[Evaluation of the effects of a complex intervention]. / Évaluation des effets d'une intervention complexe.

Appraising the effects of a complex intervention is one step in a more broadly based research process, from the construction or modelling of the intervention to its actual deployment. It consists in measuring the effectiveness or impact of the intervention, i.e. analyzing its capacity to produce change. The aim of this article is to obtain unbiased measurement of the average effects of an intervention, based on a panel of predetermined parameters and on the assumption of a causal link between the intervention and the measured result. This article is consequently devoted to evaluation of the effects of a complex intervention and focuses on the methodological challenges of its three key stages : 1) modelling of the intervention and feasibility analysis, essential prerequisites ; 2) the choice of study design and of the effects to be measured, that is to say the methodological premises ; and 3) process analysis, carried out in parallel with the evaluation of effects, leading to an indispensable appraisal of the intervention implementation and of the context into which it is integrated. The article is illustrated by five intervention impact assessment projects. A specific objective when evaluating the effects of a complex intervention consists in (a) moving away from a simple search for causality involving the intervention and its effects and (b) toward understanding of the effectiveness mechanisms, once again taking into account the context and the actual conditions of implementation. The challenge is to embrace rather than limit the complexity of the intervention, this being an essential prerequisite for its successful deployment and eventual generalization.

[Decision-making process and evaluation of public health interventions]. / Démarche décisionnelle et évaluation des interventions de santé publique.

OBJECTIVE: We have designed a methodological framework for experts involved in the support of decision-making in public health interventions. METHODS: The methodological framework consists of four elements: 1) A series of nine questions, formulated in non-technical terms, relevant to assessment of the usefulness of an intervention, at a given time in a given context; 2) Translation of these questions into concepts related to the evaluation of interventions (definition of the intervention, its target and objective, potential and actual effectiveness, safety, efficiency, and equity); 3) Logical organization of the information needed to address and answer the questions; and 4) An algorithm to translate the available information into recommendations on the real usefulness of the intervention in the context in which the questions were raised. RESULTS: Each step is illustrated by questions raised about road safety interventions, screening, blood transfusion and measures proposed during the COVID-19 pandemic. CONCLUSION: Decision-making can be facilitated if experts provide decision-makers with a formal summary of the strengths and weaknesses of existing knowledge, based on an analysis of all facets of an intervention's potential usefulness.

[Statistical and epidemiological methods used in biomedical research: implications for initial medical education]. / Méthodes biostatistiques et épidémiologiques employées pour la recherche biomédicale : implications pour la formation médicale initiale.

BACKGROUND: The main source of key medical information consists in original articles published in peer-reviewed biomedical journals. Reported studies use increasingly sophisticated statistical and epidemiological approaches that first require a solid understanding of core methods. However, such understanding is not widely shared among physicians. Our aim was to assess whether the basic statistical and epidemiological methods used in original articles published in general biomedical journals are taught during the first years of the medical curriculum in France. METHODS: We selected original articles published in The New England Journal of Medicine, The Lancet, and The Journal of the American Medical Association, over a period of six months in 2007 and in 2008. A standardized statistical content checklist was used to extract the necessary information in the "Abstract", "Methods", "Results", footnotes of tables, and legends of figures. The methods used in the selected articles were compared to the national program and the public health program of biostatistics and epidemiology taught during the first six years of medical school. RESULTS: The 237 analyzed original articles all used at least one statistical or epidemiological method. Descriptive statistics, confidence interval and Chi(2) or Fisher tests, methods used in more than 50% of articles, were repeatedly taught throughout the medicine curriculum. Measures of association, sample size, fit and Kaplan-Meier method, used in 40 to 50% of articles, were specifically taught during training sessions on critical reading methods. Cox model (41% of articles) and logistic regression (24% of articles) were never taught. The most widely used illustrations, contingency tables (92%) and flowcharts (48%), were not included in the national program. CONCLUSION: More teaching of the core methods underlying the understanding of sophisticated methods and illustrations should be included in the early medical curriculum so that physicians can read the scientific literature critically for their medical education.

