| 51. |
- Ludvigsson, Jonas F, et al.
(författare)
-
External review and validation of the Swedish national inpatient register.
- 2011
-
Ingår i: BMC Public Health. - : BioMed Central. - 1471-2458. ; 11, s. 450-
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The Swedish National Inpatient Register (IPR), also called the Hospital Discharge Register, is a principal source of data for numerous research projects. The IPR is part of the National Patient Register. The Swedish IPR was launched in 1964 (psychiatric diagnoses from 1973) but complete coverage did not begin until 1987. Currently, more than 99% of all somatic (including surgery) and psychiatric hospital discharges are registered in the IPR. A previous validation of the IPR by the National Board of Health and Welfare showed that 85-95% of all diagnoses in the IPR are valid. The current paper describes the history, structure, coverage and quality of the Swedish IPR. METHODS AND RESULTS: In January 2010, we searched the medical databases, Medline and HighWire, using the search algorithm "validat* (inpatient or hospital discharge) Sweden". We also contacted 218 members of the Swedish Society of Epidemiology and an additional 201 medical researchers to identify papers that had validated the IPR. In total, 132 papers were reviewed. The positive predictive value (PPV) was found to differ between diagnoses in the IPR, but is generally 85-95%. CONCLUSIONS: In conclusion, the validity of the Swedish IPR is high for many but not all diagnoses. The long follow-up makes the register particularly suitable for large-scale population-based research, but for certain research areas the use of other health registers, such as the Swedish Cancer Register, may be more suitable.
|
|
| 52. |
|
|
| 53. |
- Matthews, Anthony A, et al.
(författare)
-
Benchmarking Observational Analyses Before Using Them to Address Questions Trials Do Not Answer : An Application to Coronary Thrombus Aspiration.
- 2022
-
Ingår i: American Journal of Epidemiology. - : Oxford University Press (OUP). - 0002-9262 .- 1476-6256. ; 191:9, s. 1652-1665
-
Tidskriftsartikel (refereegranskat)abstract
- To increase confidence in the use of observational analyses when addressing effectiveness questions beyond those addressed by randomized trials, one can first benchmark the observational analyses against existing trial results. We used Swedish registry data to emulate a target trial similar to the Thrombus Aspiration in ST-Elevation Myocardial Infarction in Scandinavia (TASTE) randomized trial, which found no difference in the risk of death or myocardial infarction by 1 year with or without thrombus aspiration among individuals with ST-elevation myocardial infarction. We benchmarked the emulation against the trial at 1 year and then extended the emulation's follow-up to 3 years and estimated effects in subpopulations underrepresented in the trial. As in the TASTE trial, the observational analysis found no differences in risk of outcomes by 1 year between groups (risk difference = 0.7 (confidence interval, -0.7, 2.0) and -0.2 (confidence interval, -1.3, 1.0) for death and myocardial infarction, respectively), so benchmarking was considered successful. We additionally showed no difference in risk of death or myocardial infarction by 3 years, or within subpopulations by 1 year. Benchmarking against an index trial before using observational analyses to answer questions beyond those the trial could address allowed us to explore whether the observational data can be trusted to deliver valid estimates of treatment effects.
|
|
| 54. |
- Matthews, Anthony A., et al.
(författare)
-
Comparing Effect Estimates in Randomized Trials and Observational Studies From the Same Population : An Application to Percutaneous Coronary Intervention
- 2021
-
Ingår i: Journal of the American Heart Association. - : John Wiley & Sons. - 2047-9980. ; 10:11, s. 020357-020357
-
Tidskriftsartikel (refereegranskat)abstract
- Background To understand when results from observational studies and randomized trials are comparable, we performed an observational emulation of a target trial designed to ask similar questions as the VALIDATE (Bivalirudin Versus Heparin in ST-Segment and Non-ST-Segment Elevation Myocardial Infarction in Patients on Modern Antiplatelet Therapy) randomized trial. The VALIDATE trial compared the effect of bivalirudin and heparin during percutaneous coronary intervention on the risk of death, myocardial infarction, and bleeding across Sweden. Methods and Results We specified the protocol of a target trial similar to the VALIDATE trial, then emulated the target trial in the period before the VALIDATE trial took place using data from the SWEDEHEART (Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies) registry-the same registry in which the trial was undertaken. The target trial emulation and the VALIDATE trial both estimated little or no effect of bivalirudin versus heparin on the risk of death or myocardial infarction by 180 days (target trial emulation risk ratio for death, 1.21 [95% CI, 0.88 - 1.54]; VALIDATE trial hazard ratio for death, 1.05 [95% CI, 0.78 - 1.41]). The observational data, however, could not capture less severe cases of bleeding, resulting in an inability to define a bleeding outcome like the trial, and could not accurately estimate the comparative risk of death by 14 days, which may be the result of intractable confounding early in follow-up or the inability to precisely emulate the trial's eligibility criteria. Conclusions Using real-world data to emulate a target trial can deliver accurate effect estimates. Yet, even with rich observational data, it is not always possible to estimate the short-term effect of interventions or the effect on outcomes for which data are not routinely collected.
