[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.

[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.

Burden of road traffic injuries related to delays in implementing safety belt laws in low- and lower-middle-income countries.

OBJECTIVE: Delayed implementation of effective road safety policies must be considered when quantifying the avoidable part of the fatal and nonfatal injuries burden. We sought to assess the avoidable part of disability-adjusted life years (DALYs) lost due to road traffic injuries related to delays in implementing road safety laws in low- and lower-middle-income countries. METHODS: We chose one country for each of the regions of the World Health Organization (WHO) and World Bank (WB) country income levels. We used freely available data sets (WHO, International Traffic Safety Data and Analysis Group, the WB). Delays in implementation were calculated until 2013, from the year mandatory use of safety belts by motor vehicle front seat occupants was first introduced worldwide. We used life expectancy tables and age groups as social values in the DALY calculation model. From the estimated total burden, avoidable DALYs were calculated using estimates of the effectiveness of seat belt laws on fatal and nonfatal injuries combined, as extracted from published international reviews of evidence. RESULTS: From the reference year 1972, implementation delays varied from 27 years (Uzbekistan) to 41 years in Bolivia (no seat belt law as of 2013). During delays, total absolute numbers of DALYs lost due to road traffic injuries reached 8,462,099 in Nigeria, 7,203,570 in Morocco, 4,695,500 in Uzbekistan, 3,866,391 in Cambodia, 3,253,359 in Bolivia, and 3,128,721 in Sri Lanka. Using effectiveness estimates ranging from 3 to 20% reduction, the avoidable burden of road traffic injuries for car occupants was highest in Uzbekistan (avoidable part from 1.2 to 10.4%) and in Morocco (avoidable part from 1.5 to 12.3%). In countries where users of public transport and pedestrians were the most affected by the burden, the avoidable parts ranged from 0.5 to 4.4% (Nigeria) and from 0.5 to 3.4% (Bolivia). Burden of road traffic injuries mostly affected motorcyclists in Sri Lanka and Cambodia where the avoidable parts were less than 2% in both countries. In all selected countries, burden of traffic injuries mostly affected men (about 80%) as well as young people (15-34 years). CONCLUSIONS: Despite limited data availability in low- and middle-income countries, the avoidable part of the burden related to delayed intervention is measurable. These results can be used to convince countries to avoid delaying the provision of better protection to road users.

To Screen or Not to Screen: Reconciling Individual and Population Perspectives on Screening.

Screening is the early detection of a latent disorder by a test to allow early intervention with the aim of improving prognosis. Individual and population perspectives on screening are perceived as opposing interests of patients and the population. In this article, we try to reconcile these perspectives. The individual perspective is based on the clinical experience of a better prognosis at early stages and patients with missed opportunities. In the population perspective, screening is based on a population-oriented, evidence-based model and addresses the acceptability and possible negative effects, including for people without the disorder. Known possible obstacles to a positive effect of screening include a short latent stage, lead time, overdiagnosis, lack of acceptability, poor performance of tests, and misclassification of outcome. Randomized trials of screening are challenging and need an adaptation of standards such as the Consolidated Standards of Reporting Trials (CONSORT). Simulating the effects of screening can allow the consideration of complex screening strategies and other options to help avoid biases related to treatment improvement and prevention success. Reconciling both perspectives is possible by considering that hypotheses underlying the former are prerequisites for the latter. From an evidence-based medicine and policy perspective, we suggest that recommending screening or prescribing a test is unethical if all possible obstacles are not documented by providing the best available evidence.

Thermal conductivity versus depth profiling of inhomogeneous materials using the hot disc technique.

Transient measurements of thermal conductivity are performed with hot disc sensors on samples having a thermal conductivity variation adjacent to the sample surface. A modified computational approach is introduced, which provides a method of connecting the time-variable to a corresponding depth-position. This allows highly approximate-yet reproducible-estimations of the thermal conductivity vs. depth. Tests are made on samples incorporating different degrees of sharp structural defects at a certain depth position inside a sample. The proposed methodology opens up new possibilities to perform non-destructive testing; for instance, verifying thermal conductivity homogeneity in a sample, or estimating the thickness of a deviating zone near the sample surface (such as a skin tumor), or testing for presence of other defects.

Low-dose computed tomography screening for lung cancer in populations highly exposed to tobacco: A systematic methodological appraisal of published randomised controlled trials.

Low-dose computed tomography (LDCT) screening recommendations for lung cancer are contradictory. The French National Authority for Health commissioned experts to carry a systematic review on the effectiveness, acceptability and safety of lung cancer screening with LDCT in subjects highly exposed to tobacco. We used MEDLINE and Embase databases (2003-2014) and identified 83 publications representing ten randomised control trials. Control arms and methodology varied considerably, precluding a full comparison and questioning reproducibility of the findings. From five trials reporting mortality results, only the National Lung Screening Trial found a significant decrease of disease-specific and all-cause mortality with LDCT screening compared to chest X-ray screening. None of the studies provided all information needed to document the risk-benefit balance. The lack of statistical power and the methodological heterogeneity of European trials question on the possibility of obtaining valid results separately or by pooling. We conclude, in regard to the lack of strong scientific evidence, that LDCT screening should not be recommended in subjects highly exposed to tobacco.