Cross-cultural adaptation and validation of the knee and hip health-related quality of life (OAKHQoL) in a Moroccan Arabic-speaking population.

The aim of this study was to adapt the knee and hip osteoarthritis quality of life questionnaire (OAKHQoL) into Moroccan Arabic and to determine its psychometric properties. After translation, back-translation and pretesting, the translated version was submitted to an expert committee. The psychometric properties were tested on patients with hip or knee osteoarthritis. Internal consistency was tested using Cronbach's alpha coefficient (α), and the test-retest reliability using intraclass correlation coefficients (ICC). Construct validity was assessed by examining item-convergent and divergent validity and by comparing the average scores between age groups and walk perimeter groups. The study was conducted on 131 patients (115 with osteoarthritis of the knee and 16 with osteoarthritis of the hip). The "physical activities" (α = 0.93), "mental health" (α = 0.84) and "pain" (α = 0.88) dimensions of the Arabic version were internally reliable. The ICC were adequate to good; 0.83 for "physical activities", 0.65 for "mental health" and 0.70 for "pain" dimensions. The instrument demonstrated good construct validity; all items exceeded the 0.4 criterion for convergent validity, except items 13 and 41 and most of the correlations between items and their own scale were significantly higher than their correlations with other scales. A semantically equivalent translation has been developed with cultural adaptation of OAKHQoL. It is quite reliable and a valid measure of the effect of osteoarthritis on the quality of life on Moroccan patients.

Survey of European programmes for the epidemiological surveillance of congenital toxoplasmosis.

The objective of this investigation was to describe systems for the epidemiological surveillance of congenital toxoplasmosis implemented in European countries. In September 2004, a questionnaire, adapted from the evaluation criteria published by the United States Centers for Disease Control and Prevention, was sent to a panel of national correspondents in 35 countries in the European geographical area with knowledge of the epidemiological surveillance systems implemented in their countries. Where necessary, we updated the information until July 2007. Responses were received from 28 countries. Some 16 countries reported routine surveillance for toxoplasmosis. In 12 countries (Bulgaria, Cyprus, Czech Republic, England and Wales, Estonia, Ireland, Latvia, Lithuania, Malta, Poland, Scotland and Slovakia), surveillance was designed to detect only symptomatic toxoplasmosis, whether congenital or not. Four countries reported surveillance of congenital toxoplasmosis, on a regional basis in Italy and on a national basis in Denmark, France and Germany. In conclusion, epidemiological surveillance of congenital toxoplasmosis needs to be improved in order to determine the true burden of disease and to assess the effectiveness of and the need for existing prevention programmes.

[Consensus methods: review of original methods and their main alternatives used in public health]. / Méthodes de consensus: revue des méthodes originales et de leurs grandes variantes utilisées en santé publique.

BACKGROUND: Consensus-based studies are increasingly used as decision making methods, for they have lower production cost than other methods (observation, experimentation, modelling) and provide results more rapidly. The objective of this paper is to describe the principles and methods of the four main methods, Delphi, nominal group, consensus development conference and RAND/UCLA, their use as it appears in peer-reviewed publications and validation studies published in the healthcare literature. METHODS: A bibliographic search was performed in PubMed/Medline, Banque de données santé publique (BDSP), The Cochrane Library, Pascal and Francis. Keywords, headings and qualifiers corresponding to a list of terms and expressions related to the consensus methods were searched in the thesauri, and used in the literature search. A search with the same terms and expressions was performed on Internet using the website Google Scholar. RESULTS: All methods, precisely described in the literature, are based on common basic principles such as definition of subject, selection of experts, and direct or remote interaction processes. They sometimes use quantitative assessment for ranking items. Numerous variants of these methods have been described. Few validation studies have been implemented. Not implementing these basic principles and failing to describe the methods used to reach the consensus were both frequent reasons contributing to raise suspicion regarding the validity of consensus methods. CONCLUSION: When it is applied to a new domain with important consequences in terms of decision making, a consensus method should be first validated.

