Essai randomisé contrôléUn essai contrôlé randomisé (ECR), , essai randomisé contrôlé (ERC), essai comparatif randomisé (ECR) (de l'anglais randomized controlled trial ou RCT), essai comparatif aléatoire ou encore essai contrôlé aléatoire (ECA) est un type d'étude scientifique utilisé dans de multiples domaines (psychologie, soins infirmiers, éducation, agriculture, économie) et en particulier en médecine où il occupe un rôle prépondérant.
Essai cliniqueUn essai clinique, ou étude clinique, ou encore essai thérapeutique, est une étude scientifique réalisée en thérapeutique médicale humaine pour évaluer l'efficacité et la tolérance d'une méthode diagnostique ou d'un traitement. L'objectif d'un essai n'est pas d'apporter un bénéfice thérapeutique au volontaire. Le Comité international des rédacteurs de revue médicales en donne la définition suivante : . Ces études sont souvent effectuées après des études expérimentales non-cliniques (sur des modèles animaux ou cellulaires) pour confirmer leur pertinence et leur sécurité.
Random assignmentRandom assignment or random placement is an experimental technique for assigning human participants or animal subjects to different groups in an experiment (e.g., a treatment group versus a control group) using randomization, such as by a chance procedure (e.g., flipping a coin) or a random number generator. This ensures that each participant or subject has an equal chance of being placed in any group. Random assignment of participants helps to ensure that any differences between and within the groups are not systematic at the outset of the experiment.
Health care qualityHealth care quality is a level of value provided by any health care resource, as determined by some measurement. As with quality in other fields, it is an assessment of whether something is good enough and whether it is suitable for its purpose. The goal of health care is to provide medical resources of high quality to all who need them; that is, to ensure good quality of life, cure illnesses when possible, to extend life expectancy, and so on.
Ingérence humanitaireEn politique internationale, l'idée d'ingérence humanitaire est apparue durant la guerre du Biafra (1967-1970). Le conflit a entraîné une famine, largement couverte par les médias occidentaux mais totalement ignorée par les chefs d'État et de gouvernement au nom de la neutralité et de la non-ingérence. Cette situation a entraîné la création d'ONG comme Médecins sans frontières qui défendent l'idée que certaines situations sanitaires exceptionnelles peuvent justifier à titre extraordinaire la remise en cause de la souveraineté des États.
Placebo-controlled studyPlacebo-controlled studies are a way of testing a medical therapy in which, in addition to a group of subjects that receives the treatment to be evaluated, a separate control group receives a sham "placebo" treatment which is specifically designed to have no real effect. Placebos are most commonly used in blinded trials, where subjects do not know whether they are receiving real or placebo treatment. Often, there is also a further "natural history" group that does not receive any treatment at all.
Randomized experimentIn science, randomized experiments are the experiments that allow the greatest reliability and validity of statistical estimates of treatment effects. Randomization-based inference is especially important in experimental design and in survey sampling. In the statistical theory of design of experiments, randomization involves randomly allocating the experimental units across the treatment groups. For example, if an experiment compares a new drug against a standard drug, then the patients should be allocated to either the new drug or to the standard drug control using randomization.
Bronchopneumopathie chronique obstructiveLa , abrégée BPCO, est un groupe de maladies chroniques systémiques respiratoires, affectant souvent les bronches puis les poumons. Au Canada, la maladie est aussi appelée (MPOC). Sa prévalence est difficile à estimer à cause du sous-diagnostic, mais elle constitue la troisième cause de décès dans le monde avec de décès en 2019, touchant pour 80 % des pays peu ou moyennement développés. En France, cette pathologie aurait fortement augmenté depuis quelques décennies (probablement pour partie en lien avec le vieillissement de la population, le tabagisme et la pollution de l'air).
Treatment and control groupsIn the design of experiments, hypotheses are applied to experimental units in a treatment group. In comparative experiments, members of a control group receive a standard treatment, a placebo, or no treatment at all. There may be more than one treatment group, more than one control group, or both. A placebo control group can be used to support a double-blind study, in which some subjects are given an ineffective treatment (in medical studies typically a sugar pill) to minimize differences in the experiences of subjects in the different groups; this is done in a way that ensures no participant in the experiment (subject or experimenter) knows to which group each subject belongs.
Hierarchy of evidenceA hierarchy of evidence, comprising levels of evidence (LOEs), that is, evidence levels (ELs), is a heuristic used to rank the relative strength of results obtained from experimental research, especially medical research. There is broad agreement on the relative strength of large-scale, epidemiological studies. More than 80 different hierarchies have been proposed for assessing medical evidence. The design of the study (such as a case report for an individual patient or a blinded randomized controlled trial) and the endpoints measured (such as survival or quality of life) affect the strength of the evidence.
