[Evaluation of medical information systems as a mean of identification of incident cases of colorectal cancer]. / Evaluation du PMSI comme moyen d'identification des cas incidents de cancer colorectal.

BACKGROUND: Cancer registries are a reliable source of data to estimate national cancer incidence rates, but they are not always available in all regions. This study assessed the value of medical information systems (PMSI) to identify incident cases of colorectal cancer METHODS: Two algorithms were elaborated to identify these incident cases in the PMSI database. The first algorithm was based on diagnosis and medical procedure codes and the second algorithm was based exclusively on diagnoses and the absence of diagnoses over the last five years. The results obtained for two departments were compared with those derived from two cancer registries, constituting the reference data. We then elaborated two multivariate logistic regression models to correct the national number of incident cases estimated by the algorithm adopted after evaluation of the results. RESULTS: The first algorithm provided results that were very close to those derived from the regional registries (646 vs 645 cases) with a good sensitivity and positive predictive value of 75%. The second algorithm overestimated the incidence by about 50% with a positive predictive value of 60% and was therefore not adopted for the national estimation. By applying the first algorithm to the national PMSI MCO database (medicine, surgery, obstetrics), and after modelling, the estimated incidence differed by only 2.34% compared to that observed by all 14 registries. The national estimation of cancer incidence was 39,122 [37,020; 41,224] cases for 2005, which is consistent with the figure published by the Francim national registry network (37,413). CONCLUSION: This study demonstrates the value of PMSI data for estimation of national incidence rates for certain cancers in the absence of cancer registries. However, raw data must be corrected and can be achieved by the method proposed here.

Medical record: systematic centralization versus secure on demand aggregation.

BACKGROUND: As patients often see the data of their medical histories scattered among various medical records hosted in several health-care establishments, the purpose of our multidisciplinary study was to define a pragmatic and secure on-demand based system able to gather this information, with no risk of breaching confidentiality, and to relay it to a medical professional who asked for the information via a specific search engine. METHODS: Scattered data are often heterogeneous, which makes the task of gathering information very hard. Two methods can be compared: trying to solve the problem by standardizing and centralizing all the information about every patient in a single Medical Record system or trying to use the data "as is" and find a way to obtain the most complete and the most accurate information. Given the failure of the first approach, due to the lack of standardization or privacy and security problems, for example, we propose an alternative that relies on the current state of affairs: an on-demand system, using a specific search engine that is able to retrieve information from the different medical records of a single patient. RESULTS: We describe the function of Medical Record Search Engines (MRSE), which are able to retrieve all the available information regarding a patient who has been hospitalized in different hospitals and to provide this information to health professionals upon request. MRSEs use pseudonymized patient identities and thus never have access to the patient's identity. However, though the system would be easy to implement as it by-passes many of the difficulties associated with a centralized architecture, the health professional would have to validate the information, i.e. read all of the information and create his own synthesis and possibly reject extra data, which could be a drawback. We thus propose various feasible improvements, based on the implementation of several tools in our on-demand based system. CONCLUSIONS: A system that gathers all of the currently available information regarding a patient on the request of health-care professionals could be of great interest. This low-cost pragmatic alternative to centralized medical records could be developed quickly and easily. It could also be designed to include extra features and should thus be considered by health authorities.

Watermarking - a new way to bring evidence in case of telemedicine litigation.

When dealing with medical data sharing, in particular within telemedicine applications, there is a need to ensure information security. Being able to verify that the information belongs to the right patient and is from the right source or that it has been rerouted or modified is a major concern. Watermarking, which is the embedding of security elements, such as a digital signature, within a document, can help to ensure that a digital document is reliable. However, at the same time, questions arise about the validity of watermarking-based proof. In this paper, beyond the technical aspects, we discuss the legal acceptability of watermarking in the context of telemedicine applications.

Empowerment of patients over their personal health record implies sharing responsibility with the physician.

Through this article, we point out the unavoidable empowerment of patients with regard to their personal health record and propose the mixed management of patients' medical records. This mixed management implies sharing responsibilities between the patient and the Medical Practitioner (MP) by making patients responsible for the validation of their administrative information, and MPs responsible for the validation of their patients' medical information. We propose a solution to gather and update patients' administrative and medical data in order to reconstitute patients' medical histories accurately. This method is based on two processes. The aim of the first process is to provide patients administrative data, in order to know where and when they received care (name of the health structure or health practitioner, type of care: outpatient or inpatient). The aim of the second process is to provide patients' medical information and to validate it under the responsibility of the MP with the help of patients if needed. During these two processes, the patients' privacy will be ensured through cryptographic hash functions like the Secure Hash Algorithm, which allows the pseudonymization of patients' identities. The Medical Record Search Engine we propose will be able to retrieve and to provide upon a request formulated by the MP all the available information concerning a patient who has received care in different health structures without divulging the patient's true identity. Associated with strong traceability of all access, modifications or deletions, our method can lead to improved efficiency of personal medical record management while reinforcing the empowerment of patients over their medical records.