Sleep Med. 2017 May;33:103-108.

Asgeirsdottir GA, Kjartansdottir I, Olafsdottir AS, Hreinsson JP, Hrafnkelsson H, Johannsson E, Björnsson ES. Helicobacter pylori infection in Icelandic children. Scand J Gastroenterol. 2017 Jun – Jul; 52 (6-7):686-690.

Haukur Heidar Hauksson, Hannes Hrafnkelsson, Kristjan Thor Magnusson, Erlingur Johannsson, Emil L. Sigurdsson. Vitamin D status of Icelandic children and its influence on bone accrual. Journal of Bone and Mineral Metabolism. 2015 Sep;34(5):580-6. 

Indridadottir MH, Sveinsson T, Magnusson KT, Arngrimsson SA, Johannsson E. Prevalence of sport injuries, sport participation and drop out due to injury in young adults. Laeknabladid. 2015 Oktober;101(10):451-456.

Bjarnadottir A, Kristjansdottir AG, Hrafnkelsson H , Johannsson E, Magnusson KT, Thorsdottir I. Insufficient autumn vitamin-D intake and low vitamin-D status in 7-year-old Icelandic children. Public Health Nutrition, Volume 18, Issue 02. February 2015, pp 208 – 212.

Hrafnkelsson H, Magnusson KT, Thorsdottir I, Johannsson E, Sigurdsson EL. Result of school-based intervention on cardiovascular risk factors. Scand J Prim Health Care. 2014 Dec;32(4):149-55.

Hrafnkelsson H, Sigurdsson G, Magnusson Th. K, Sigurdsson L. E, Johannsson E. Fat mass increase in 7-year-old children: More Bone Area but lower Bone Mineral Density. J Bone Miner Metab. 2013 Jul;31(4):442-8.

Magnusson KT, Hrafnkelsson H, Sigurgeirsson I, Johannsson E, Sveinsson T. Limited effects of a 2-year school-based physical activity intervention on body composition and cardiorespiratory fitness in 7-year-old children. Health Educ Res. 2012 Jun; 27(3):484-94.

Magnusson KT, Sigurgeirsson I, Sveinsson T, Johannsson E. Assessment of a two-year school-based physical activity intervention among 7-9-year-old children. Int J Behav Nutr Phys Act. 2011 Dec 20;8(1):138.

Magnusson KT, Arngrimsson SA, Sveinsson T, Johannsson E. Physical activity of 9 and 15 year old Icelandic children – Public health objectives and relations of physical activity to gender, age, anthropometry and area of living. Laeknabladid. 2011 Feb;97(2):75-8.

Kristjánsdóttir AG, Johannsson E, Thorsdottir I. Effects of a school-based intervention on adherence of 7-9-years-olds to food-based dietary guidelines and intake of nutrients. 2010. Public Health Nutrition.2010 Apr 22: 1-11.

Hrafnkelsson Hannes, Sigurdsson Gunnar, Magnusson Th. Kristjan, Johannsson Erlingur, Sigurdsson L. Emil. Predictors of bone mineral density and content in 7-yearold children.  Bone. 2010. Apr: 46(4):1058-62.

Hrafnkelsson H, Magnusson KT, Sigurdsson EL, Johannsson E. Association of BMI and fasting insulin with cardiovascular disease risk factors in seven-year-old Icelandic children. Scand J Prim Health Care. 2009; 27(3):186-91.