Socioeconomic inequalities in health status and survival: a cohort study in Rome.

OBJECTIVES: To analyse the association between individual and contextual socioeconomic position (SEP) with health status and to investigate the role of SEP and baseline health status on survival. DESIGN: Cross-sectional and cohort study. SETTING: Rome, Italy. PARTICIPANTS, PRIMARY AND SECONDARY OUTCOMES: We selected the 25-99 year-olds included in the Rome 2011 census cohort. As a measure of health status on the census reference date (09 October 2011), we used the presence of chronic or rare conditions from the Disease-Related Co-payment Exemption Registry, a database implemented to provide free care to people with chronic or rare diseases. We used logistic regression to analyse the association between both individual (educational attainment) and contextual SEP (neighbourhood real estate price quintiles) with baseline health status. We analysed the role of SEP and the presence of chronic or rare conditions on 5-year survival (until 31 December 2016) using accelerated failure time models with Weibull distribution, reporting time ratios (TRs; 95% CI). RESULTS: In middle-aged, subjects with low SEP (either individual or contextual) had a prevalence of chronic conditions comparable with the prevalence in high SEP individuals 10 years older. Adjusted logistic models confirmed the direct association between SEP and baseline health status in both women and men. The lowest educated were up to 67% more likely to have a chronic condition than the highest educated, while the difference was up to 86% for lowest versus highest contextual SEP. Low SEP and the presence of chronic conditions were associated with shorter survival times in both sexes, lowest versus highest educated TR was TR=0.79 for women (95% CI: 0.77 to 0.81) and TR=0.71 for men (95% CI: 0.70 to 0.73). The contextual SEP shrunk survival times by about 10%. CONCLUSION: Inequalities were present in both baseline health and survival. The association between SEP and survival was independent of baseline health status.

A nationwide survey of Italian Centers for Cognitive Disorders and Dementia on the provision of care for international migrants.

BACKGROUND: More than 500,000 dementia cases can be estimated among migrants living in Europe. There is the need to collect "real world" data on the preparedness of healthcare services to support the inclusion of migrants in the public health response to dementia. The present study aimed (i) to estimate the number of migrants referred to Italian memory clinics (Centers for Cognitive Disorders and Dementia [CCDDs]) and (ii) to identify possible barriers and resources for the provision of diversity-sensitive care. METHODS: A survey of all Italian CCDDs was conducted between December 2020 and April 2021. An online questionnaire was developed to obtain information on the number of migrants referred to Italian CCDDs in 2019, the challenges encountered in the diagnostic approach, and possible facilitators in the provision of care. RESULTS: Overall, 343 of the 570 contacted CCDDs completed the survey questionnaire (response rate: 60.2%). Nearly 4527 migrants were referred to these services in 2019. Migrants accounted for a median 1.1% (IQR: 0.9%-2.8%) of overall CCDD referrals. More than one-third of respondents reported that the number of migrants referred to their facilities had increased in the last 5 years. The overall quality of the migrants' cognitive assessment was deemed to be very poor or insufficient in most cases. A minority of CCDDs had translated information material on dementia and reported the possibility to contact cultural mediators and interpreters. CONCLUSIONS: A relevant number of migrants are being referred to Italian CCDDs that are still not adequately prepared to deliver diversity-sensitive care and support.

Dementia among migrants and ethnic minorities in Italy: rationale and study protocol of the ImmiDem project.

