Metrics and tools for consistent cohort discovery and financial analyses post-transition to ICD-10-CM.

In the United States, International Classification of Disease Clinical Modification (ICD-9-CM, the ninth revision) diagnosis codes are commonly used to identify patient cohorts and to conduct financial analyses related to disease. In October 2015, the healthcare system of the United States will transition to ICD-10-CM (the tenth revision) diagnosis codes. One challenge posed to clinical researchers and other analysts is conducting diagnosis-related queries across datasets containing both coding schemes. Further, healthcare administrators will manage growth, trends, and strategic planning with these dually-coded datasets. The majority of the ICD-9-CM to ICD-10-CM translations are complex and nonreciprocal, creating convoluted representations and meanings. Similarly, mapping back from ICD-10-CM to ICD-9-CM is equally complex, yet different from mapping forward, as relationships are likewise nonreciprocal. Indeed, 10 of the 21 top clinical categories are complex as 78% of their diagnosis codes are labeled as "convoluted" by our analyses. Analysis and research related to external causes of morbidity, injury, and poisoning will face the greatest challenges due to 41 745 (90%) convolutions and a decrease in the number of codes. We created a web portal tool and translation tables to list all ICD-9-CM diagnosis codes related to the specific input of ICD-10-CM diagnosis codes and their level of complexity: "identity" (reciprocal), "class-to-subclass," "subclass-to-class," "convoluted," or "no mapping." These tools provide guidance on ambiguous and complex translations to reveal where reports or analyses may be challenging to impossible.Web portal: http://www.lussierlab.org/transition-to-ICD9CM/Tables annotated with levels of translation complexity: http://www.lussierlab.org/publications/ICD10to9.

Multicenter study comparing case definitions used to identify patients with chronic obstructive pulmonary disease.

RATIONALE: Clinical trials in chronic obstructive pulmonary disease (COPD) usually require evidence of airflow obstruction and clinical risk factors. International Classification of Diseases, Ninth Revision (ICD-9) diagnosis codes or patient-reported physician diagnoses are often used for epidemiologic studies and performance improvement programs. OBJECTIVES: To evaluate agreement between these case definitions for COPD and to assess the comparability of study populations identified as having COPD not using the clinical trial reference standard. METHODS: We recruited patients from the COPD Outcomes-based Network for Clinical Effectiveness and Research Translation multicenter clinical registry in a cross-sectional study. Demographics, clinical, and post-bronchodilator spirometry data were collected at an in-person study visit. The kappa statistic (κ) was used to evaluate agreement. A multivariable logistic regression model was used to identify patient characteristics associated with meeting the trial reference standard. MEASUREMENTS AND MAIN RESULTS: A total of 998 (82.8%) of 1,206 study participants met at least one case definition for COPD (of the 998: 91% using ICD-9 codes, 73% using patient-reported physician diagnosis, 56% using trial reference standard); agreement between case definitions was poor (κ = 0.20-0.26). Lack of airflow obstruction was the principal (89%) reason patients identified as having COPD did not meet the trial reference standard. Patients who were black (vs. white), obese (vs. normal weight), or had depression (vs. not) were less likely to meet the trial reference standard (odds ratio [95% CI], 0.37 [0.26-0.53], 0.51 [0.34-0.75], 0.53 [0.40-0.71], respectively). CONCLUSIONS: Findings highlight concerns about the applicability of findings in clinical trials to patients meeting other case definitions for COPD.