| New articles - Uudet artikkelit
22.1.2007 - ISI Web of Knowledge & PubMed Search Alert |
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The epidemiology of alexithymia Aino, M., Jouko, S. and Matti, J. Journal of Psychosomatic Research. 2006; 61(3): 390-391. Meeting Abstract. IF 2.052 Badeau, R., Jauhiainen, M., Metso, J., Nikander, E., Tikkanen, M. J., Ylikorkala, O. and Mikkola, T. S. Menopause. 2007. Journal article. IF 3.913 OBJECTIVE: Isoflavones may display beneficial health effects in
postmenopausal women. We studied in a clinical trial whether
isolated isoflavone treatment in postmenopausal women could affect
reverse cholesterol transport as evaluated by adenosine
triphosphate-binding cassette A1- (ABCA1), dependent cholesterol
efflux from macrophages. In addition, various serum lipid and
lipoprotein parameters were investigated. Furthermore, we
separately assessed equol-producing and non-equol-producing
women. Dowdle, W., Van der Avoort, H., de Gourville, E., Delpeyroux, F., Desphande, J., Hovi, T., Martin, J., Pallansch, M., Kew, O. and Wolff, C. Risk Analysis. 2006; 26(6): 1449-1469. Review. IF 1.510 The goal of the World Health Organization is to stop routine use of oral poliovirus vaccine shortly after interruption of wild poliovirus transmission. A key component of this goal is to minimize the risk of reintroduction by destruction of polioviruses except in an absolute minimum number of facilities that serve essential functions and implement effective containment. Effective containment begins with a complete facility risk assessment. This article focuses on characterizing the risks of exposure to polioviruses from the essential vaccine production, quality control, and international reference and research facilities that remain. We consider the potential exposure pathways that might lead to a poliovirus reintroduction, including para-occupational exposures and releases to the environment, and review the literature to provide available estimates and a qualitative assessment of containment risks. Minimizing the risk of poliovirus transmission from a poliovirus facility to increasingly susceptible communities is a crucial and ongoing effort requiring understanding and actively managing the potential exposure pathways. Genetic impairment of frontocortical endocannabinoid degradation and high alcohol preference Hansson, A. C., Bermudez-Silvaz, F. J., Hyytia, P., Sanchez-Vera, I., Rimondini, R., de Fonseca, F. R., Kunos, G., Sommer, W. H. and Heilig, M. Neuropsychopharmacology. 2007; 32(1): 117-126. Article. IF 5.369 Endocannabinoid signaling has recently been implicated in ethanol-seeking behavior. We analyzed the expression of endocannabinoid-related genes in key brain regions of reward and dependence, and compared them between the alcohol-preferring AA (Alko Alcohol) and nonpreferring ANA (Alko Non-Alcohol) rat lines. A decreased expression of fatty acid amidohydrolase (FAAH), the main endocannabinoid-degrading enzyme, was found in prefrontal cortex (PFC) of AA rats, and was accompanied by decreased enzyme activity in this region. Binding of the endocannabinoid-cannabinoid 1 (CB1) receptor ligand (3)[H]SR141716A, and [35S]GTP gamma S incorporation stimulated by the CB1 agonist WIN 55,2 12-2 were downregulated in the same area. Together, this suggests an overactive endocannabinoid transmission in the PFC of AA animals, and a compensatory downregulation of CB1 signaling. The functional role of impaired FAAH function for alcohol self-administration was validated in two independent ways. The CB1 antagonist SR141716A potently and dose-dependently suppressed self-administration in AA rats when given systemically, or locally into the PFC, but not in the striatum. Conversely, intra-PFC injections of the competitive FAAH inhibitor URB597 increased ethanol self-administration in nonselected Wistar rats. These results show for the first time that impaired FAAH function may confer a phenotype of high voluntary alcohol intake, and point to a FAAH both as a potential susceptibility factor and a therapeutic target. Official marital status, cohabiting, and self-rated health-time trends in Finland, 1978-2001 Joutsenniemi, K. E., Martelin, T. P., Koskinen, S. V., Martikainen, P. T., Harkanen, T. T., Luoto, R. M. and Aromaa, A. J. Eur J Public Health. 