Comparing responsible and non-responsible drivers to assess determinants of road traffic collisions: time to standardise and revisit.

OBJECTIVES: In 1994, Robertson and Drummer formalised the responsibility analysis as an alternative to case-control studies in the study of road traffic crashes. Our objective was to assess whether published responsibility studies respected standards defining adequate case-control studies. SETTING: Using Web of Science, Scopus and Google Scholar, we identified responsibility studies indexed until October 2013, which cited Robertson and Drummer's paper. After reviewing titles, abstracts and reference lists, we selected original studies comparing responsible and non-responsible drivers, published in peer-reviewed journals or proceedings. DATA AND ANALYSIS: We applied a grid to judge the conformity of the responsibility assessment to the original definition, and whether methods addressing representativeness of selection, accuracy of measures of exposures, confounding variables, and power met standards defining adequate case-control studies. RESULTS: Of 205 titles, we identified 20 papers. Methods of responsibility assessment were the original in three papers. Variations across studies concerned the number of mitigating factors included, or the use of questionnaires rather than police data (n=3). The ratio responsible/non-responsible drivers varied from 0.90 to 5.31, due to major variations in sampling methods, threshold selection, and data completeness. Selection or measurement issues were discussed in 13 papers, but seldom addressed in the design. A comparison of confounding factors in responsible and non-responsible drivers was presented in five papers. CONCLUSIONS: Basic requirements of case-control studies are often not or not clearly met in responsibility studies. There is a need to revisit the method and to adapt existing publication standards to the way responsibility studies are reported.

Methodological issues and research recommendations for prognosis after mild traumatic brain injury: results of the International Collaboration on Mild Traumatic Brain Injury Prognosis.

The International Collaboration on Mild Traumatic Brain Injury (MTBI) Prognosis performed a comprehensive search and critical review of the literature from 2001 to 2012 to update the 2002 best-evidence synthesis conducted by the World Health Organization Collaborating Centre for Neurotrauma, Prevention, Management and Rehabilitation Task Force on the prognosis of MTBI. Of 299 relevant studies, 101 were accepted as scientifically admissible. The methodological quality of the research literature on MTBI prognosis has not improved since the 2002 Task Force report. There are still many methodological concerns and knowledge gaps in the literature. Here we report and make recommendations on how to avoid methodological flaws found in prognostic studies of MTBI. Additionally, we discuss issues of MTBI definition and identify topic areas in need of further research to advance the understanding of prognosis after MTBI. Priority research areas include but are not limited to the use of confirmatory designs, studies of measurement validity, focus on the elderly, attention to litigation/compensation issues, the development of validated clinical prediction rules, the use of MTBI populations other than hospital admissions, continued research on the effects of repeated concussions, longer follow-up times with more measurement periods in longitudinal studies, an assessment of the differences between adults and children, and an account for reverse causality and differential recall bias. Well-conducted studies in these areas will aid our understanding of MTBI prognosis and assist clinicians in educating and treating their patients with MTBI.

Introduction to the findings of the International Collaboration on Mild Traumatic Brain Injury Prognosis: what is a prognostic study?

Prognostic studies of mild traumatic brain injury (MTBI) can serve many purposes. First, they are used to describe paths and outcomes of patients with MTBI. Second, they provide information on which characteristics are associated with the occurrence of outcomes. Third, they provide insight into the causation of poor or favorable course of the disease. Finally, they can assess how differences in the probability of outcomes can help predict the course of patients. In this article, we summarize methodologic principles used by the International Collaboration on MTBI Prognosis to appraise the prognostic literature. Differentiating prognostic factors (causally linked with outcome), prognostic markers (associated but not causally), and predictors is important to guide interventions, public health policy, and research. Ideally, prognostic studies need a clear statement of the type of question (hypothesis-generating descriptive, exploration of possible prognostic variables, confirmatory modeling of prognosis); a cohort study design with standardized follow-up of a representative population of patients with MTBI; a standardized data collection using reliable and accurate tools to capture clinically, biologically, psychologically, or socially relevant variables and outcomes; and an analysis of data based on survival methods. Interpretation of prognostic studies should consider biases related to differential inclusion of nonrepresentative samples of patients, poor measurements of outcomes, and poor control for confounders. Transferring prognostic results into clinical practice should be based on estimates of the predictive performance of models and on a demonstration that patient outcomes can be improved by the use of prediction rules.

[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.

Availability and quality of prehospital care on pakistani interurban roads.

