The validity of ICD codes coupled with imaging procedure codes for identifying acute venous thromboembolism using administrative data

Abstract

The purpose of this study was to evaluate the accuracy of using a combination of International Classification of Diseases (ICD) diagnostic codes and imaging procedure codes for identifying deep vein thrombosis (DVT) and pulmonary embolism (PE) within administrative databases. Information from the Alberta Health (AH) inpatients and ambulatory care administrative databases in Alberta, Canada was obtained for subjects with a documented imaging study result performed at a large teaching hospital in Alberta to exclude venous thromboembolism (VTE) between 2000 and 2010. In 1361 randomly-selected patients, the proportion of patients correctly classified by AH administrative data, using both ICD diagnostic codes and procedure codes, was determined for DVT and PE using diagnoses documented in patient charts as the gold standard. Of the 1361 patients, 712 had suspected PE and 649 had suspected DVT. The sensitivities for identifying patients with PE or DVT using administrative data were 74.83% (95% confidence interval [CI]: 67.01-81.62) and 75.24% (95% CI: 65.86-83.14), respectively. The specificities for PE or DVT were 91.86% (95% CI: 89.29-93.98) and 95.77% (95% CI: 93.72-97.30), respectively. In conclusion, when coupled with relevant imaging codes, VTE diagnostic codes obtained from administrative data provide a relatively sensitive and very specific method to ascertain acute VTE.

Automated versus Manual Data Extraction of the Padua Prediction Score for Venous Thromboembolism Risk in Hospitalized Older Adults

“…However, automated identification of PPS variables largely depends on the International Classification of Diseases 9th/10th Revision (ICD-9/10) coding. Given that diagnostic coding may be inaccurate or omit relevant conditions, [14][15][16][17][18][19] the performance of automated algorithms is unknown.…”

Incidence and Risk Factors for Deep Vein Thrombosis after Radiofrequency and Laser Ablation of the Lower Extremity Veins

“…In addition, administrative database codes to confirm a diagnosis of DVT may not always be reliable. Alotaibi et al found that administrative data was 75.2% sensitive and 95.8% specific for DVT, 25 with other studies showing similar findings. 26,27 The true incidence and clinical significance of DVT/EHIT are unable to be determined without evaluating clinic notes and radiographic files, which are unavailable in claims database.…”

Immigration, region of origin, and the epidemiology of venous thromboembolism: A population‐based study

“…First, we included over 2.2 million people with over 17 000 000 person-years of observation using comprehensive data linked from province-wide and federal administrative databases. We used a previously validated algorithm for identifying VTE events 6,7 and our overall IR for VTE is virtually identical to that reported in two recent Canadian studies in Quebec and Alberta. 11,12 We used a validated algorithm to determine ethnicity 5 derived from multiple comparisons.…”

“…Therefore, in this study we used algorithms comprising both diagnostic and procedural codes (i.e, imaging studies codes) with appropriate sensitivity and specificity to try to decrease the possibility of misclassification. 6,7,14 In spite of this, there is a possibility that a number of patients might have been missed or erroneously included.…”

“…A VTE diagnosis was based on a sensitive algorithm, as follows: (i) for a diagnosis of VTE as an outpatient, we required a combination of an OHIP Database diagnostic code for either DVT or PE and an OHIP fee code for leg ultrasound, ventilation-perfusion lung scan, or computed tomography pulmonary angiography-each within ±7 days of the other, or (ii) for inpatients, we required a combination of CIHI-DAD hospital discharge diagnosis of either DVT or PE and a diagnostic test procedure code in the same hospitalization. These algorithms have been previously validated in Canada (for both ICD 9 and 10 codes) with adequate sensitivity (>75%) and specificity (>90%) 6,7 ( Supplementary Table S3). The date of the VTE event was based on the first date in which a VTE diagnosis was recorded.…”