|
|
| 55. |
- Matthews, Anthony, et al.
(författare)
-
Extending treatment effects from a randomized trial using observational data
- 2022
-
Ingår i: Pharmacoepidemiology and Drug Safety. - : John Wiley & Sons. - 1053-8569 .- 1099-1557. ; 31:Suppl. 2, s. 211-211
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Background: To increase confidence in the use of observational data for extending inferences from randomized trials, one can first benchmark. That is, demonstrate the observational analysis can replicate an index trial's findings, before using the observational data to estimate what the trial could not.Objectives: To benchmark an observational study designed to ask the questions to the TASTE trial against results from the TASTE trial itself. Then, if benchmarking is successful, use the observational data to extend the inferences made in the trial.Methods: We use Swedish registry data to emulate a target trial similar to the TASTE randomized trial, which found no difference in the risk of death or myocardial infarction by 1 year with or without thrombus aspiration among individuals with ST-elevation myocardial infarction. We benchmark the emulation against the trial at 1 year, then extend the emulation's follow-up to 3 years and estimate effects in subpopulations underrepresented in the trial.Results: Like TASTE, the observational analysis found no differences in risk of outcomes by 1 year between groups (risk difference 0.7 (0.7, 2.0) and0.2 (1.3, 1.0) for death and myocardial infarction respectively), so benchmarking was considered successful. We additionally show no difference in risk of death or myocardial infarction by 3 years, or within subpopulations by 1 year.Conclusions: Benchmarking before using observational data to extend treatment effects from a randomized trial allows us to understand if the observational data can be trusted to deliver valid estimates of treatment effects.
|
|
| 56. |
- McCarthy, Bridget J, et al.
(författare)
-
Risk factors for oligodendroglial tumors : A pooled international study
- 2011
-
Ingår i: Neuro-Oncology. - Charlottesville, VA : Carden Jennings Pub.. - 1522-8517 .- 1523-5866. ; 13:2, s. 242-250
-
Tidskriftsartikel (refereegranskat)abstract
- Oligodendroglial tumors are rare subtypes of brain tumors and are often combined with other glial tumors in epidemiological analyses. However, different demographic associations and clinical characteristics suggest potentially different risk factors. The purpose of this study was to investigate possible risk factors for oligodendroglial tumors (including oligodendroglioma, anaplastic oligodendroglioma, and mixed glioma). Data from 7 case-control studies (5 US and 2 Scandinavian) were pooled. Unconditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for age group, gender, and study site. Data on 617 cases and 1260 controls were available for analyses. Using data from all 7 studies, history of allergies and/or asthma was associated with a decreased risk of anaplastic oligodendroglioma (OR = 0.6; 95% CI: 0.4-0.9), and history of asthma only was associated with a decreased risk of oligodendroglioma (OR = 0.5; 95% CI: 0.3-0.9) and anaplastic oligodendroglioma (OR = 0.3; 95% CI: 0.1-0.9). A family history of brain tumors was associated with an increased risk of anaplastic oligodendroglioma (OR = 2.2; 95% CI: 1.1-4.5). Having had chicken pox was associated with a decreased risk of oligodendroglioma (OR = 0.6; 95% CI: 0.4-0.9) and anaplastic oligodendroglioma (OR = 0.5; 95% CI: 0.3-0.9) in the US studies. Although there is some overlap in risk factors between oligodendroglial tumors and gliomas as a group, it is likely that additional factors specific to oligodendroglial tumors have yet to be identified. Large, multi-institution international studies will be necessary to better characterize these etiological risk factors.
|
|
| 57. |
- Melin, Beatrice, et al.