INTRODUCTION: Due to the ongoing demographic and epidemiological transitions, estimating the phenomenon of dementia in migrants and minority groups, exploring its characteristics and challenges and implementing dedicated healthcare policies, constitute emerging and urgent matters for Western countries. In the present paper we describe the rationale and design of the 'Dementia in immigrants and ethnic minorities living in Italy: clinical-epidemiological aspects and public health perspectives" (ImmiDem) project. METHODS AND ANALYSIS: Three main aims will be pursued by the ImmiDem project. First, a survey of all Italian dementia services will be conducted with dedicated questionnaires in order to estimate and describe the proportion and characteristics of migrants seeking help for cognitive disturbances. The different clinical approaches for diagnosing dementia and the challenges encountered in the assessment of cognitive functioning and in the provision of care in these groups of individuals will also be investigated. Second, record linkage procedures of data routinely collected in regional Health Information Systems will be conducted in order to identify and monitor migrant individuals with dementia living in the Lazio region. Third, tailored national and local care-coordination pathways and/or good practices dedicated to migrants affected by dementia and cognitive disorders will be identified and promoted. ETHICS AND DISSEMINATION: The study protocol was approved by the Ethics Committee of the Italian National Institute of Health (protocol 10749; 5 April 2018). The project was launched in November 2018 and will end in November 2021. The findings of the project will be disseminated through scientific peer-reviewed journals as well as to the public via the Dementia Observatory website (https://demenze.iss.it).

[Urban health and inequalities in highly socially marginalised settings in Rome]. / Salute urbana e disuguaglianze a Roma in contesti a elevata marginalità sociale.

OBJECTIVES: to describe hospitalisation, access to emergency care, and mortality of people living in marginalized urban areas which include public housing buildings in the North-West suburb of Rome, and to compare the results with those observed among people living in the neighbouring area. DESIGN: cross sectional study. SETTING AND PARTICIPANTS: resident population in the XIII and XIV Municipality of Rome, subdivided into five urban areas, in 2011-2018. MAIN OUTCOME MEASURES: hospitalisation, access to emergency care, and mortality rates and rates ratios based on hospital discharges and emergency department visits derived from the Health Information Systems and from the Mortality Registry of Lazio Region (Central Italy), stratified by urban areas. RESULTS: the results show a higher use of hospital assistance and emergency care services as well a higher mortality among residents of urban areas characterized by marginalization and social disadvantage in the North-West suburb in Rome, compared to the surrounding area. The association is stronger for the residents of ex-Bastogi, a compound particularly marginalised and socially disadvantaged, where excesses in hospitalisation, emergency care admission, and mortality of +60%, +150%, and +140%, respectively, occurred. CONCLUSIONS: the excesses of hospital use, emergency care visits, and mortality observed among the residents of marginalized urban areas suggest the need to reorganize the preventive and primary care services considering the socioeconomic disadvantage in such housing contexts. The use of both qualitative and quantitative approaches allows to understand the complexity of such contexts.

[Immigrants' health and socioeconomic inequalities of overall population residing in Italy evaluated through the Italian network of Longitudinal Metropolitan Studies]. / Salute degli immigrati e disuguaglianze socioeconomiche nella popolazione residente in Italia valutate attraverso la rete degli Studi Longitudinali Metropolitani.

INTRODUCTION: Describing and monitoring socioeconomic inequalities in health are the prerequisite for planning equity policies. In Italy, some cities have integrated personal information from the municipal registries with Census data and with data from healthcare information systems to set up Longitudinal Metropolitan Studies (LMS). Under the coordination of the Italian National Institute for Health, Migration, and Poverty (NIHMP), six cities in the LMS network have contributed to the present monograph: Turin, Venice, Reggio Emilia, Modena, Bologna, and Rome. MORTALITY RESULTS. Significant socioeconomic differences by level of education were seen in all the participating centres. People who live alone or in single-parent households are more likely to die, as are those living in a substandard dwelling. Immigrants resident in the six cities included in the study showed lower all-cause mortality than Italians (males: MRR 0.83; 95%CI 0.78-0.90 - females: MRR 0.70; 95%CI 0.64-0.77). Sub-Saharan Africans experienced a significant higher mortality than Italians (males: MRR 1.33; 95%CI 1.12-1.59 - females: MMR 1.69; 95%CI 1.31-2.17). Immigrants had a neonatal and post-neonatal mortality risk about 1.5 times higher than Italians (neonatal: OR 1.71; 95%CI 1.22-2.39 - post-neonatal: OR 1.63; 95%CI 1.03-2.57). A difference between Italians and immigrants was also observed for mortality in children aged 1-4 years, though less marked (OR 1.24; 95%CI 0.73-2.11). Excesses concerned particularly immigrants from North Africa and from sub-Saharan Africa as well as those residing in Italy for >5 years. HOSPITALISATION RESULTS. Hospitalisation rates are lower for immigrants than for Italians, except when due to infectious diseases, blood disorders, and, among women, for reasons linked to pregnancy and childbirth. Avoidable hospitalisation rates of adults from low migratory pressure Countries are lower than or equal to those of Italians. On the contrary, adults from low migratory pressure Countries show higher avoidable hospitalisation rates compared to Italians in every cohort, with the exception of Rome (RR 0.81; 95%CI 0.78-0.85), with RR ranging from 1.08 (95%CI 0.96-1.22) in Venice to 1.64 (95%CI 1.47-1.83) in Modena. CONCLUSIONS: Maternal and child health is the most critical area of health for immigrant population. Considering the importance that the issue of health equity has taken on in the political agenda, the data presented in this volume are a great asset, particularly in light of the long recession and the social crisis that have impacted the Country.