[The fate of the abstracts presented to the biannual meetings of the French National Society of Internal Medicine]. / Devenir des travaux publiés sous forme de résumés dans les actes des congrès semestriels de la Société nationale française de médecine interne.

PURPOSE: Medical meetings give the opportunity to present oral communications or posters to the attending participants. However, the peer-reviewed publication of a full article allows to reach a wide readership. KEY POINTS: The survey that was performed on the oral communications and posters presented at the 43rd meeting of the French National Society of Internal Medicine, December 2000, showed that amongst the 303 selected podium presentations and posters, only 82 (27%) were published during the five following years. Podium presentations were more likely to be published than posters (36% versus 22%). CONCLUSION: Many oral communications and posters that are presented in medical meeting are not followed by the publication of a peer-reviewed full article despite the modern means of communication. However, this issue is of paramount importance as beyond the legitimate personal satisfaction of a publication, the scientific and academic recognition are the ground of medical career achievement for many physicians.

Metabolic syndrome components in Indian migrants with type 2 diabetes. A matched comparative study.

OBJECTIVE: To study the metabolic syndrome (MS) in Indian subjects with type 2 diabetes (T2D) in comparing them with controls from the Indian community and from the general population. METHOD: An adapted definition of MS by the Third report of the National Cholesterol Education Program's Adult Treatment Panel III was used. We defined three groups matched for sex and age (+/-5 years). Non parametric tests for comparison of matched samples and conditional logistic regression were used. RESULTS: We selected 71 Indians with T2D (group 1) and two control groups with fasting blood glucose<6.1 mmol/L: 71 Indians (group 2) and 213 subjects from the general population (group 3). Patients were 24 to 76 years-old and each group contained 56% men. Globally, MS was identified in 77% of the group 1 when diabetes was taken into account. When diabetes was excluded there were 47% of MS in group 1, 18% in group 2 and 16% in group 3. The clusters of four factors (hypertension, large waist circumference, hypertriglyceridemia and Low HDL-C) were more common in Indians. The most frequent factors were hypertriglyceridemia and large waist circumference in Indians. Indians with T2D had a 5-fold higher risk of MS than the general population group, OR (95% CI): 4.93 (2.71 - 8.97); P<0.001. CONCLUSION: The high frequency of MS and of hypertriglyceridemia in Indians with T2D highlights the need for screening and management of MS in this population facing a high cardiovascular risk.

Factors affecting both peripheral blood progenitor cell mobilization and hematopoietic recovery following autologous blood progenitor cell transplantation in multiple myeloma patients: a monocentric study.

The aim of the study was to analyze the factors influencing peripheral blood progenitor cell (PBPC) collection after high-dose cyclophosphamide (HDCYC) (7 g/m2) and hematopoietic recovery after autologous transplantation of HDCYC-mobilized PBPC (ABPCT) in 116 patients with aggressive multiple myeloma (MM). Following HDCYC 74 patients received hematopoietic growth factors (HGF), either G-CSF (n = 19) or GM-CSF (n = 55). All the patients were subsequently planned to undergo ABPCT. PBPC collection was possible for 106 patients. The most important prognostic factor for collection of more than 25 x 10(4) CFU-GM cells/kg and 2 x 10(6) CD34+ cells/kg was the use of HGF (P = 0.002 and 0.009, respectively). Previous use of an alkylating agent, response to treatment before HDCYC, and interval between diagnosis and HDCYC were also significant factors (P = 0.004, 0.025 and 0.001, respectively). The number of CFU-GM cells infused was the most important parameter for rapid and complete hematological recovery after ABPCT (P < 0.0001). Thus the use of HGF post-HDCYC is the major factor which, associated with reduced time between diagnosis and HDCYC and the use of an alkylating agent, could increase the numbers of hematopoietic progenitors collected, and subsequently improve hematopoietic recovery following ABPCT in MM patients.

Fatal farm injuries among young children.