(författare)
-
Known glioma risk loci are associated with glioma with a family history of brain tumours : a case-control gene association study
- 2013
-
Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 132:10, s. 2464-2468
-
Tidskriftsartikel (refereegranskat)abstract
- Familial cancer can be used to leverage genetic association studies. Recent genome-wide association studies have reported independent associations between seven single nucleotide polymorphisms (SNPs) and risk of glioma. The aim of this study was to investigate whether glioma cases with a positive family history of brain tumours, defined as having at least one first- or second-degree relative with a history of brain tumour, are associated with known glioma risk loci. One thousand four hundred and thirty-one glioma cases and 2,868 cancer-free controls were identified from four casecontrol studies and two prospective cohorts from USA, Sweden and Denmark and genotyped for seven SNPs previously reported to be associated with glioma risk in casecontrol designed studies. Odds ratios were calculated by unconditional logistic regression. In analyses including glioma cases with a family history of brain tumours (n = 104) and control subjects free of glioma at baseline, three of seven SNPs were associated with glioma risk: rs2736100 (5p15.33, TERT), rs4977756 (9p21.3, CDKN2A-CDKN2B) and rs6010620 (20q13.33, RTEL1). After Bonferroni correction for multiple comparisons, only one marker was statistically significantly associated with glioma risk, rs6010620 (ORtrend for the minor (A) allele, 0.39; 95% CI: 0.250.61; Bonferroni adjusted ptrend, 1.7 x 104). In conclusion, as previously shown for glioma regardless of family history of brain tumours, rs6010620 (RTEL1) was associated with an increased risk of glioma when restricting to cases with family history of brain tumours. These findings require confirmation in further studies with a larger number of glioma cases with a family history of brain tumours.
|
|
| 58. |
- Mogensen, Hanna, et al.
(författare)
-
Educational attainment in survivors of childhood cancer in Denmark, Finland, and Sweden
- 2024
-
Ingår i: British Journal of Cancer. - 0007-0920 .- 1532-1827. ; 130:2, s. 260-268
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Survivors of childhood cancer may face difficulties at school. We investigated whether childhood cancer affects attainment of upper secondary education, in a register-based cohort study from Denmark, Finland, and Sweden, where we limit bias from selection and participation.Methods: From the national cancer registers, we identified all long-term survivors of childhood cancer diagnosed aged 0–14 years in 1971–2005 (n = 7629), compared them to matched population comparisons (n = 35,411) and siblings (n = 6114), using odds ratios (OR) and 95% confidence intervals (CI).Results: Overall, 6127 survivors (80%) had attained upper secondary education by age 25, compared to 84% among comparison groups. Elevated OR for not attaining this level were mainly confined to survivors of central nervous system (CNS) tumours (ORSurv_PopComp2.05, 95%CI: 1.83–2.29). Other risk groups were survivors who had spent more time in hospital around cancer diagnosis and those who had hospital contacts in early adulthood, particularly psychiatric. Survivors of all cancer types were less likely to have attained upper secondary education without delay.Conclusions: Although survivors of childhood cancer experienced delays in their education, many had caught up by age 25. Except for survivors of CNS tumours, survivors attained upper secondary education to almost the same extent as their peers.
|
|
| 59. |
- Mogensen, Hanna, et al.
(författare)
-
Number of siblings and survival from childhood leukaemia : a national register-based cohort study from Sweden
- 2021
-
Ingår i: British Journal of Cancer. - Stockholm : Karolinska Institutet, Institute of Environmental Medicine. - 0007-0920 .- 1532-1827.
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Previous studies suggest worse leukaemia survival for children with siblings, but the evidence is sparse, inconsistent and does not consider clinical factors. We explored the associations between number of siblings in the household, birth order, and survival from childhood acute lymphoid leukaemia (ALL) and acute myeloid leukaemia (AML). Methods: In this nationwide register-based study we included all children aged 1-14, diagnosed with ALL and AML between 1991-mid 2015 in Sweden (n=1692). Using Cox regression models, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs) according to number of siblings and birth order, adjusting for known prognostic and sociodemographic factors. Results: A tendency towards better ALL survival among children with one, or ≥2, siblings was observed, adjHRs (95% CI): 0.73 (0.49-1.10) and 0.63 (0.40-1.00), respectively. However, this was mainly limited to children with low risk profiles. An indication of better AML survival among children with siblings was seen, adjHRs (95% CI) 0.68 (0.36-1.29) and 0.71 (0.34-1.48) but diminished after adjusting for birth order. Conclusion: Our results do not support previous findings that a larger number of siblings is associated with poorer survival. Inconsistencies might be explained by underlying mechanisms that differ between settings, but chance cannot be ruled out.
|
|
| 60. |
|
|