A Systematic Review of Case-Identification Algorithms Based on Italian Healthcare Administrative Databases for Three Relevant Diseases of the Nervous System: Parkinson's Disease, Multiple Sclerosis, and Epilepsy.

BACKGROUND: Parkinson's Disease (PD), Multiple Sclerosis (MS), and Epilepsy are three highly impactful health conditions affecting the nervous system. PD, MS, and epilepsy cases can be identified by means of Healthcare Administrative Databases (HADs) to estimate the occurrence of these diseases, to better monitor the adherence to treatments, and to evaluate patients' outcomes. Nevertheless, the absence of a validated and standardized approach makes it hard to quantify case misclassification. OBJECTIVES: to identify and describe all PD, MS, and epilepsy case-identification algorithms by means of Italian HADs, through the review of papers published in the past 10 years. METHODS: this study is part of a project that systematically reviewed case-identification algorithms for 18 acute and chronic conditions by means of HADs in Italy. PubMed was searched for original articles, published between 2007 and 2017, in Italian or English. The search string consisted of a combination of free text and MeSH terms with a common part that focused on HADs and a disease-specific part. All identified papers were screened by two independent reviewers. Pertinent papers were classified according to the objective for which the algorithm had been used, and only articles that used algorithms for primary objectives (I disease occurrence; II population/cohort selection; III outcome identification) were considered for algorithm extraction. The HADs used (hospital discharge records, drug prescriptions, etc.), ICD-9 and ICD-10 codes, ATC classification of drugs, follow-back periods, and age ranges applied by the algorithms have been reported. Further information on specific objective(s), accuracy measures, sensitivity analyses and the contribution of each HAD, have also been recorded. RESULTS: the search strategy led to the identification of 70 papers for PD, 154 for MS, and 100 for epilepsy, of which 3 papers for PD, 6 for MS, and 5 for epilepsy were considered pertinent. Most articles were published in the last three years (2014-2017) and focused on a region-wide setting. Out of all pertinent articles, 3 original algorithms for PD, 4 for MS, and 4 for epilepsy were identified. The Drug Prescription Database (DPD) and Hospital Discharge record Database (HDD) were used by almost all PD, MS, and epilepsy case-identification algorithms. The Exemption from healthcare Co-payment Database (ECD) was used by all PD and MS case-identification algorithms, while only 1 epilepsy case-identification algorithm used this source. All epilepsy case-identification algorithms were based on at least a combination of electroencephalogram (EEG) and drug prescriptions. An external validation had been performed by 2 papers for MS, 2 for epilepsy, and only 1 for PD. CONCLUSION: the results of our review highlighted the scarce use of HADs for the identification of cases affected by neurological diseases in Italy. While PD and MS algorithms are not so heterogeneous, epilepsy case-identification algorithms have increased in complexity over time. Further validations are needed to better understand the specific characteristics of these algorithms.