Death certificate data concerning farm-related injury deaths among children 0 to 9 years of age in Wisconsin and Illinois for the period of 1979 to 1985 were reviewed. Average annual farm-related injury death rates were 3.2 per 100,000 rural children in Wisconsin (62 deaths) and 1.5 per 100,000 in Illinois (32 deaths). Rates were three times higher among boys than girls. The occurrence of two harvest-related peaks and the absence of fatality in children less than 1 year of age suggest that presence of children on the farm when supervision is diminished is a key factor in farm-related fatalities. Moving machinery (tractors, wagons, and trucks) was the source of injury in approximately 55% of all deaths. Drowning accounted for 15% of all farm-related deaths. Two fatalities related to gravity box wagons could have easily been prevented with simple safety devices. These findings suggest a need for developing environmental interventions in farms. This will require the allocation of more resources to farm safety programs and a revision of current farm safety legislation.

Clinical prediction of lower limb deep vein thrombosis in symptomatic hospitalized patients.

We evaluated two clinical scores for the prediction of deep venous thrombosis (DVT) in hospitalized patients (Wells' and Kahn's). We included 273 patients referred to the vascular exploration unit for the suspicion of DVT. A clinical questionnaire was tilled in by the practitioner and the scores were calculated from this form. 66 of the 273 patients had a DVT. When Wells' score was 3, a DVT was found by duplex echography in 51% patients; when the score was 0, a DVT was found in 9%. Kahn's score was not adapted to this population. We then developed a new simple score (cancer, palsy or plaster immobilization, warmth, superficial venous dilation, unilateral pitting edema, other diagnosis). A DVT was found in 76% patients with a score of 3 and in 11% in those with a score of 0. We therefore propose a 6-item score whose main advantages are simplicity and usefulness in routine practice.

Study of civilian victims of terrorist attacks (France 1982-1987).

The medical and psychological consequences of terrorism were assessed through an epidemiologic survey of 254 survivors of terrorist attacks (TA) that occurred in public places in France between 1982 and 1987 (20 bombings and 1 machine-gun attack). Physical lesions were typical of bombings (blast syndrome, burn, coma), but amputations were rare. Post-traumatic stress disorder (PTSD) was present in 10.5% of uninjured victims, 8.3% of moderately injured and 30.7% of severely injured ones. Major depression was found in 13.3% of all victims, with no difference according to the level of the injury. Prevalence rates were not different in males and females, nor did they vary with age of the victim. The prevalence of PTSD was not associated with the delay between TA and questionnaire completion. These findings suggest the need for including psychiatric assistance in the initial care of TA victims, especially severely injured ones.

Measuring the impact of trauma care on survival: rates of preventable death, effectiveness, and efficacy.

This paper focuses on the appropriateness of outcome measures to evaluate trauma care. The preventable death rate (PDR), based on the study of deceased patients only, has been the traditional measure of the impact of trauma care on improving the survival of patients with severe trauma. Another measure frequently used in other ares of evaluation research is the effectiveness rate--i.e. the survival rate in the total population of severe trauma patients. Because both the PDR and the effectiveness rate vary with the proportion of patients who would die even under conditions of optimal care, these two measures can be misleading. We illustrate their inadequacy by using published data on the impact of regionalization of trauma care. We propose the use of a third outcome measure of the impact of trauma care on survival, the efficacy rate--i.e. the survival rate among severe trauma patients with a potential for survival. Evaluation of trauma care should also measure outcomes other than survival and need not be restricted to patients with the most severe trauma. Evaluation of trauma care therefore requires outcome measures, such as the efficacy rate, which are based on the population at risk of manifesting the outcome of interest.

Disability and handicap 5 years after a head injury: a population-based study.

A population-based cohort of 407 head trauma patients has been studied since 1986 to estimate the prevalence of long-term disabilities and handicaps by means of a structured questionnaire. Five years later, 6-1 patients were deceased and 36 were lost to follow-up. Prevalence of subjective and behavioral complaints was high whatever the initial head trauma severity. Lethality in severe head injuries was 56%, and half of the survivors remained disabled. In minor and moderate head injured patients, most disabilities were related to extracranial injuries. Taking all disabilities into consideration, each year 24 per 100,000 patients of such a population are likely to suffer from at least one long-lasting disability, including 10 per 100,000 whose disabilities are due to extracranial injuries. Head injuries induce long-lasting handicap in 9 per 100,000 habitants which is severe in 2 per 100,000. These figures point to the need of reinforcing preventive actions and long-term care of these patients.

