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Vittorio Demicheli

Publications and source records attributed to Vittorio Demicheli.

11 recordsLinked to original sources
PubMed2005

Incidence of vaccine preventable pneumococcal invasive infections and blood culture practices in Italy.

In order to estimate the incidence of invasive pneumococcal diseases (IPD) and the amount of vaccine preventable serious infections, a 1-year population-based surveillance was undertaken in two comparable Italian regions (Piemonte and Puglia, representing 14% of the Italian population) prospectively collecting data and strains from all the hospital microbiological laboratories. A retrospective analysis of hospital discharge records, matched with the laboratory database, was also undertaken in nine hospitals in these two regions to determine the frequency of use of blood cultures and its impact on IPD incidence estimate. For children under 2 years of age, the incidence rates of IPD were 11.3 per 100,000 and 5.9 per 100,000 in Piemonte and in Puglia, respectively; for subjects 65 years of age and over the incidence rates were 5.7 per 100,000 and 0.2 per 100,000, in the two regions, respectively. The number of blood cultures performed was six times higher in Piemonte than that in Puglia. About 96% of isolates from IPD patients, aged 65 years and over, belonged to serogroups included in the 23-valent polysaccharide vaccine, whereas about 79% of strains isolated from patients under 5 years of age were related to serotypes included in the 7-valent conjugate vaccine. The estimate of the incidence of IPD is affected greatly by the different attitudes in performing blood cultures, especially in older patients. In Italy, bacteriological culture procedures should be undertaken more frequently to provide decision-makers with reliable estimates of serious vaccine preventable conditions.

Adolescent↗
PubMed2003

Unintended events following immunization with MMR: a systematic review.

Public debate over the safety of the trivalent measles, mumps and rubella (MMR) vaccine and the drop in vaccination rates in several countries persists despite its almost universal use and accepted effectiveness. We carried out a systematic review to assess the evidence of unintended effects (beneficial or harmful) associated with MMR and the applicability of systematic reviewing methods to the field of safety evaluation. Eligible studies were comparative prospective or retrospective on healthy individuals up to 15 years of age, carried out or published by 2003. We identified 120 articles satisfying our inclusion criteria and included 22. MMR is associated with a lower incidence of upper respiratory tract infections, a higher incidence of irritability, similar incidence of other adverse effects compared to placebo and is likely to be associated with benign thrombocytopenic purpura (TP), parotitis, joint and limb complaints and aseptic meningitis (mumps Urabe strain-containing MMR). Exposure to MMR is unlikely to be associated with Crohn's disease, ulcerative colitis, autism or aseptic meningitis (mumps Jeryl-Lynn strain-containing MMR). The design and reporting of safety outcomes in MMR vaccine studies, both pre- and post-marketing, are largely inadequate. The evidence of adverse events following immunization with MMR cannot be separated from its role in preventing the target diseases.

Bias↗
PubMed2003

The effectiveness and safety of hepatitis A vaccine: a systematic review.

We report on the conduct of a systematic review to assess the efficacy and the safety of hepatitis A vaccines in adults and children. We identified, retrieved, and assessed all trials evaluating the effects of hepatitis A vaccines on prevention of cases of hepatitis A, death from hepatitis A, and assessing nature and frequency of adverse events. We included eight randomised trials, four containing efficacy outcomes, three containing only safety outcomes and a single study containing efficacy and adverse events outcomes. Combined inactivated vaccine effectiveness was 86% (95% CI: 63-95%). Combined attenuated vaccine effectiveness was 95% (95% CI: 81-99%). Inactivated vaccine effectiveness in the prevention of HAV secondary cases, compared to non-intervention was 82% (95% CI: 23-96%). Safety profile of vaccines was similar to that of their comparators. Despite poor design and reporting of trials, we found convincing evidence of the effectiveness and safety of inactivated HAV vaccines.

Hepatitis A↗
PubMed2003

The use of hepatitis a vaccination in Italy: an economic evaluation.

We report on the conduct and results of an economic model of two different strategies of vaccination against hepatitis A in Italy. In strategy 1 (universal vaccination), all newborns are vaccinated simultaneously with MMR at 15 months and all 12 year olds are vaccinated with combined hepatitis A and B vaccine. In strategy 2 (contacts' vaccination) only subjects with a close social and spatial relationship with the sick are vaccinated. In strategy 1 costs per avoided case and net costs per avoided case values are always very high. Net costs become very low when newborns and 12 year olds are vaccinated, and become negative (indicating a potential gain) when 12 year olds are vaccinated. From an economic viewpoint, universal vaccination appears recommendable only in epidemic conditions. For strategy 2 our model shows that cost for avoidable case are very low and net costs for avoided case are always negative, showing the potential presence of an absolute benefit. We conclude that in Italy mass vaccination appears economically worthwhile only during epidemics but vaccination of contacts is an economically worthwhile routine measure.

Costs and Cost Analysis↗
PubMed2002

Quality of systematic reviews of economic evaluations in health care.

CONTEXT: Reviews performed almost a decade ago showed considerable gaps in the quality of reporting and methods applied to economic evaluations of health care interventions. Measures taken by the research community to address the issue included the promulgation of guidelines and the publicizing of good practice in economic evaluation. METHODS: To assess the quality of methods of systematic reviews, economic evaluations in health care, and reporting methods, we conducted full-text searches of private and public databases for the period 1990 through March 2001 and corresponded with researchers active in the field. A total of 102 reports were identified, but only 39 were included. Quality of systematic reviews was assessed by a 6-item checklist. RESULTS: Quality of review methods was reasonable, but more attention needs to be paid to search methods and standardization of evaluation instruments. The reviews found consistent evidence of serious methodological flaws in a significant number of economic evaluations. Lack of clear descriptions of methods, lack of explanation and justification for the framework and approach used, and low-quality estimates of effectiveness for the interventions evaluated were the most frequent flaws. Modest improvements in quality of conducting and reporting economic evaluations appear to have taken place in the last decade. CONCLUSIONS: Proper allocation of resources on the basis of economic evaluations remains uncertain. Editorial teams and regulatory bodies should perform quality assurance based on a single widely accepted and validated standard instrument.

Cost-Benefit Analysis↗
PubMedDate not supplied

[Conflict of interest in industry-funded medical research].

OBJECTIVES: to assess the impact of the source of funding on the results of medical research. DESIGN: review of systematic reviews on this subject. MAIN OUTCOME MEASURES: relationship between source of funding and studies' conclusions. RESULTS: twenty reviews of studies dealing with many different medical intervention were identified and included. The definitions of the source of funding varied largely across the studies and the information on funding available in the primary studies were generally judged as inaccurate and insufficient to identify the source. Some studies assessed the relationship between funding and methodological quality of the research and found no difference between industry funded and other studies. The majority of the studies included demonstrated the existence of a significant association between source of funding and results of the research showing that the studies financed by industry are more likely to conclude in favour of the intervention produced by the funding bodies. A meta-analysis was carried out on 18 of the twenty studies. Pooled Relative Risk was 1.58 (95% CI: 1.39 to 1.80) confirming the existence of a significant association and homogeneous results across different studies. CONCLUSION: future reviews should seek for information regarding sources of funding of included studies and account for it in interpreting their results.

Biomedical Research↗