Quality improvement strategies at primary care level to reduce inequalities in diabetes care: an equity-oriented systematic review.

BACKGROUND: There is evidence that disparities exist in diabetes prevalence, access to diabetes care, diabetes-related complications, and the quality of diabetes care. A wide range of interventions has been implemented and evaluated to improve diabetes care. We aimed to review trials of quality improvement (QI) interventions aimed to reduce health inequities among people with diabetes in primary care and to explore the extent to which experimental studies addressed and reported equity issues. METHODS: Pubmed, EMBASE, CINAHL, and the Cochrane Library were searched to identify randomized controlled studies published between January 2005 and May 2016. We adopted the PROGRESS Plus framework, as a tool to explore differential effects of QI interventions across sociodemographic and economic factors. RESULTS: From 1903 references fifty-eight randomized trials met the inclusion criteria (with 17.786 participants), mostly carried out in USA. The methodological quality was good for all studies. Almost all studies reported the age, gender/sex and race distribution of study participants. The majority of trials additionally used at least one further PROGRESS-Plus factor at baseline, with education being the most commonly used, followed by income (55%). Large variation was observed between these studies for type of interventions, target populations, and outcomes evaluated. Few studies examined differential intervention effects by PROGRESS-plus factors. Existing evidence suggests that some QI intervention delivered in primary care can improve diabetes-related health outcomes in social disadvantaged population subgroups such as ethnic minorities. However, we found very few studies comparing health outcomes between population subgroups and reporting differential effect estimates of QI interventions. CONCLUSIONS: This review provides evidence that QI interventions for people with diabetes is feasible to implement and highly acceptable. However, more research is needed to understand their effective components as well as the adoption of an equity-oriented approach in conducting primary studies. Moreover, a wider variety of socio-economic characteristics such as social capital, place of residence, occupation, education, and religion should be addressed.

Cohort profile: the Italian Network of Longitudinal Metropolitan Studies (IN-LiMeS), a multicentre cohort for socioeconomic inequalities in health monitoring.

PURPOSE: The Italian Network of Longitudinal Metropolitan Studies (IN-LiMeS) is a system of integrated data on health outcomes, demographic and socioeconomic information, and represents a powerful tool to study health inequalities. PARTICIPANTS: IN-LiMeS is a multicentre and multipurpose pool of metropolitan population cohorts enrolled in nine Italian cities: Turin, Venice, Reggio Emilia, Modena, Bologna, Florence, Leghorn, Prato and Rome. Data come from record linkage of municipal population registries, the 2001 population census, mortality registers and hospital discharge archives. Depending on the source of enrolment, cohorts can be closed or open. The census-based closed cohort design includes subjects resident in any of the nine cities at the 2001 census day; 4 466 655 individuals were enrolled in 2001 in the nine closed cohorts. The open cohort design includes subjects resident in 2001 or subsequently registered by birth or immigration until the latest available follow-up (currently 31 December 2013). The open cohort design is available for Turin, Venice, Reggio Emilia, Modena, Bologna, Prato and Rome. Detailed socioeconomic data are available for subjects enrolled in the census-based cohorts; information on demographic characteristics, education and citizenship is available from population registries. FINDINGS TO DATE: The first IN-LiMeS application was the study of differentials in mortality between immigrants and Italians. Either using a closed cohort design (nine cities) or an open one (Turin and Reggio Emilia), individuals from high migration pressure countries generally showed a lower mortality risk. However, a certain heterogeneity between the nine cities was noted, especially among men, and an excess mortality risk was reported for some macroareas of origin and specific causes of death. FUTURE PLANS: We are currently working on the linkage of the 2011 population census data, the expansion of geographical coverage and the implementation of the open design in all the participating cohorts.

Access to percutaneous transluminal coronary angioplasty and 30-day mortality in patients with incident STEMI: Differentials by educational level and gender over 11 years.

