Background:Population-based health registers are potential assets in epidemiological research; however, the quality of case ascertainment is crucial.Objective:To compare the case ascertainment of dementia, from the National Patient Register (NPR) and the Cause of Death Register (CDR) with dementia diagnoses from six Swedish population based studies.Methods:Sensitivity, specificity, and positive predictive value (PPV) of dementia identification in NPR and CDR were estimated by individual record linkage with six Swedish population based studies (n = 19,035). Time to detection in NPR was estimated using data on dementia incidence from longitudinal studies with more than two decades of follow-up.Results:Barely half of the dementia cases were ever detected by NPR or CDR. Using data from longitudinal studies we estimated that a record with a dementia diagnosis appears in the NPR on average 5.5 years after first diagnosis. Although the ability of the registers to detect dementia cases was moderate, the ability to detect non-dementia cases was almost perfect (99%). When registers indicate that there is a dementia diagnosis, there are very few instances in which the clinicians determined the person was not demented. Indeed, PPVs were close to 90%. However, misclassification between dementia subtype diagnoses is quite common, especially in NPR.Conclusions:Although the overall sensitivity is low, the specificity and the positive predictive value are very high. This suggests that hospital and death registers can be used to identify dementia cases in the community, but at the cost of missing a large proportion of the cases.

Background: Swedish population-based national health registers are widely used data sources in epidemiological research. Register-based diagnoses of Parkinson’s disease have not been validated against clinical information. Methods: Parkinson’s disease (PD) and other parkinsonian disorder diagnoses were ascertained in two registers, i.e. the National Patient Register (NPR) and the Cause of Death Register (CDR). Diagnoses were validated in terms of accuracy (positive predictive value) and sensitivity against data from a population-based study of PD in 1998–2004 that screened more than 35,000 persons and identified 194 cases of parkinsonian disorders including 132 PD cases (the gold standard for the purposes of this study). Results: Accuracy for any parkinsonian disorder diagnoses was 88.0% in the NPR and 94.4% in the CDR. Accuracy of PD diagnoses was 70.8% in the NPR and 66.7% in the CDR. Misclassification between differential parkinsonian diagnoses was common. The accuracy of PD diagnoses in the NPR improved to 83.0% by restricting the definition to primary diagnoses only. The sensitivity of PD diagnoses in the NPR and CDR combined was 83.1%, with a mean time to detection of 6.9 years. Conclusions: Population-based national health registers are valid data sources in epidemiological studies of PD or parkinsonian disorder etiology but are less suitable in studies of incidence or prevalence.

PURPOSE To examine the association between primary care practitioner (physician and nurse) empathy and incidence of cardiovascular disease (CVD) events and all-cause mortality among patients with type 2 diabetes. METHODS This was a population-based prospective cohort study of 49 general practices in East Anglia (United Kingdom). The study population included 867 individuals with screen-detected type 2 diabetes who were followed up for an average of 10 years until December 31, 2014 in the Anglo-Danish-Dutch Study of Intensive Treatment in People With Screen Detected Diabetes in Primary Care (ADDITION)-Cambridge trial. Twelve months after diagnosis, patients assessed practitioner empathy and their experiences of diabetes care during the preceding year using the consultation and relational empathy (CARE) measure questionnaire. CARE scores were grouped into tertiles. The main outcome measures were first recorded CVD event (a composite of myocardial infarction, revascularization, nontraumatic amputation, stroke, and fatal CVD event) and all-cause mortality, obtained from electronic searches of the general practitioner record, national registries, and hospital records. Hazard ratios (HRs) were estimated using Cox models adjusted for relevant confounders. The ADDITION-Cambridge trial is registered as ISRCTN86769081. RESULTS Of the 628 participants with a completed CARE score, 120 (19%) experienced a CVD event, and 132 (21%) died during follow up. In the multivariable model, compared with the lowest tertile, higher empathy scores were associated with a lower risk of CVD events (although this did not achieve statistical significance) and a lower risk of all-cause mortality (HRs for the middle and highest tertiles, respectively: 0.49; 95% CI, 0.27-0.88, P = .01 and 0.60; 95% CI, 0.35-1.04, P = .05). CONCLUSIONS Positive patient experiences of practitioner empathy in the year after diagnosis of type 2 diabetes may be associated with beneficial long-term clinical outcomes. Further work is needed to understand which aspects of patient perceptions of empathy might influence health outcomes and how to incorporate this understanding into the education and training of practitioners.

BackgroundConcerns have been raised that HPV-vaccination might affect women’s cervical screening behavior. We therefore investigated the association between opportunistic HPV-vaccination and attendance after invitation to cervical screening.MethodsA cohort of all women resident in Sweden, born 1977-1987 (N=629,703), and invited to cervical screening, was followed October 2006 - December 2012. Invitations to screening were identified via the National Quality Register for Cervical Cancer Prevention, as was the primary outcome of a registered smear. Vaccination status was obtained from two nationwide health data registers. Hazard ratios (HR) were estimated using Cox regression adjusted for age, education level and income (HRadj). Women were individually followed for up to 6 years, of which the first and second screening rounds were analyzed separately.ResultsScreening attendance after three years of follow-up was 86% in vaccinated women (N=4,897) and 75% in unvaccinated women (N=625,804). The crude HR of screening attendance in vaccinated vs. unvaccinated women was 1.31 (95% CI 1.27-1.35) in the first screening round. Adjustment for education and income reduced but did not erase this difference (HRadj=1.09, 95% CI 1.05-1.13). In the second screening round, attendance was likewise higher in HPV-vaccinated women (crude HR=1.26, 95% CI 1.21-1.32; HRadj=1.15, 95% CI 1.10-1.20).ConclusionsHPV-vaccination is so far associated with equal or higher attendance to cervical screening in Sweden in a cohort of opportunistically vaccinated young women. Most but not all of the difference in attendance was explained by socioeconomic differences between vaccinated and unvaccinated women. HPV vaccine effectiveness studies should consider screening attendance of HPV-vaccinated women when assessing incidence of screen-detected cervical lesions.