Introduction
This section provides links to checklists to help you evaluate different types of study. If you are unsure of the study design, you can start by working through the questions in EBVM toolkit 4. However, it is important to be aware that not all published papers fit clearly into one study design, and you may need to start with a checklist that covers the type of study and adapt the questions accordingly.
If you would like to see examples of how to adapt and complete a checklist we have examples here Journal clubs – RCVS Knowledge
Synthesised evidence
These are studies which systematically review and critically evaluate already published literature.
Systematic reviews
These are comprehensive surveys of a topic in which all the primary studies of the evidence have been systematically identified, those providing the most relevant evidence have been selected and critically appraised and then graded and summarised according to explicit and reproducible methodologies.
Evidence Summary
An evidence summary, such as a knowledge summary or critically appraised topic, is a concise appraisal of the best available evidence on a defined clinical question. They should follow an explicit methodology to identify and critically.
Evidence-based guidelines
Guidelines can provide an accessible way for practitioners to access recommendations for the care of patients with specific conditions. However, if they are to provide a high level of evidence and a reliable basis for clinical decision making it is important that they are based on a systematic and critical evaluation of the available evidence.
Interventional studies
Interventional studies are those where the researcher controls the intervention (diagnostic test or treatment) that the animal is exposed to. The reliability of these types of studies can be increased by providing a suitable comparator or control to the intervention being assessed, randomisation of the participants between the trial and control arm of the study and blinding of participants and researchers to which participants received the intervention.
Controlled trials
These are a type of interventional study where the conditions are controlled by the researcher. They can include experimental laboratory studies or clinical trials.
Observational studies
Observational studies are those where the researcher examines the outcomes of an intervention within two groups without having any influence on which animals get the intervention.
Cross sectional studies
These are studies that describe the characteristics of sample groups of animals. Data is collected at one point in time and two groups are identified – usually animals with a specified disease and those without. The relationships within the groups to given parameters are then considered and typically expressed as an odds ratio. As the data is taken at one point in time direction of cause and effect cannot be established.
Case control studies
These are where animals which have a disease condition are identified and any causal or risk factors are compared to a control group (without the disease). Information regarding the exposure is historical. These studies start with groups that already have the outcome (e.g. diabetes) and it looks back to examine what might have been the exposure factors (e.g. obesity)
Cohort studies
These identify a group of animals and follow them over time to see how their exposures affect their outcomes compared to another group that were not exposed to that factor, either the general population or another cohort of animals.
Other types of study
Studies reporting on the accuracy of diagnostic tests
Diagnostic tests may take many forms, including tests run on biological samples, such as blood or urine; imaging studies, such as radiographs or ultrasound; histopathology; and even aspects of the clinical examination.
Qualitative studies
qualitative studies seek to understand the experiences of the human subjects involved. They may involve veterinary professionals or owners as participants. and may be used in studies that look at the delivery of veterinary care or the experience of caring for animals with certain conditions.
Narrative reviews
These provide an overview of a subject, providing useful background information. Their usefulness may be improved if they provide references to a range of appropriate sources, contains explicit discussion of the evidence on which it is based, and acknowledges areas of uncertainty and knowledge gaps.