BACKGROUND: Socioeconomic status and gender are associated with access to cardiac procedures and mortality after AMI, also in countries with universal health care systems. Our objective was to evaluate the association and trends of educational level or gender and the following outcomes: 1) access to PTCA; 2) 30-day mortality. METHODS: We conducted an observational study based on 14,013 subjects aged 35-74 years, residing in Rome in 2001, and hospitalised for incident STEMI within 2012 in the Lazio region. We estimated adjusted ORs of educational level or gender and: 1) PTCA within 2 days after hospitalisation, 2) 30-day mortality. We evaluated time trends of outcomes, and time trends of educational or gender differentials estimating ORs stratified by time period (two time periods between 2001 and 2012). We performed a hierarchical analysis to account for clustering of hospitals. RESULTS: Access to PTCA among patients with incident STEMI increased during the study period, while 30-day mortality was stable. We observed educational differentials in PTCA procedure only in the first time period, and gender differentials in both periods. Patterns for 30-day mortality were less marked, with educational differentials emerging only in the second period, and gender differentials only in the first one, with patients with low educational level and females being disadvantaged. CONCLUSIONS: Educational differentials in the access to PTCA disappeared in Lazio region over time, coherently with scientific literature, while gender differentials seem to persist. It may be important to assess the role of female gender in patients with STEMI, both from a social and a clinical point of view.

Education and Mortality in the Rome Longitudinal Study.

BACKGROUND: A large body of evidence supports an inverse association between socioeconomic status and mortality. We analysed data from a large cohort of residents in Rome followed-up between 2001 and 2012 to assess the relationship between individual education and mortality. We distinguished five causes of death and investigated the role of age, gender, and birthplace. METHODS: From the Municipal Register we enrolled residents of Rome on October 21st 2001 and collected information on educational level attained from the 2001 Census. We selected Italian citizens aged 30-74 years and followed-up their vital status until 2012 (n = 1,283,767), identifying the cause of death from the Regional Mortality Registry. We calculated hazard ratios (HRs) for overall and cause-specific mortality in relation to education. We used age, gender, and birthplace for adjusted or stratified analyses. We used the inverse probability weighting approach to account for right censoring due to emigration. RESULTS: We observed an inverse association between education (none vs. post-secondary+ level) and overall mortality (HRs(95%CIs): 2.1(1.98-2.17), males; 1.5(1.46-1.59), females) varying according to demographic characteristics. Cause-specific analysis also indicated an inverse association with education, in particular for respiratory, digestive or circulatory system related-mortality, and the youngest people seemed to be more vulnerable to low education. CONCLUSION: Our results confirm the inverse association between education and overall or cause-specific mortality and show differentials particularly marked among young people compared to the elderly. The findings provide further evidence from the Mediterranean area, and may contribute to national and cross-country comparisons in Europe to understand the mechanisms generating socioeconomic differentials especially during the current recession period.

[Socioeconomic position and appropriate antiplatelet therapy after percutaneous coronary intervention: a population-based cohort study in Rome (Lazio Region, Central Italy)]. / Posizione socioeconomica e aderenza alla terapia antiaggregante post angioplastica coronarica: uno studio epidemiologico a Roma.