2006; 16(5): 476-83. Journal Article Research Support, Non-U.S. Gov't. IF BACKGROUND: Married persons are healthier and live longer than single, divorced, and widowed persons. Time trends in self-rated health (SRH) by marital status and cohabitation have remained largely unstudied. We aim to assess the levels and trends of SRH by official marital status and cohabitation, and to study the causes of these differences. METHODS: Two nationally representative cross-sectional surveys were conducted 20 years apart in Finland. Data on self-reported marital status, SRH, education, smoking, and long-standing illness were collected from Finns aged 30-64 years in 1978-80 (Mini-Finland Health Survey, N = 6102, response rate 96%) and 2000-01 (Health 2000 Survey, N = 5871, response rate 92%). RESULTS: SRH has improved in the last 20 years, but differences between marital status groups have not reduced. In 2000-01, non-married persons reported worse SRH than married persons. Among men, single [cumulative odds ratio (COR) = 1.55; 95% confidence interval (95% CI) 1.22-1.99] and divorced (COR = 1.55; 95% CI 1.17-2.05) persons showed the poorest SRH, while among women widows (1.53; 95% CI 1.04-2.26) were the most disadvantaged group. The SRH of cohabiting persons did not significantly differ from that of married persons. Differences in educational structure, smoking, and the prevalence of long-term illness explain part of the marital status differences in SRH among men, but less so among women. Among both single men and women as well as among widowed women, SRH had improved slightly less than in the other groups. CONCLUSION: The challenges on public health posed by growing numbers of currently not married people are likely to increase. Kaunisto, M. A., Kallela, M., Hamalainen, E., Kilpikari, R., Havanka, H., Harno, H., Nissila, M., Sako, E., Ilmavirta, M., Liukkonen, J., Teirmaa, H., Tornwall, O., Jussila, M., Terwilliger, J., Farkkila, M., Kaprio, J., Palotie, A. and Wessman, M. Cephalalgia. 2006; 26(12): 1462-1472. Article. IF 4.657 Among the few independently replicated genetic associations in migraine are polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) and oestrogen receptor (ESR1) genes. We studied the contribution of these genes to migraine susceptibility by genotyping six MTHFR and 26 ESR1 polymorphisms in 898 unrelated migraine with aura (MA) patients and in 900 unrelated healthy controls. There were no differences in the genotype distributions of the previously migraine-associated SNPs C677T (MTHFR) and G2014A (ESR1) between cases and controls (P-values 0.83 and 0.55, respectively). Thus, we were not able to replicate the previous findings, although our study had considerable power. However, five of the ESR1 SNPs (rs6557170, rs2347867, rs6557171, rs4870062 and rs1801132) that were in strong linkage disequilibrium were nominally associated with MA (uncorrected P-values 0.007-0.034). These results did not, however, remain significant after taking multiple testing into account. Thus it seems unlikely that the studied genes are involved in migraine susceptibility, at least in this sample. Lehto, M., Kotovuori, A., Palosuo, K., Varjonen, E., Lehtimaki, S., Kalkkinen, N., Palosuo, T., Reunala, T. and Alenius, H. Clinical and Experimental Allergy. 2007; 37(1): 133-140. Article. IF 3.553 Hev b 6.01 (prohevein) and Hev b 5 [acidic natural rubber latex (NRL) protein] are major IgE-binding allergens in NRL allergy. To examine allergen-specific cytokine and chemokine responses in NRL-allergic patients. Fourteen NRL-allergic patients and 10 healthy controls participated in the study. Hev b 6.01 and Hev b 5 were purified under non-denaturating conditions by chromatographic methods. Specific IgE antibodies were measured by ELISA and proliferation of peripheral blood mononuclear cells (PBMC) by H-3-thymidine incorporation assay. Allergen-specific induction of cytokine and chemokine mRNA in PBMC was measured by real-time PCR and protein levels by ELISA. Surface expression of chemokine receptors was analysed by flow cytometry. Twelve (86%) NRL-allergic patients had positive skin prick test reactions and IgE antibodies against Hev b 6.01, but less than 30% responded to Hev b 5. Cell proliferation against Hev b 6.01, but not against Hev b 5, was significantly increased. Both allergens elicited significantly higher expression of pro-inflammatory and T-helper type 2 cytokines (TNF, IL-12p40, IL-13) and chemokines (CCL3, CCL4, CCL20) in the NRL-allergic patients than in controls. Interestingly, mRNA expression of the regulatory cytokine TGF-beta 1 was reduced, whereas IL-10 expression was enhanced after allergen stimulations in patients with NRL allergy. Finally, the NRL-allergic patients showed increased CCR4 expression on CD3(+)CD8(-) T cells and decreased CXCR3 expression on CD3(+)CD8(+) T cells. Allergen-specific induction of cytokines and chemokines in PBMC and chemokine receptor expression on circulating T cells may contribute to the pathogenesis of NRL allergy. Lehtola, M. J., Miettinen, I. T., Hirvonen, A., Vartiainen, T. and Martikainen, P. J. Int J Hyg Environ Health. 