Development of a classification system for drug-related problems in the hospital setting (APS-Doc) and assessment of the inter-rater reliability

What is known and Objective: Identifying, preventing and resolving drug-related problems (DRP) is an important issue in the pharmaceutical care process. Because DRPs have been detected in a more systematic way, the need for a classification system to document, classify and evaluate the collected data has become necessary. The objective was to develop a classification system for DRPs within the hospital setting, to evaluate the practicality and to assess the inter-rater reliability. Methods: All DRPs defined in PI-Doc and PCNE, which are relevant in the hospital setting, were included. Further relevant DRPs identified in other projects in a hospital setting as well as DRPs from the daily work on the ward were collected, and a short description of each DRP was written. A prospective study was conducted at Klinikum Fulda, Germany, in both a non-surgical and a surgical setting to explore whether the new classification system is suitable to classify DRPs in clinics with different specifications. For assessing the inter-rater reliability, 24 standardized case reports were provided. All participants classified them independently. The inter-rater reliability was analysed using Kappa coefficient. Results and Discussion: A classification system for DRPs in the hospital setting (APS-Doc) was established with 10 main categories and 48 subcategories. Practicality was assessed in 250 patients in a non-surgical ward as well as in 100 patients in a surgical ward. The inter-rater agreement was 0.68 (95% CI, 0.660.69) for main categories, which comprises substantial agreement. Moderate agreement (kappa = 0.58; 95% CI, 0.580.59) was demonstrated for the subcategories. What is new and Conclusion: A new hierarchical classification system for DRPs in the hospital setting has been developed. APS-Doc seems suitable for various parts of the medication process such as medication reconciliation and drug therapy within both non-surgical and surgical wards. Inter-rater reliability was found to be substantial in the main categories and moderate in the subcategories.