Interurban road crashes often result in severe Road Traffic Injuries (RTIs). Prehospital emergency care on interurban roads was rarely evaluated in the low- and middle-income countries. The study highlighted the availability and quality of prehospital care facilities on interurban roads in Pakistan, a low-income country. The study setting was a 592-km-long National highway in the province of Sindh, Pakistan. Using the questionnaires adapted from the World Health Organization prehospital care guidelines [Sasser et al., 2005], managers and ambulance staff at the stations along highways were interviewed regarding the process of care, supplies in ambulances, and their experience of trauma care. Ambulance stations were either managed by the police or the Edhi Foundation (EF), a philanthropic organization. All highway stations were managed by the EF; the median distance between highway stations was 38 km (Interquartile Range [IQR]=27-46). We visited 14 stations, ten on the highway section, and four in cities, including two managed by the police. Most highway stations (n=13) received one RTI call per day. Half of stations (n=5) were inside highway towns, usually near primary or secondary-level healthcare facilities. Travel time to the nearest tertiary healthcare facility ranged from 31 to 70 minutes (median=48 minutes; IQR=30-60). Other shortcomings noted for stations were not triaging RTI cases (86%), informing hospitals (64%), or recording response times (57%). All ambulances (n=12) had stretchers, but only 58% had oxygen cylinders. The median schooling of ambulance staff (n=13) was 8 years (IQR=3-10), and the median paramedic training was 3 days (IQR=2-3). Observed shortcomings in prehospital care could be improved by public-private partnerships focusing on paramedic training, making available essential medical supplies, and linking ambulance stations with designated healthcare facilities for appropriate RTI triage.

[Anaphylaxis due to chicken meat]. / Choc anaphylactique à la viande de poulet.

Acute anaphylaxis due to chicken meat is very rare; only a few cases have been reported in the literature. We report the case of a 13-year-old girl, with a past history of allergic urticaria due to eggs, who presented immediately after ingestion of lightly grilled chicken meat with facial edema, dysphonia, acute dyspnoea and a feeling of suffocation. A few months later, the patient developed asthma in the vicinity of poultry and after contact with chicken feathers.

Hazard perception at high- and low-risk road sites: a pilot study of interurban roads in Pakistan and Cameroon.

OBJECTIVES: Interurban roads account for a significant proportion of traffic deaths in developing countries. In this pilot study, hazard perceptions of interurban road sites involved in ≥3 injury road traffic crashes were compared with those not involved in road traffic crashes on the same road sections. SETTINGS: Karachi-Hala (Pakistan) and Yaoundé-Douala (Cameroon) road sections were the main study settings. DATA: Videos of 26 high-risk sites and 26 low-risk sites from Karachi-Hala (Pakistan) and Yaoundé-Douala (Cameroon) roads, matched for the road section, were shown to 100 voluntary Pakistani drivers. Variations in perceived site hazardousness and preferred speed for each site pair were assessed. Analyses Factors associated with incorrect hazard perception of high-risk sites (perceived as safe) were assessed by multinomial logistic regression analyses. RESULTS: Drivers reported a higher hazard perception and a lower preferred speed for high-risk sites than for their matched low-risk sites in less than half of pairs (n=12, p≤0.02). Factors associated with increased likelihood of identifying a high-risk site as safe were as follows: flat road profile (adjusted OR=2.00, 95% CI 1.55 to 2.57), intersections (OR=1.96, 95% CI 1.43 to 2.68), irregular road surface (OR=3.56, 95% CI 2.68 to 4.71), nearby road obstacles (OR=2.57, 95% CI 1.96 to 3.39) and visible rain (OR=1.85, 95% CI 1.48 to 2.32). CONCLUSION: The methods used in this study might be useful in prioritising cost-effective improvements at high-risk sites.

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.

Emergency trauma care for severe injuries in a Moroccan region: conformance to French and World Health Organization standards.

In Morocco, injuries account for 11% of total burden of disease. Better organization of emergency care can improve the outcome of trauma patients. In Morocco, these services have been reorganized recently, but were never evaluated. The objective was to assess actual structure and processes of emergency trauma care in a Moroccan region. This comparative qualitative study was carried out in the region of Fez. The process and structure of contacting emergency care and prehospital emergency care were compared with the French 2002 standards. Emergency care at the University Teaching Hospital (UTH) was compared with World Health Organization 2005 Essential Trauma Care guidelines. Predefined care items were categorized as conforming to the standards or not. An emergency call center with a dedicated dial-up number has been established in the region since January 2007. Compared with the standards, this center was not protected by any legislation and was run by interns only. The center was underutilized during triage to help transportation of severe trauma patients. At the prehospital care level, only 3 out of 15 ambulances were equipped with resuscitation equipment and were used rarely. Only one of the ambulance staff out of three was trained in required skills. At the UTH, emergency care equipment and staff was nearly adequate. This study identified several opportunities for improvement in organizing trauma care in Fez particularly at emergency call center and ambulance service. A quality assurance program would be useful to further identifying improvements in this system.