How good is the coverage and how accurate are exposure data in the Swedish Biologics Register (ARTIS)?
OBJECTIVE
To assess the coverage of the Swedish Biologics Register (Anti-Rheumatic Therapy in Sweden, ARTIS) across indications, and the accuracy of the registered information on treatment with biologics.


METHODS
Through cross-reference of ARTIS to almost complete national health registers on prescriptions (adalimumab and etanercept), outpatient visits, and death/residency during 2008-2010, we assessed: the treatment coverage of ARTIS for each treatment indication, the validity of the registered start and stop dates, ARTIS treatments with no corresponding drug dispensations, and the accuracy of the registered information on concomitant anti-rheumatic therapies.


RESULTS
According to the national health registers, 3945 individuals with a spondyloarthropathy (SpA) and 8032 patients with rheumatoid arthritis (RA) had filled at least one adalimumab or etanercept prescription during the study period. Of these, 86% of those with SpAs and 95% of patients with RA were also found in ARTIS with the corresponding treatment. Tumour necrosis factor (TNF) inhibitor prescriptions had been filled by 95% of patients between the ARTIS start and stop dates (allowing a 90-day window). More than 60 days before and more than 60 days after the registered start date in ARTIS, 5% and 4% respectively of patients had filled their first TNF inhibitor prescription. More than 90 days after the registered stop date in ARTIS, 8% of patients had filled one or more TNF inhibitor prescriptions.


CONCLUSIONS
We observed a high coverage and accuracy of ARTIS data on biologics exposure, for both SpAs and RA. The combination of data from clinical registers such as ARTIS with data from national health registers offers a high quality measurement of actual treatment.
Clinical Epidemiology Unit, Karolinska Institutet , Stockholm , Sweden.
H
H
Wadström
J K
JK
Eriksson
M
M
Neovius
J
J
Askling
D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D015535:Arthritis, Psoriatic / Q000188:drug therapy*; D001685:Biological Factors / Q000627:therapeutic use; D011307:Drug Prescriptions / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009313:National Health Programs; D010043:Outcome and Process Assessment, Health Care; D010355:Patient Identification Systems / Q000592:standards / Q000706:statistics & numerical data; D012042:Registries / Q000592:standards* / Q000706:statistics & numerical data; D025242:Spondylarthropathies / Q000188:drug therapy*; D013167:Spondylitis, Ankylosing / Q000188:drug therapy*; D013548:Sweden; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors
D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D001685:Biological Factors; D014409:Tumor Necrosis Factor-alpha