From p 8 of Embase Indexing Guide 2015
Disease subheadings may be used to modify any disease term, e.g. infection or myocardial infarction. They are assigned whenever applicable, as defined in their scope notes. Among the 14 disease subheadings, two are designated as key subheadings:
- Drug therapy: when this subheading is indexed, the drugs used to treat the indexed disease are also indexed with drug subheading drug therapy.
- Side effect: when this subheading is indexed, the drugs reporting the indexed side effect are also indexed with drug subheading adverse drug reaction.
Adverse effects are a key aspect of Embase indexing. This section describes how they are indexed in Embase.
When an adverse effect is reported for a drug, this is indexed as follows:
- The drug is modified by the drug subheading adverse drug reaction,
- The specific adverse effect(s) are modified by the disease subheading side effect
- In Embase.com only, this indexing is displayed as a triplet:
cimetidine * adverse drug reaction * constipation constipation * side effect * cimetidine
The following rules apply for the indexing of adverse effects:
- The adverse effect is always indexed, whether reported as severe or not. Indexing of an adverse effect as a major descriptor means that it is a main topic of the article. It does not imply that the effect is reported as severe.
- If a specific adverse effect is explicitly looked for but not found, it is still modified by the subheading adverse drug reaction, as an indication that the article contains information that the adverse effect was expected to occur but was not found.
Example: in an article discussing a drug X that is notorious for blood toxicity, it is stated that this effect was looked for but not found. The following terms are indexed:
drug X * adverse drug reaction blood toxicity * side effect
In Embase.com this is displayed as:
drug X * adverse drug reaction * blood toxicity * side effect * drug X
- All adverse effects in Embase are disease terms. If an adverse drug effect is reported that cannot be designated by a disease term, it is still indexed - but since Embase requires that a disease term is indexed as a side effect for every reported adverse drug reaction, in this case the disease term side effect is additionally indexed and modified by the disease subheading side effect, leading to a format as shown in this example:
risperidone* adverse drug reaction
weight gain
side effect*
- If an article only reports adverse effects in general for a specific drug (without mentioning any specific adverse effect), the disease term unspecified side effect is indexed (modified by the subheading side effect)
- If an author states that for a particular drug no adverse effects were found, the disease term absence of side effects is indexed (modified by the subheading side effect)
antiallergic agent * adverse drug reaction absence of side effects * side effects
In Embase.com this is displayed as:
antiallergic agent * adverse drug reaction * absence of side effects absence of side effects
* side effect * antiallergic agent