2007. Journal article. IF 1.421 The numbers of bacteria generally increase in distributed water. Often household pipelines or water fittings (e.g., taps) represent the most critical location for microbial growth in water distribution systems. According to the European Union drinking water directive, there should not be abnormal changes in the colony counts in water. We used a pilot distribution system to study the effects of water stagnation on drinking water microbial quality, concentration of copper and formation of biofilms with two commonly used pipeline materials in households; copper and plastic (polyethylene). Water stagnation for more than 4h significantly increased both the copper concentration and the number of bacteria in water. Heterotrophic plate counts were six times higher in PE pipes and ten times higher in copper pipes after 16h of stagnation than after only 40min stagnation. The increase in the heterotrophic plate counts was linear with time in both copper and plastic pipelines. In the distribution system, bacteria originated mainly from biofilms, because in laboratory tests with water, there was only minor growth of bacteria after 16h stagnation. Our study indicates that water stagnation in the distribution system clearly affects microbial numbers and the concentration of copper in water, and should be considered when planning the sampling strategy for drinking water quality control in distribution systems. Surveillance, laboratory diagnosis and research of communicable diseases in EU Leinikki, P. Journal of Clinical Virology. 2006; 36: S3-S3. Meeting Abstract. IF 2.623 Madeleine, M. M., Anttila, T., Schwartz, S. M., Saikku, P., Leinonen, M., Carter, J. J., Wurscher, M., Johnson, L. G., Galloway, D. A. and Daling, J. R. International Journal of Cancer. 2007; 120(3): 650-655. Article. IF 4.700 Human papillomavirus (HPV) is the central etiologic factor for cervical cancer, and prior studies suggested C. trachomatis may act as an HPV cofactor. We examined the C. trachomatis-cervical cancer association by serotype, histology, HPV type in the tumor, an other HPV cofactors. We conducted a population-based study in the Seattle-Puget Sound area of 302 women with invasive squamous cell carcinomas (SCC), 185 women with adenocarcinomas of the cervix (AC), and 318 HPV seropositive control women. The risk of SICC associated with antibodies to C. trachomatis was increased (OR 1.6, 95 % CI 1.1-2.2) but not for AC (OR 1.0, 95 % C1 0.6-1.5). This association was independent of HPV type in the SCC tumor tissue. There was an association between specific serotypes of C. trachomatis and SCC for 6 of the 10 serotypes: B (OR 3.6, 95 % CI 1.5-8.4), D (OR 2.1, 95 % CI 1.2-3.5), E (OR 2.4, 95 % CI, 1.4-3.9), G (OR 3.0, 95 % CI, 1.1-7.9), 1 (OR 4.2, 95 % CI, 1.5-11.7), and J (OR 2.3, 95% CI 1.0-5.1), but not for the 4 types (C, F, H, and K) that were present at very low prevalence in this population. There was an increased risk of SCC, but not AC, associated with antibodies to C. trachomatis that was not serotype specific. (c) 2006 Wiley-Liss, Inc. Bioportfolio: lifelong tissue persistence of new and old parvoviruses Norja, R., Hokynar, K., Aaltonen, L. M., Chen, R., Ranki, A., Partio, E., Kiviluoto, O., Davidkin, I., Leivo, T., Eis-Hubinger, A. M., Schneider, B., Fischer, H. R., Tolba, R., Vapalahti, O., Vaheri, A., Soderlund-Venermo, M. and Hedman, K. Journal of Clinical Virology. 2006; 36: S8-S8. Meeting Abstract. IF 2.623 When intracellular logistics fails - genetic defects in membrane trafficking Olkkonen, V. M. and Ikonen, E. Journal of Cell Science. 