Evaluating for students
Onder beoordelen valt eveneens het verwerken van data, waarvoor softwaretools op het Athena platform zoals Excel en SPSS en online programma’s van Google Drive zoals Formulieren en Spreadsheets, nuttig zijn.
An intervention study is experimental research in which the effect of an experimental intervention is investigated. A (randomised) controlled trial is an example of an intervention study. A clinical study is a type of intervention study whereby the efficacy and safety of a clinical intervention or drug are tested. Clinical studies about drug research are divided into 4 phases: phase 1 to phase 4 (see What is the difference between a phase 1, phase 2, phase 3 and phase 4 study?)
In a phase 1 study the molecule is introduced for the first time in humans after having been tested on animals. In this phase researchers are investigating the safety of the new product, amongst other things, how much of the drug can be given without causing serious side effects. The metabolisation is also studied. Healthy volunteers are usually used for this phase. The study is not usually randomised and there is no control group.
In a phase 2 study researchers are investigating the efficacy of the new product in different doses and administration frequencies. The research groups usually consist of about 20 people with a specific disorder. In this phase too, the participants are often not randomly distributed into an intervention and control group.
An extensive clinical study takes place in phase 3. At this stage larger groups of participants are involved and the efficacy and safety are further investigated. This usually occurs in the form of an RCT, in which participants are randomly divided into different study groups. The new treatment is compared to a standard treatment or placebo.
Phase 4 studies are only conducted if the drug has been officially registered and put on the market. In this phase, the occurrence of side effects and the effect of long-term use are monitored, amongst other things. Phase 4 studies are also called post-marketing surveillance studies. These are not RCTs.
Source: Van Driel M. Verklarende woordenlijst voor evidence-based medicine. 2nd revised printing Ghent: Minerva, 2003. Available online.
You can find MS Excel and SPSS software on the Athena platform. Google Drive has online Forms and Spreadsheets that can be useful.
Via the platform Athena you can use the software NVivo.
These two presentations help you to get started:
- Self-instruction by Sofie Verhaeghe, Ineke van Eechoud en Tina Vandecasteele (based on a presentation by Saskia Decuman) (in Dutch).
- NVivo workshop by Katrien Verleye (in Dutch).
Similar software are MaxQDA, ATLAS and Dedoose.
You can probably already deduce something about the reliability from the URL and the digital information certificate of a source/website.
| URL extension | Type of organisation | Example | Objectivity, reliability |
|---|---|---|---|
| .com | Commercial | http://www.dokteronline.com | ? |
| .net | Network | http://www.cancer.net | ? |
| .gov | Government (USA) | https://www.nlm.nih.gov | + |
| .gov(.be) | Government | https://www.ehealth.fgov.be | + |
| .edu | Educational (USA) | http://library.medicine.yale.edu | + |
| .org | International non-profit | https://nl.wikipedia.org/ | +/- |
| .be / .nl / … | Country code | https://www.kcgg.be | ? |
The use of language (e.g. correct, objective language), the proprietor (e.g. University Hospital) and the up-to-dateness will also give you additional insight into the reliability. In any case check whether you can verify the information provided in other reliable sources.
In a case-control study researchers are dealing with a group of people with a specific disease or outcome that needs investigating (Cases) and a group of people without these characteristics (Controls). The exposure to a possible risk factor is measured and compared in each of these groups. The relative risk of exposure is expressed as an Odds Ratio in a case-control study. Case-control studies are usually performed in etiological research. In the case of rare diseases or diseases that evolve over a long period, researchers can use this study set-up to look into the relationship between risk factors and the emergence of a disease. In a nested case-control study the Cases and Controls are recruited from the population of a cohort study. When, during the course of the study, sufficient patients with a specific disease (Cases) have been identified, people without the disease (Controls) are also searched for in the same cohort. Since some data from Cases and Controls are known (because of data collection in the cohort study), these can be checked for, thus reducing the chance of bias because of known disruptive variables in this set-up.
In a prospective cohort study people who may or may not have been exposed to a risk factor (such as harmful substances or a lifestyle factor) are followed up for a long period of time (usually years). The population being monitored must be free of the outcome being investigated at the beginning of the study, so that the incidence of the outcome can be calculated in the group with exposure and the group without exposure.
A cross-sectional study is a kind of observational study, in which data about risk factors and/or outcomes are collected at a specific time in a population.
Source: Van Driel M. Verklarende woordenlijst voor evidence-based medicine. 2nd revised printing Ghent: Minerva, 2003. Available online.
In a systematic review, you start with a (research) question, and conduct a search for original studies that can provide an answer to this question. The databases and methods of analysis used are referenced in the process. The results and background features of the individual studies that are found are explicitly evaluated and analysed. The standards laid down and described by The Cochrane Collaboration in the Cochrane Handbook for Systematic Reviews of Interventions are generally regarded as the gold standard for writing a systematic review. Organisations, for example The BEME Collaboration, use this methodology (for systematic reviews).
In a narrative review the author himself makes a selection of the studies to be included and there is not usually a (description of a) search strategy. As a result, the scientific value of a narrative review is limited.
Source: Van Driel M. Verklarende woordenlijst voor evidence-based medicine. 2nd revised printing Ghent: Minerva, 2003. Available online.
A meta-analysis is a systematic review in which the results of a number of comparable clinical studies are pooled and recalculated. This enables the researcher to make a more reliable claim about the effect of an intervention or treatment. Every meta-analysis is in principle preceded by a systematic review.
Source: Van Driel M. Verklarende woordenlijst voor evidence-based medicine. 2nd revised printing Ghent: Minerva, 2003. Available online.
You can assess the quality of systematic review using AMSTAR (Assessing the Methodological Quality of Systematic reviews).
If you would like more information or if you have any questions, please contact our information specialist Heidi Buysse or information assistant Muguet Koobasi.
Do you have a question related to your literature review or do you need help with searching, processing or publishing of your literature/data? Then please fill in our form to give us a clear view of your question and so that we can advise you efficiently. Alternatively, you could email us at kcgg@ugent.be.