OBJECTIVES: to evaluate the association between socioeconomic position (SEP) and adherence to appropriate antiplatelet therapy (AAT) after percutaneous coronary intervention (PCI) in the year following the discharge. DESIGN: according to scientific guidelines, AAT for PCI patients consists of Clopidogrel for a minimum of 1 month and ideally up to 12 months after discharge, and with Acetylsalicylic Acid (ASA) indefinitely. For each patient, drug claims over a 1-year period after discharge were retrieved from Regional Drug Dispense Registry. Drug use was measured with Proportion of Days Covered (PDC). PDC was computed dividing the total number of dispensed Defined Daily Dose by each patient's follow-up time. Dual antiplatelet therapy with PDC ≥75% and single therapy based on Clopidogrel with PDC ≥75% were considered as AAT. We used a composite area-based index of socioeconomic position by census block of residence built using the 2001 census of Rome, assuming 5 levels (from 1 =High SEP to 5 =Low SEP). SETTING AND PARTICIPANTS: study population of 5,901 patients resident in Rome, who underwent their first PCI during 2006-2007 were selected from the Hospital Information System. MAIN OUTCOME MEASURES: proportions of patients treated with AAT by SEP was measured for the overall year and by semester. The association between SEP and adherence to AAT was estimated through logistic regression models adjusting for factors selected by a stepwise procedure (gender, age, comorbidities, discharged from cardiology or coronary care unit, new user of antiplatelet drugs). RESULTS: 76% of the study population were men, 96% were aged more than 44 years, and 63% belonged to medium-low SEP. In the 1-year follow-up, the proportion of patients adherent to appropriate antiplatelet therapy was 65%; SEP was associated with AAT (OR high vs. low SEP 1.26; 95%CI 1.05-1.51; p trend =0.002). CONCLUSIONS: during the year after discharge, adherence to AAT of PCI patients was unsatisfactory and it decreased overtime more in medium-low SEP patients than in high SEP patients. Strategies to improve adherence to AAT among patients who underwent PCI need to be identified taking into account the multifactorial nature of poor medication adherence, and in particular patients' socioeconomic position.

Changing pattern of drug abuse among patients entering treatment in Lazio, Italy, between 1996 and 2003: transition from heroin to cocaine use.

AIM: This study describes temporal changes of the pattern of substance abuse among drug users in treatment in Lazio, Italy. METHODS: We used individual data from the surveillance system of drug users of the Lazio region. We measured temporal changes in: the number of drug users in treatment, main and any substance of abuse, and mode of referral to treatment. RESULTS: Among new clients, the proportion of heroin use decreased from 78.2% in 1996 to 37.6% in 2003 (p < 0.0001), while cocaine use increased from 4.1% in 1996 to 30.1% in 2003 (p < 0.0001). In 2003, any use of cocaine was reported by 43.1% of new cases as compared to 38.9% taking heroin, 36.8% cannabis and 5.3% other substances, 41.9% using more than one substance. In 2003, 37.7% of new patients were referred to treatment by the police as compared to 10.4% in 1996. CONCLUSIONS: Heroin use has been replaced by cocaine among people coming to treatment centres for the first time. The main mode of access to treatment of new cocaine and cannabis users occurred through mandatory referral by the police. Routine surveillance systems of treatment demand are essential to monitor temporal trends of patterns of drug use in order to plan proper treatment strategies.

[Volume and health outcomes: an overview of systematic reviews]. / Volume di attività ed esito delle cure: revisione sistematica della letteratura.