2006; 119(24): 5031-5045. Editorial Material. IF 6.543 The number of human genetic disorders shown to be due to defects in membrane trafficking has greatly increased during the past five years. Defects have been identified in components involved in sorting of cargo into transport carriers, vesicle budding and scission, movement of vesicles along cytoskeletal tracks, as well as in vesicle tethering, docking and fusion at the target membrane. The nervous system is extremely sensitive to such disturbances of the membrane trafficking machinery, and the majority of these disorders display neurological defects - particularly diseases affecting the motility of transport carriers along cytoskeletal tracks. In several disorders, defects in a component that represents a fundamental part of the trafficking machinery fail to cause global transport defects but result in symptoms limited to specific cell types and transport events; this apparently reflects the redundancy of the transport apparatus. In groups of closely related diseases such as Hermansky-Pudlak and Griscelli syndromes, identification of the underlying gene defects has revealed groups of genes in which mutations lead to similar phenotypic consequences. New functionally linked trafficking components and regulatory mechanisms have thus been discovered. Studies of the gene defects in trafficking disorders therefore not only open avenues for new therapeutic approaches but also significantly contribute to our knowledge of the fundamental mechanisms of intracellular membrane transport. Infant Growth and Stroke in Adult Life. The Helsinki Birth Cohort Study Osmond, C., Kajantie, E., Forsen, T. J., Eriksson, J. G. and Barker, D. J. Stroke. 2007. Journal article. IF 5.855 BACKGROUND AND PURPOSE: People who had low birth weight are at increased risk of stroke. Little is known about the effects of early postnatal growth on stroke risk. METHODS: We followed-up 12 439 people born in Helsinki during 1934 to 1944. Their body size was measured at birth and, on average, 9 times between birth and age 2 years; 507 of them were hospitalized with stroke or died from the disease. RESULTS: Hazard ratios for stroke declined progressively with increasing gain in weight between birth and age 2 years. The hazard ratio was 0.85 (95% CI, 0.78 to 0.93; P=0.0004) per standard deviation increase in the difference between the weight attained at age 2 years and that predicted from birth weight. A 1-standard deviation increase in body mass index at 2 years of age was associated with a hazard ratio for stroke of 0.84 (95% CI, 0.77 to 0.92; P=0.0002). This association was little changed by adjustment for measures of socio-economic status. Change in body size after the age of 2 years had little effect on the risk of later stroke. People whose mothers had a small external conjugate diameter of the pelvis had an increased risk of stroke. The hazard ratio associated with a diameter of </=18 cm was 1.62 (95% CI, 1.30 to 2.02; P<0.0001). CONCLUSIONS: Thinness during infancy is associated with an increased risk of stroke in later life. This association may be the result of maternal influences which originated in the mother's infancy when her pelvic shape was established. Sinclair, D. Biochemical Genetics. 2006; 44(7-8): 385-390. Article. IF 0.776 Luo [Biochem. Genet. 43:223-227] concluded, "The mutation ALDH2* 487Lys allele is not deleterious but is of great benefit to human health." This statement is easily subject to misinterpretation and needs to be clarified. Their results actually show there is a pleiotropic effect associated with the mutation ALDH2* 487Lys allele that is as deleterious as the risk of alcoholism for which it offers protection, and thus there is no net benefit from having the mutation. A clarification is needed because this statement and others in the paper might be used inappropriately as an endorsement of practices that are in fact worthless, because it masks the need to find what the pleiotropic effect is, and because it seems to contradict what otherwise seems to be a general rule of evolution. Siren, J., Imaizumi, T., Sarkar, D., Pietila, T., Noah, D. L., Lin, R., Hiscott, J., Krug, R. M., Fisher, P. B., Julkunen, I. and Matikainen, S. Microbes Infect. 2006; 8(8): 2013-20. Journal Article. IF 3.154 Research Support, N.I.H., Extramural. Research Support, Non-U.S. Gov't. Activation of host cell antiviral responses is mediated by pattern recognition receptors. Cytoplasmic RNA helicases, retinoic acid inducible gene-I (RIG-I) and melanoma differentiation-associated gene 5 (mda-5) have been identified to function as receptors for double-stranded RNA. Here we show that interferon (IFN)-alpha pretreatment enhances influenza A virus-induced expression of IFN-alpha, IFN-beta, interleukin (IL)-28 and IL-29 genes in human dendritic cells and epithelial cell lines. Both IFN-alpha and IFN-beta strongly enhanced RIG-I and mda-5 mRNA and protein expression in these cell types. Expression of RIG-I and mda-5 gene constructs, but not that of TLR3, lead to a dramatic enhancement of IFN-beta promoter driven transcription in influenza A virus-infected epithelial cells. Furthermore, dominant negative RIG-I gene construct inhibited influenza A virus-induced IFN-beta promoter activity. In conclusion, our results show that in epithelial cells influenza A virus-induced antiviral cytokine gene expression is triggered by RIG-I and mda-5, whose expression is positively regulated by IFN-alpha. Sokero, P., Eerola, M., Rytsala, H., Melartin, T., Leskela, U., Lestela-Mielonen, P. and Isometsa, E. J Affect Disord. 