The DOI matches its Crossref record; 23 of the 23 references it cites were found in a registry or an index.
Adaptation of the Charlson Comorbidity Index for Register-Based Research in Sweden
Open accessAbstract
PURPOSE: Comorbidity indices are often used to measure comorbidities in register-based research. We aimed to adapt the Charlson comorbidity index (CCI) to a Swedish setting. METHODS: Four versions of the CCI were compared and evaluated by disease-specific experts. RESULTS: We created a cohesive coding system for CCI to 1) harmonize the content between different international classification of disease codes (ICD-7,8,9,10), 2) delete incorrect codes, 3) enhance the distinction between mild, moderate or severe disease (and between diabetes with and without end-organ damage), 4) minimize duplication of codes, and 5) briefly explain the meaning of individual codes in writing. CONCLUSION: This work may provide an integrated and efficient coding algorithm for CCI to be used in medical register-based research in Sweden.
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Coding algorithms for defining comorbidities in ICD-9-CM and ICD-10 administrative data
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Adapting a clinical comorbidity index for use with ICD-9-CM administrative databases
DEYO, R. (1992) · Journal of Clinical Epidemiology · doi:10.1016/0895-4356(92)90133-8 · Cited by 10,452
Wettermark, B., Hammar, N., MichaelFored, C., Leimanis, A., Otterblad Olausson, P., Bergman, U., Persson, I., Sundström, A., Westerholm, B., & Rosén, M. (2007) · Pharmacoepidemiology and Drug Safety · doi:10.1002/pds.1294 · Cited by 1,887
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Risk Adjustment in Outcome Assessment: the Charlson Comorbidity Index
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Milk intake and risk of mortality and fractures in women and men: cohort studies
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Self-citationA systematic review identifies valid comorbidity indices derived from administrative health data
Yurkovich, M., Avina-Zubieta, J. A., Thomas, J., Gorenchtein, M., & Lacaille, D. (2015) · Journal of Clinical Epidemiology · doi:10.1016/j.jclinepi.2014.09.010 · Cited by 358
Ethical aspects of registry-based research in the Nordic countries
Ludvigsson, J., Nørgaard, M., Weiderpass, E., Håberg, S., LaFolie, P., Sarkkola, C., von Kraemer, S., Zoega, H., & Knudsen, G. P. (2015) · Clinical Epidemiology · doi:10.2147/clep.s90589 · Cited by 357
Self-citationReview of 103 Swedish Healthcare Quality Registries
Emilsson, L., Lindahl, B., Köster, M., Lambe, M., & Ludvigsson, J. F. (2015) · Journal of Internal Medicine · doi:10.1111/joim.12303 · Cited by 351
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Katsoularis, I., Fonseca-Rodríguez, O., Farrington, P., Lindmark, K., & Fors Connolly, A.-M. (2021) · The Lancet · doi:10.1016/s0140-6736(21)00896-5 · Cited by 582
Learning the natural history of human disease with generative transformers
Shmatko, A., Jung, A. W., Gaurav, K., Brunak, S., Mortensen, L. H., Birney, E., Fitzgerald, T., & Gerstung, M. (2025) · Nature · doi:10.1038/s41586-025-09529-3 · Cited by 110
Perinatal depression and risk of mortality: Nationwide, register-based study in Sweden
Hagatulah, N., Bränn, E., Oberg, A. S., Valdimarsdóttir, U. A., Shen, Q., & Lu, D. (2024) · BMJ · doi:10.1136/bmj-2023-075462 · Cited by 72
“33 Additionally, we estimated the association by time since pregnancy for antepartum depression (within 13 weeks or 14 weeks onwards) and by time since delivery for postpartum depression (within six months or 7-12 months).”
MethodMetabolic syndrome traits increase the risk of major adverse liver outcomes in type 2 diabetes
Shang, Y., Grip, E. T., Modica, A., Skröder, H., Ström, O., Ntanios, F., Gudbjörnsdottir, S., & Hagström, H. (2024) · Diabetes Care · doi:10.2337/dc23-1937 · Cited by 61
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Metadata
- Authors
- Ludvigsson, J. F., Appelros, P., Askling, J., Byberg, L., Carrero, J.-J., Ekström, A. M., Ekström, M., Smedby, K. E., Hagström, H., James, S., Järvholm, B., Michaelsson, K., Pedersen, N. L., Sundelin, H., Sundquist, K., & Sundström, J.
- Venue
- Clinical Epidemiology
- Publisher
- Informa UK Limited
- Published
- 2021-01
- Volume
- Volume 13
- Pages
- 21-41
- ISSN
- 1179-1349 (ISSN-L)
- OpenAlex
- W3119800676
- Cited by
- 284
- References
- 23
- FWCI
- 24.36
- Type
- journal article
- Language
- en
- Open access
- gold
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- Ludvigsson, J. F., Appelros, P., Askling, J., Byberg, L., Carrero, J.-J., Ekström, A. M., Ekström, M., Smedby, K. E., Hagström, H., James, S., Järvholm, B., Michaelsson, K., Pedersen, N. L., Sundelin, H., Sundquist, K., & Sundström, J. (2021). Adaptation of the Charlson Comorbidity Index for Register-Based Research in Sweden. Clinical Epidemiology. https://doi.org/10.2147/clep.s282475
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