Development and validation of novel algorithms to identify patients with inflammatory bowel diseases in Israel: an epi-IIRN group study

Abstract

BackgroundBefore embarking on administrative research, validated case ascertainment algorithms must be developed. We aimed at developing algorithms for identifying inflammatory bowel disease (IBD) patients, date of disease onset, and IBD type (Crohn’s disease [CD] vs ulcerative colitis [UC]) in the databases of the four Israeli Health Maintenance Organizations (HMOs) covering 98% of the population.MethodsAlgorithms were developed on 5,131 IBD patients and 2,072 controls, following independent chart review (60% CD and 39% UC). We reviewed 942 different combinations of clinical parameters aided by mathematical modeling. The algorithms were validated on an independent cohort of 160,000 random subjects.ResultsThe combination of the following variables achieved the highest diagnostic accuracy: IBD-related codes, alone if more than five to six codes or combined with purchases of IBD-related medications (at least three purchases or ≥3 months from the first to last purchase) (sensitivity 89%, specificity 99%, positive predictive value [PPV] 92%, negative predictive value [NPV] 99%). A look-back period of 2–5 years (depending on the HMO) without IBD-related codes or medications best determined the date of diagnosis (sensitivity 83%, specificity 68%, PPV 82%, NPV 70%). IBD type was determined by the majority of CD/UC codes of the three recent contacts or the most recent when less than three contacts were recorded (sensitivity 92%, specificity 97%, PPV 97%, NPV 92%). Applying these algorithms, a total of 38,291 IBD patients were residing in Israel, corresponding to a prevalence rate of 459/100,000 (0.46%).ConclusionThe application of the validated algorithms to Israel’s administrative databases will now create a large and accurate ongoing population-based cohort of IBD patients for future administrative studies.

The use of ICD codes to identify IBD subtypes and phenotypes of the Montreal classification in the Swedish National Patient Register

“…Using these definitions, we observed PPVs of 97% for prevalent Crohn's disease and 98% for prevalent ulcerative colitis. The observed level of accuracy for Crohn's disease and ulcerative colitis is higher than among most previous reports [6,9,[19][20][21][22][23]. However, this difference is partly explained by differences in study design, as we included patients with known IBD who were treated with biologics and not a random subset of patients with IBD-associated ICD-codes in a national or regional register.…”

COVID-19 Prevalence and Mortality Among Schizophrenia Patients: A Large-Scale Retrospective Cohort Study

“…Diagnoses and medical fields were obtained through the chronic diseases registry, which has been previously validated by the developers of its algorithms, 13 as well as by many other authors utilizing the database. 14–17 The establishment of the computerized systems was initiated in 2000 and is continuously updated with clinical information. The extraction of the current database, containing schizophrenia patients and their matched controlled cases, was originally mined at the end of 2017.…”

Risk of intestinal and extra-intestinal cancers in patients with inflammatory bowel diseases: A population-based cohort study in northeastern Italy

“…Nevertheless, we are confident that the combined use of three different sources of administrative databases of the Friuli Venezia Giulia regionwhich have served as sources for several published research articles [41][42][43]-have allowed reaching a large group of IBD patients with different types of access to health services. Indeed, hospital discharge records have been largely used in many studies for IBD case ascertainment [44][45][46] while inclusion of medical exemptions has been effectively used in previous studies on IBD or other chronic conditions [45,47]. Furthermore, pathological archives were included in a recent investigation [48].…”