VALIDATION OF THE CHAPTER "ALLERGIES AND HYPERSENSITIVITY" OF THE INTERNATIONAL DISEASE CLASSIFICATION (CIM)

Rationale for this Non-Interventional Study Allergic diseases, including allergic asthma, allergic rhinitis and anaphylaxis are not properly classified in current classifications of diseases. We here propose a project based on the evaluation of medical records of hospital databases of patients suffering for allergic and hypersensitivity conditions coded with the current and a new coming version of the international classification of diseases, no patient or intervention will be analized.

Objectives of this Non-Interventional Study Main Objectives: To assess the stability of codes for ICD-10 allergic diseases and hypersensitivity to ICD-11 using the medical-administrative databases of 3 hospitals.

Secondary Objectives: (I) To adjust the terms and links for allergic diseases and hypersensitivity and thus continue the on-line implementation process of ICD-11 based on the lessons learned on the main objective; (II) To estimate the economic impact of ICD-10 and ICD-11 transition for health care facilities; (III) To electronically align ICD-10 codes (and CM adaptation in the USA) with ICD-11.

Study design All the consecutive cases of allergies over a year and registered in the DIM bases of 3 healthcare establishments (the university hospital of Montpellier (CHRUM), Paris (APHP), Toulouse) will be individualized. Depending on the size of the facility, ½ to 1/10 of the cases will be included in the study. All cases will be selected anonymously. Two professional coders will encode the selected cases twice. The analysis of the data will be based on the degree of inter-encoder agreement using Cohen's Kappa coefficient. At the end of this process, we will be able to identify the correspondence between the codes recorded in the DIM database (ICD-10) and those of the new classification. In the event of discordant results, consensus will be reached by involving other coding experts from CHRUM. The economic impact of the transition from ICD-10 to ICD-11 will be approximated by estimating the average costs per ICD code used in the main diagnosis.

Target subject population Our project is focused on allergic and hypersensitivity sufferers. Although we intend to validate the classification of allergic and hypersensitivity conditions, the international classification systems are for global use and our methodology might be helpful for other diseases and for the program of medicalization and information system (PMSI).

Statistical methods In order to reach the inter and intra-variability testing, the data analysis will be based on the degree of inter-rater agreement using Cohen's Kappa.

The economic impact of the transition from ICD-10 to ICD-11 will be analized based on average estimated cost per day of each principal diagnosis and the effect of the classification change will be quantified by the cost variance of inter or intra diagnosis of ICD-10 and ICD-11.