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M O Carrere

Publications and source records attributed to M O Carrere.

6 recordsLinked to original sources

[Preliminary results of the assessment of intensity modulated radiotherapy (IMRT) for prostatic and head and neck tumors (STIC 2001)].

INTRODUCTION: Between May 2002 and May 2004, eight French comprehensive cancer centres did a prospective nonrandomized study including 200 patients, 100 with cancer of the prostate and 100 with head and neck cancers. Half of each patient group was treated by IMRT and the others by RTC 3D. This clinical study was associated with an economic study and a physics study. We report here the first results. PATIENTS AND METHODS: For the clinical study, the analysis of the data of the first 88 patients irradiated for a prostatic cancer shows that 39 received RTC and 49 IMRT with a mean dose of 78 Gy at the ICRU point at 2 Gy per fraction. For H&N tumours, the preliminary analysis was done on the 87 first patients with a mean follow-up of 11.5 months (2 to 25 months) and a median of 8.4 months for the IMRT groups and 13.2 months for the RTC group. The economic study was done on the first 157 patients included during the first 18 months: 71 treated by RTC (35 for H&N and 36 for prostate) and 86 treated by IMRT (38 for H&N and 48 for prostate). The assessment of the direct costs was realized by a micro-costing technique. The physical study compared dose distributions for both techniques and has created quality control recommendations. RESULTS: Clinical studies of the acute reactions do not show any difference between groups, but we want to point out the short follow-up and the relatively high dose delivered to cancers of the prostate. The physics study demonstrates that IMRT is technically feasible in good clinical conditions with high quality assurance, a good reproducibility and precision. Dosimetric data show that IMRT could certainly spare organs at risk more than RTC for H&N tumours. The direct costs of "routine" treatments for H&N tumours were 4922 euros for IMRT versus 1899 euros for RTC and for the prostatic cancers 4911 euros for IMRT versus 2357 for RTC.

Adolescent↗

[Intensity modulated radiotherapy (IMRT) in France: The boost of the national funding for the new expensive innovative technologies (STIC 2001 and 2002)].

The STIC 2001 and STIC 2002 projects intend to allow the implementation and the assessment of Intensity Modulated Radiation Therapy in France. IMRT is an innovative technique in which the high-dose radiation volume conforms to an accurately defined target volume with less morbidity to the surrounding normal tissues. The main medical objectives of the projects are (1) to improve the therapeutic index while decreasing acute toxicity and late sequelae (mainly xerostomia and acute mucite for head and neck tumors), which allows an increase in the radiation dose to the tumor and then a better tumor control; (2) to propose a salvage treatment to patients who locally recurred in previously irradiated sites; (3) to determine the optimal treatment guidelines for a safe use of the technique in clinical routine. Our projects also aim at comparing IMRT and 3D conformal treatments on the one hand (STIC 2001), and IMRT and conventional treatments on the other hand (STIC 2002), with regard to costs. As a matter of fact, the use of IMRT is presently limited in France because its implementation requires high investment and personnel costs. The seventeen French Regional Cancer Centres involved in the two projects intend to study the additional cost of the use IMRT in comparison with the use of standard techniques, which appears to be a step for a wide use of this technique in France. Each of the studies is two-year prospective, and includes patients with head and neck tumors treated with a curative intend (post operative or exclusive treatments for STIC 2002 and STIC 2002), and patients with a prostate cancer (STIC 2001).

Adult↗

[How to evaluate the quality of information transfer from physician to patient? Choice of psychometric tests for a decision tree in a Regional Cancer Centre].

BACKGROUND: Decision boards are used to transfer information from physicians to patients to help them participate in the clinical decision-making process. We present the tests and results of the psychometric properties of a decision board in a sample of healthy volunteers. METHODS: In the Regional Cancer Centre located in Lyon, we developed a decision board for post-menopausal women with breast cancer after lumpectomy without any poor prognostic factors. Two treatment options were proposed, one involving chemotherapy and the other not. We tested for the following psychometric properties: comprehension, construct validity and reliability. Comprehension was evaluated using a questionnaire, in order to test whether the rates of correct answers were due to chance alone. The construct validity was assessed by changing the information provided (relapse and survival rates, characteristics of chemotherapy) and testing whether the proportion of healthy volunteers choosing an option changed in a predictable and significant way. The reliability was evaluated using the test-retest method. Two reliability statistics were computed: the Pearson correlation and the Intraclass Correlation Coefficient. RESULTS: In the sample of 40 healthy volunteers, 23 chose the option with chemotherapy and 17 the option without chemotherapy. Results show that the decision board was comprehensive, valid (the women changed their choices in a predictable way) and reliable (Pearson correlation and Intraclass Correlation Coefficient close to 1). CONCLUSION: The choice of the psychometrics properties tested and the statistical tests used are discussed. The psychometric properties of our tool are found to be satisfactory.

Aged↗

Is Helicobacter pylori eradication a cost-effective treatment of duodenal ulcer disease?

Treatment strategies aimed at eradicating Helicobacter pylori have shown positive results in the management of duodenal ulcer disease. Several cost-effectiveness studies comparing these regimens with traditional therapy have recently been conducted, and results are discussed in this review. Cost comparisons of different treatment strategies cannot be performed without first identifying whether the cost of ulcer diagnosis is included in the study. Assuming that only 20% of patients with dyspepsia actually have ulcer disease, costs may vary, depending on the study population. Importantly, treatment costs should not be compared between a patient population with confirmed ulcer disease and one without confirmed disease. In patients with confirmed ulcer disease, studies consistently show that H. pylori eradication strategies are associated with greater efficacy and lower costs than traditional treatment, and are therefore a more cost-effective alternative to standard therapy. Although all models used in the cost-effectiveness analyses assume that patients discontinue treatment following successful eradication of the microorganism, in clinical practice some patients continue antisecretory treatment beyond this period. Thus, savings as a result of H. pylori eradication may be less substantial than indicated in cost-effectiveness studies.

Cost-Benefit Analysis↗

The reaction of private physicians to price deregulation in France.

French private physicians are paid on a fee-for-service basis and nearly all of them are under contract to the Social Security, which refunds part of the medical fee to the whole population. Previously the prices of medical services were fixed, but since 1980, a new option has been possible: a doctor can choose to fix the price of his services freely, provided he pays a higher social insurance contribution. But the amount refunded by Social Security does not vary, so that the consumer has to bear the extra charge. Our purpose here is to identify the factors that influence the physician's option. In Section 2, we define a model of the private physician's economic behaviour, of the classic income-leisure type. In Section 3, empirical tests are performed on a sample of observations in 95 'départements', gathering information about private GPs on the one hand, and the whole population on the other. According to our results, GPs' decisions depend on characteristics of both supply of and demand for GPs' services. One of our conclusions is that GPs seem to make up for low activity levels with higher prices, on condition the income of their practice allows it.

Choice Behavior↗

Shared decision-making in question.

Over recent years, communication within the physician-patient relationship has been profoundly changing. New modes of conveying diagnostic and therapeutic information influence the way in which decisions regarding treatment are made. We propose a critical review of the various theoretical models as presented in the literature, from the paternalistic to the shared decision model, in order to reveal conceptual ambiguities and their related methodological problems. This analysis leads to a project for clarifying these problems through a research protocol based on shared decision-making.

Communication↗