Relatos de casos são evidências pouco confiáveis

This is a Portuguese translation of the second in a series of 36 blogs explaining 36 Key Concepts we need to be able to understand to think critically about treatment claims. With thanks to Felipe Medauar and Cochrane Brazil for the translation.

This blog explains that claims about the effects of a treatment may be misleading if they are based on stories about how a treatment helped individual people, or if those stories attribute improvements to treatments that have not been assessed in systematic reviews of fair comparisons.

Reviews of fair comparisons should be systematic

This is the twenty-first blog in a series of 36 blogs explaining 36 key concepts we need to be able to understand to think critically about treatment claims.

Reviews that do not use systematic methods may result in biased or imprecise estimates of the effects of treatments because the selection of studies for inclusion may be biased or the methods may result in some studies not being found. In addition, the appraisal of some studies may be biased, or the synthesis of the results of the selected studies may be inadequate or inappropriate.

Consider all the relevant fair comparisons

This is the twentieth blog in a series of 36 blogs explaining 36 key concepts we need to be able to understand to think critically about treatment claims.

A single comparison of treatments rarely provides conclusive evidence and results are often available from other comparisons of the same treatments. These other comparisons may have different results or may help to provide more reliable and precise estimates of the effects of treatments.

Tratamentos podem causar danos

This is a Portuguese translation of the first in a series of 36 blogs explaining 36 Key Concepts we need to be able to understand to think critically about treatment claims. With thanks to Carlos Henrique dos Santos Oliveira and Cochrane Brazil for the translation. This blog explains that people often exaggerate the benefits of treatments and ignore or downplay potential harms. However, few effective treatments are 100% safe. Always consider the possibility that a treatment may have harmful effects.

Case-control and Cohort studies: A brief overview

Saul Crandon provides an overview of Case-control and Cohort studies: what are they, how are they different, and what are the pros and cons you need to consider in each study design.

Does Evidence-Based Medicine Imply Utilitarianism?

In this blog, Sasha Lawson-Frost explores what moral values underpin or justify the practice of Evidence-Based Medicine, specifically in response to a recent article which stated “the policy side of evidence-based medicine is basically a form of rule utilitarianism”.

Assessing associations in observational studies

In this blog, Leonardo provides 5 interpretations that you should consider when you read or hear about a reported association in observational studies.

All should be followed up

This is the nineteenth blog in a series of 36 blogs explaining 36 key concepts we need to be able to understand to think critically about treatment claims.

People in treatment comparisons who are not followed up to the end of the study may have worse outcomes than those who are followed up. For example, they may have dropped out because the treatment was not working or because of side effects. If those people are excluded, the findings of the study may be misleading.

The Delphi Technique

This blog provides a detailed overview of the Delphi Technique, a method of congregating expert opinion through a series of iterative questionnaires, with a goal of coming to a group consensus. It covers what it is, the process involved, pros and cons and when you would consider using it.