Injuries in a problematic socioeconomic context: a population-based study in Réunion, Indian Ocean, 1993-1994. GEAR. Groupement d'Etude sur les Accidents à la Réunion.

BACKGROUND: This study was designed to estimate the incidence and describe the characteristics of injuries during a one-year period in the French island of Réunion, Indian Ocean, a defined geographic population with socioeconomic problems. METHODS: Cases were injuries from accidents (unintentional injuries), self-inflicted injuries (suicides and attempted suicides), or injuries purposely inflicted by other people, that resulted in hospital admission or death. Patients and injury characteristics were recorded prospectively, alternately every other week, in all emergency rooms on the island; all death certificates were studied. RESULTS: The overall annual incidence of injuries was 1578 per 100,000 residents. The three main causes of injury were (i) falls on the same level (23.6%), (ii) poisoning (23.0%) and (iii) traffic accidents (21.5%). Of the traffic accident cases, 44% were motorcyclists (mostly mopeds) and more than half of the cases were 15-25 years old. Suicides and attempted suicides accounted for 80.9% of poisonings, 35.5% of immediately fatal injuries, and 19.6% of non-fatal injuries. Homicides and assaults accounted for 8.3% of all injuries. The employment rate was lower for injured patients than in the total Réunion population (standardized ratio for males: 74; P < 0.001). Half of the injured hospitalized patients had an Injury Severity Score < 5 and 8 days after hospitalization, 83.5% of patients had returned home. CONCLUSION: Injury epidemiology may be affected by different demographic, socioeconomic, cultural and geographical factors. Targeted studies are therefore necessary to guide injury prevention measures.

The effect of the 1979 French seat-belt law on the nature and severity of injuries to front-seat occupants.

In a regional study of the effect of the 1979 French seat-belt law, the nature and severity of car occupants' injuries were recorded for all car crashes during the same 3-month period in 1976, 1977, 1978 (before the law), and in 1979 (after the law). A trend analysis of data from all 4 years showed a slight decrease in the total injury rate, and significant decreases in the frequency of hospital admissions, and of head, face, arm, and leg injuries. Moderate pelvic and leg injuries, and serious head injuries were also less than expected in 1979. There was also a significant increase in the frequency of thoraco-lumbar spine injuries and of serious cervical spine injuries, but the absolute increase in these injuries was less than the absolute decrease in other injuries. These changes are compatible with the biomechanical effects of increased seat belt use, and thus suggest a beneficial effect of the law.

Road accident statistics: discrepancies between police and hospital data in a French island.

In most developed countries, information on road crashes are routinely collected by the police. However, comparison of police records and hospital data underlines a deficit of the number of road accidents in the routine statistics. In La Réunion, a French overseas dependency, an epidemiological study of injuries leading to hospitalisation or deaths has been performed from June 1993 to June 1994. The comparison between hospital data and police records showed that only 37.3% of non-fatally traffic-injured in-patients were recorded by the police. Length of stay in hospital, physician in charge of the first aid, urban place of the crash, type of vehicle involved, day and time of the crash and blood alcohol concentration were significantly associated with the presence in the police file. Police overestimated the severity of the injuries. Police notified 100 deaths on the 115 counted by the study. In France, non-fatally traffic-injured should be followed 30 days to improve quality of police death records. A capture-recapture method was used to estimate the total number of injured people. The capture-recapture method consists in merging information from several sources of notification to determine the real number of cases in the population and the exhaustivity of each source. We estimated that 346 subjects were injured in one month whereas police data recorded only 87 and hospital data 137. This method seems interesting to use in routine after validation when unique personal identifiers are available.