BACKGROUND: Improving quality and effectiveness of health care is one of the priorities of health policies. Hospital or physician volume of activity may be a measurable variable with a relevant impact on effectiveness of health care. There are several studies and systematic reviews evaluating the association between volume and outcome of health care. The aim of this review is to identify: areas, clinical conditions or interventions (prevention, diagnostic, therapeutic, surgical or clinical) for which an association between volume and outcome has been investigated; those for which an association between volume and outcome has been proved METHODS: Overview of systematic reviews and Health Technology Assessment reports; search of MEDLINE, EMBASE, The Cochrane Library, Web sites of Health Technology Assessment, other HTA Agencies, National guideline Clearinghouse, National Health Care quality tools (1995-february 2005). For each studied area results are described separately for each review due to the heterogeneity of outcomes, volume thresholds and results reported. No metanalysis has been conducted. Completeness of reporting of the systematic reviews has been evaluated using the QUOROM statement. For each review we evaluated the number of studies included and the proportion of studies with statistically significant results (p < 0,05). As far as in-hospital mortality is concerned, the different areas have been classified in the following groups: Strong evidence ofpositive association: areas with > or =10 studies included in the reviews, and high prevalence (> or =50%) of positive studies (p <0. 05) in the majority of reviews. Weak evidence of association: areas with 5 to 9 studies included in the reviews and high prevalence (> or =50%) of positive studies (p <0.05) in the majority of reviews. Weak evidence of lack of association: areas with 5 to 9 studies included in the reviews and high prevalence (>50%) of not statistically significant studies (p >0.05) in the majority of reviews. No suficient evidence of association: areas with less than 5 studies included in the reviews. No evidence of association: areas with > or =10 studies included in the reviews, and high prevalence (>50%) of not statistically significant studies (p >0.05) in the majority of reviews. The same literature search was then applied to identify primary studies published in each considered area following the most recent systematic review published. RESULTS AND DISCUSSION: We identified 21 systematic reviews and included 11 of them analysing 46 different areas. The majority of studies evaluate the effect of specific surgical procedures; the main outcomes considered are hospital mortality and 5 year survival for cancers. Considering in-hospital mortalilty as outcome, in 11 areas there is strong evidence ofassociation between volume of activity and outcome: abdominalaortic aneurysm (unruptured), percutaneous transluminal coronary angioplasty knee arthroplasty coronary artery bypass, surgery for oesophageal and pancreatic cancer, surgery for prostate cancer, colecistectomy, carotid endarterectomy, myocardial infarction, neonatal intensive care. It is never possible however to identify a unique volume threshold. For some of these areas, particularly coronary angioplasty and coronary artery bypass, there are many new studies published following the last systematic review; some specific aspects are being investigated such as the role of temporal changes in the association, the effect of different risk adjustment procedures and the separate role of physician or hospital volume. In some cases, for example knee arthroplasty in-hospital mortality could be an inadequate outcome on which judging the strength of association, in fact, the few studies evaluating other outcomes such as complications provide inconsistent results. For a range of areas the evidence of association is weak: AIDS, appendicectomy, cardiac catheterization, surgery for breast, lung, stomach cancer, hernia repair, hip fracture, hysterectomy and injuries. As far as AIDS is concerned, the few number of studies found is probably due to the lack of studies published after the introduction of effective therapies. All the included studies show an evidence of association between volume and in-hospital mortality. In no case we found weak evidence of lack of association while we identified three conditions for which the number of studies included in the reviews together with the prevalence of non significant studies do suggest lack of association; these are abdominal aortic aneurysm (ruptured), hip arthroplasty and surgery for colorectal cancer. In the case of hip arthroplasty as well, inhospital mortality could be an inadequate outcome, but only one old study found a positive association with risk of complications. Eventually there is a group of areas (n=22) for which there is not enough evidence to draw conclusions about the association between volume and outcome due to a small number of studies. In some cases, such as transplants, this could be due to the low rate of events; in this case all the few published studies show positive results. There are some limitations which should be taken into account in the interpretation of these results: despite the overall good completeness of reporting of the included reviews, the majority of studies included in the reviews themselves are cross-sectional studies representing a very weak study design to evaluate causality of the investigated association. Moreover the methodology of risk adjustment applied is heterogenous among studies and it is difficult to know the extent to which this can affect the observed results. It is eventually necessary to consider the possible occurrence of publication bias which could lead to an overestimation of the positive effect of volume on health care outcomes attributable to the lack of publication of negative studies. CONCLUSIONS: In some areas the evidence seems strong enough to guide health care organizational choices, although it is not possible to identify well defined volume thresholds. In other areas, particularly for non surgical conditions, where there is not enough evidence, it seems necessary to conduct proper epidemiological studies. Also the evaluation of effectiveness of using volume as an instrument of health policy requires further research. Taking into account the rapid and continuing process of technology development, the definition of standard and prerequisite volumes of care should be specific of each temporal period and health care system. It is therefore a dynamic process requiring a continuous review of the available evidence. In the area of evidence based public health, the limited available evidence should not impair the choice of actions based on limited evidence, but rather it should lead to the application of thefew available evidence on one side and to the planning of proper research in the areas of lack of evidence.