Dataset Information

Validation of multiple sclerosis diagnoses in the Swedish National Patient Register.

ABSTRACT: Population-based registers are widely used in epidemiological studies. We aimed to estimate the validity of multiple sclerosis (MS) diagnoses registered in the Swedish National Patient Register (NPR) by two sequential register-based case-definition algorithms. Prevalent MS patients aged 16-64 years were identified from the in- and specialised out-patient NPR in 2001-2013, using International Classification of Diseases code G35. These identified MS diagnoses were validated through two sequential register-based case-definition algorithms, as the 'gold-standard' reference, by linking individual-level data longitudinally to other nationwide registers. The primary algorithm first sought to corroborate the MS diagnoses with MS-specific information in other nationwide registers. The exploratory secondary algorithm identified individuals with MS-related information in other registers and those who were unable to be followed sufficiently. Through multi-register linkage, we estimated the number of confirmed and uncertain individuals with an MS diagnosis recorded in the NPR. A total of 19,781 individuals (mean age at first visit 45.2 years; 69.5% women) had at least one MS diagnosis recorded in the NPR during 2001-2013. Using the two case-definition algorithms, 92.5% (n?=?18,291) of the MS diagnoses recorded in the NPR were confirmed, while 7.5% (n?=?1490) remained uncertain. Our findings indicate that a very high percentage of patients coded with an MS diagnosis in the Swedish NPR actually have MS, and supports the use of the NPR as a viable source to identify individuals with an MS diagnosis for population-based research. This exploratory methods paper suggests an alternative novel method to verify individuals' diagnoses in register-based settings.

SUBMITTER: Murley C

PROVIDER: S-EPMC7010617 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Validation of multiple sclerosis diagnoses in the Swedish National Patient Register.

Murley Chantelle C Friberg Emilie E Hillert Jan J Alexanderson Kristina K Yang Fei F

European journal of epidemiology 20190906 12

Population-based registers are widely used in epidemiological studies. We aimed to estimate the validity of multiple sclerosis (MS) diagnoses registered in the Swedish National Patient Register (NPR) by two sequential register-based case-definition algorithms. Prevalent MS patients aged 16-64 years were identified from the in- and specialised out-patient NPR in 2001-2013, using International Classification of Diseases code G35. These identified MS diagnoses were validated through two sequential ...[more]

PMID: 31493189

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Project description:Background and aimsIdentification of child abuse involves a medical investigation and assessment of problems related to social environment and upbringing and might necessitate out-of-home care. The objective of this study was to analyse infants placed in out-of-home care in Sweden by incidence, medical diagnoses, and perinatal factors.MethodsThis was a population-based register study of infants born in Sweden 1997 to 2014. Data were retrieved from registers at the Swedish National Board of Health and Welfare and Statistics Sweden. Outcome measures were out-of-home care categories: (a) "Problems Related to Social Environment/Upbringing", (b) "Abuse diagnoses without SDH (subdural haemorrhage), RH (retinal haemorrhage), rib fracture, or long bone fracture", and (c) "SDH, RH, rib fracture, or long bone fracture." As a reference population, we randomly selected infants without medical diagnoses born the same year.ResultsOverall incidence of out-of-home care was 402 per 100 000. For subcategories (a), (b), and (c), the incidences were 14.8 (n = 273), 3.77 (n = 70), and 9.83 (n = 182) per 100 000, respectively. During the study period, the first remained unchanged; the latter two have been increasing. Compared with other reasons for out-of-home care, children in category (c), "SDH, RH, rib fracture, or long bone fracture", had increased odds of being boys (adjusted odds ratio [aOR] 1.60; 95% confidence interval [CI], 1.08-2.38) and decreased odds of having a mother being single (aOR 0.49; 95% CI, 0.32-0.75) and a smoker (aOR 0.60; 95% CI, 0.37-0.96). Compared with the reference population, children in this category were more often twin born (7.7% versus 2.8%), preterm (18.5% versus 5.5%), and small-for-gestational age (5.2% versus 2.1%).ConclusionSDH, RH, rib fracture, or long bone fracture constitute a minor part of medical diagnoses for infants entered in out-of-home care, but have been increasing, both in numbers and proportion. Overdiagnosis of abuse might be a possible reason but cannot be ascertained by this study design.

Project description:ObjectivesIn the International Classification of Diseases, Tenth Edition (ICD-10), hypochondriasis (illness anxiety disorder) and dysmorphophobia (body dysmorphic disorder) share the same diagnostic code (F45.2). However, the Swedish ICD-10 allows for these disorders to be coded separately (F45.2 and F45.2A, respectively), potentially offering unique opportunities for register-based research on these conditions. We assessed the validity and reliability of their ICD-10 codes in the Swedish National Patient Register (NPR).DesignRetrospective chart review.MethodsSix hundred individuals with a diagnosis of hypochondriasis or dysmorphophobia (300 each) were randomly selected from the NPR. Their medical files were requested from the corresponding clinics, located anywhere in Sweden. Two independent raters assessed each file according to ICD-10 definitions and Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision and Fifth Edition criteria. Raters also completed the Clinical Global Impression-Severity (CGI-S) and the Global Assessment of Functioning (GAF).Primary outcome measurePer cent between-rater agreement and positive predictive value (PPV). Intraclass correlation coefficients for the CGI-S and the GAF.ResultsEighty-four hypochondriasis and 122 dysmorphophobia files were received and analysed. The inter-rater agreement rate regarding the presence or absence of a diagnosis was 95.2% for hypochondriasis and 92.6% for dysmorphophobia. Sixty-seven hypochondriasis files (79.8%) and 111 dysmorphophobia files (91.0%) were considered 'true positive' cases (PPV=0.80 and PPV=0.91, respectively). CGI-S scores indicated that symptoms were moderately to markedly severe, while GAF scores suggested moderate impairment for hypochondriasis cases and moderate to serious impairment for dysmorphophobia cases. CGI-S and GAF inter-rater agreement were good for hypochondriasis and moderate for dysmorphophobia.ConclusionsThe Swedish ICD-10 codes for hypochondriasis and dysmorphophobia are sufficiently valid and reliable for register-based studies. The results of such studies should be interpreted in the context of a possible over-representation of severe and highly impaired cases in the register, particularly for dysmorphophobia.

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Validation of multiple sclerosis diagnoses in the Swedish National Patient Register.

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Validation of multiple sclerosis diagnoses in the Swedish National Patient Register.

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