2006; 95(1-3): 95-102. Journal Article. IF 3.078 BACKGROUND: Suicidal ideation is likely to represent a phase preceding suicidal acts among most suicidal patients with major depressive disorder (MDD). Factors predicting reversal of the suicidal process are unknown. Our aim was to test the hypothesis that a decline in suicidal ideation is preceded by a decline in hopelessness among patients with MDD. METHOD: Of the 269 Vantaa Depression Study patients with DSM-IV MDD, 103 patients scored > or = 6 points at baseline on the Scale for Suicidal Ideation (SSI). Seventy of these patients were followed-up weekly either until they scored zero points on the SSI, or up to 26 weeks. RESULTS: The median duration for a decline of suicidal ideation to zero was 2.2 months after baseline. The level of baseline suicidal ideation, depressive symptoms, and the presence of any personality disorder predicted duration of suicidal ideation. A decline in both depression (BDI) and hopelessness (HS) independently predicted a decline in suicidal ideation. LIMITATIONS: Due to study design, we do not know if suicidal ideation relapsed after the first time the patient reached zero score in the SSI. CONCLUSIONS: Among patients with major depressive disorder having suicidal ideation, the decline in suicidal ideation is independently predicted by preceding declines in the levels of both depressive symptoms as well as hopelessness. The findings are consistent with possible causal roles of declines in depression and hopelessness in reversing the suicidal process. Strengell, M., Lehtonen, A., Matikainen, S. and Julkunen, I. Journal of Leukocyte Biology. 2006; 79(6): 1279-1285. Article. IF 4.627 Dendritic cells (DCs) play an important role in innate and adaptive immune responses. In addition to their phagocytic activity, DCs present foreign antigens to naive T cells and regulate the development of adaptive immune responses. Upon contact with DCs, activated T cells produce large quantities of cytokines such as interferon-gamma (IFN-gamma) and interleukin (IL)-21, which have important immunoregulatory functions. Here, we have analyzed the effect of IL-21 and IFN-gamma on lipopolysaccharide (LPS)-induced maturation and cytokine production of human monocyte-derived DCs. IL-21 and IFN-gamma receptor genes were expressed in high levels in immature DCs. Pretreatment of immature DCs with IL-21 inhibited LPS-stiniulated DC maturation and expression of CD86 and human leukocyte antigen class II (HLAII). IL-21 pretreatment also dramatically reduced LPS-stimulated production of tumor necrosis factor alpha, IL-12, CC chemokine ligand 5 (CCL5), and CXC chemokine ligand 10 (CXCL10) but not that of CXCL8. In contrast, IFN-gamma had a positive feedback effect on immature DCs, and it enhanced LPS-induced DC maturation and the production of cytokines. IL-21 weakly induced the expression Toll-like receptor 4 (TLR4) and translation initiation region (TIR) domain-containing adaptor protein (TIRAP) genes, whereas the expression of TIR domain-containing adaptor-inducing IFN-beta (TRIF), myeloid differentiation (MyD88) 88 factor, or TRIF-related adaptor molecule (TRAM) genes remained unchanged. However, IL-21 strongly stimulated the expression-of suppressor of cytokine signaling (SOCS)-1 and SOCS-3 genes. SOCS are known to suppress DC functions and interfere with TLR4 signaling. Our results demonstrate that IL-21, a cytokine produced by activated T cells, can directly inhibit the activation and cytokine production of myeloid DCs, providing a negative feedback loop between DCs and T lymphocytes. Determinants of psychiatric hospitalization after attempted suicide Suominen, K. and Lonnqvist, J. Gen Hosp Psychiatry. 2006; 28(5): 424-30. Journal Article. IF 2.248 OBJECTIVE: This study investigated the characteristics of suicide attempters referred to psychiatric hospitals and the factors affecting such referral. METHOD: All 1198 consecutive suicide attempters treated in general hospital emergency rooms in Helsinki during a 12-month period were identified. Data on all health care contacts 1 year before the index attempt and on referrals to psychiatric hospitals after the attempt were gathered. RESULTS: We found that a quarter of patients were referred to psychiatric hospitals as inpatients after index suicide attempts. Factors predicting referral to psychiatric hospitals, compared to nonreferral, were older age, psychotic disorder, mood disorder, lack of alcohol consumption preceding the attempt, somatic illness, suicide attempt on a weekday, previous psychiatric treatment, psychiatric consultation and the hospital treating the suicide attempt. CONCLUSION: Although the clinical characteristics of patients attempting suicide are a major determinant of whether they are subsequently referred to psychiatric hospitals, the treatment practices of emergency room hospitals also influence treatment decisions. Tiittanen, M., Huupponen, J. T., Knip, M. and Vaarala, O. Diabetes. 2006; 55(12): 3446-54. Journal Article Research Support, Non-U.S. Gov't. IF 8.082 Patients with type 1 diabetes are treated with daily injections of human insulin, an autoantigen expressed in thymus. Natural CD4(+)CD25(high) regulatory T-cells are derived from thymus, and accordingly human insulin-specific regulatory T-cells should exist. We had a chance to study peripheral blood mononuclear cells (PBMCs) from children with type 1 diabetes both before and after starting insulin treatment, and thus we could analyze the effects of insulin treatment on regulatory T-cells in children with type 1 diabetes. PBMCs were stimulated for 72 h with bovine/human insulin. The mRNA expression of regulatory T-cell markers (transforming growth factor-beta, Foxp3, cytotoxic T-lymphocyte antigen-4 [CTLA-4], and inducible co-stimulator [ICOS]) or cytokines (gamma-interferon [IFN-gamma], interleukin [IL]-5, IL-4) was measured by quantitative RT-PCR. The secretion of IFN-gamma, IL-2, IL-4, IL-5, and IL-10 was also studied. The expression of Foxp3, CTLA-4, and ICOS mRNAs in PBMCs stimulated with bovine or human insulin was higher in patients on insulin treatment than in patients studied before starting insulin treatment. The insulin-induced Foxp3 protein expression in CD4(+)CD25(high) cells was detectable in flow cytometry. No differences were seen in cytokine activation between the patient groups. Insulin stimulation in vitro induced increased expression of regulatory T-cell markers, Foxp3, CTLA-4, and ICOS only in patients treated with insulin, suggesting that treatment with human insulin activates insulin-specific regulatory T-cells in children with newly diagnosed type 1 diabetes. This effect of the exogenous autoantigen could explain the difficulties to detect in vitro T-cell proliferation responses to insulin in newly diagnosed patients. Furthermore, autoantigen treatment-induced activation of regulatory T-cells may contribute to the clinical remission of the disease. Tolonen, H., Helakorpi, S., Talala, K., Helasoja, V., Martelin, T. and Prattala, R. Eur J Epidemiol. 2006; 21(6): 409-15. Journal Article. IF 1.361 When estimating population level changes in health indicators, the declining response rate, especially if also the characteristics of non-respondents are changing may bias the outcome. There is evidence that survey response rates are declining in many countries. It is also known that respondents and non-respondents differ in their socio-economic and demographic status as well as in their health and health behaviours. There is no information about the changes in the differences between respondents and non-respondents over time. Our purpose was to investigate the changes over time in the differences between respondents and non-respondents in respect to their sex, age, marital status and educational level. The data from the Finnish Adult Health Behaviour Survey (1978-2002) was used. The response rate declined over the past 25 years for both men and women in all age groups. The decline was faster among men than women, and also faster in younger age groups than older age groups. There is a marked difference in the response rate between married and non-married persons but it did not change over time. Also the response rate between different educational levels differed for both men and women, and this difference increased over the years. The declining response rate and at the same time occurring change in the non-respondent characteristics will decrease the representativeness of the results, limit the comparability of the results with other surveys, increase the bias of the trend estimates and limit the comparability of the results between population groups. |