Being a set of a specific type means that the members of the set have some characteristic in common, in addition to their similarity of name. A list is an SIA only if both criteria for inclusion of an item in the list are met. For example, every entry in a list of earthquakes might include the word "earthquake", but that alone does not mean that the list is an SIA. If earthquakes were assigned names similar to how tropical storms are named, then List of earthquakes named X could be a set index (if there were multiple earthquakes with the same name).
Fundamentally, a set index article is a type of list article. The criteria for creating, adding to, or deleting a set index article should be the same as for a stand-alone list. The style of a set index article should follow the style guidelines at Wikipedia:Stand-alone lists. A set index article can be tagged with {{Set index article}}. Notably, an SIA is not necessarily titled a "List": it could, for example, be titled as a partial disambiguation, e.g., Star (newspaper).
red links to help editors create articles on notable entries, and
references (to document the respective bases for inclusion of entries in the list).
Occasionally there is both a disambiguation page and a set-index article organized about the same term. If the disambiguation page bears the term as its title (as is the case with Signal Mountain), then the set index article can be named "List of XXXs named YYY"; the example of List of peaks named Signal is an example of this.
If the circumstances allow a choice between having the (bare or unqualified) term link to a set-index page or to the disambiguation page, that term usually should be assigned as the disambiguation page's title because the disambiguation page type accommodates the widest variety of uses. (Nevertheless, in the rare cases where the set index article is considered the primary topic, it may be named with that term (without further qualification), with the disambiguation page accordingly being titled "YYY (disambiguation)" per guideline on disambiguation page naming.)
A disambiguation page should not be reclassified as a set index article on the basis that its entries all happen to be instances of a single type, unless the page has metadata or extra information about its entries. As an example, Western State Hospital is, correctly, categorized as a disambiguation page even though each of the articles it links to is literally a hospital (rather than some other type of building – or legal entity, titled work, mental state, etc., ad infinitum).
How to tell whether the page could be a set index article
Refer to the relevant guidelines for further details.
Typical information
1.
The information given by a set index article will depend on the specific type of items listed. For example:
For mountains, that information may include latitude and longitude, height, range, and political subdivisions.
For ships it could include type of ship, country, various dates (commission/decommission, ordered, laid down, launched), and notable battles or events the ship is associated with.
For a common name shared by several plants, information could include geographic range, taxonomic family, flower color, or photos.
2.
Refer to the categories listed below (e.g. ) for examples of the types of information that may be appropriate.
3.
Link to the article or article section on the subject of each entry, if there is one, and to related articles, e.g. political subdivisions, battles, taxonomic families. E.g.,
Information need not be repeated if it is the same for all entries. There is no point in stating that ships are frigates or plants have white flowers if that is clearly true of all the entries.
5.
There should be enough information on each item to differentiate it from the other items.
6.
The information should have the potential to help a reader with a passing familiarity with an item to identify the one they are interested in. Such a reader might know that a ship served in World WarII, or that a plant grows near where they live, but will not know the ship's pennant number or the scientific name of the plant.
Long lists should be structured so that a reader can readily find the item they are interested in. Alphabetical sequence, subheadings, and sortable tables may be useful.
10.
The introduction to a list that contains every member of the group should identify the source(s) for the complete list, which may be online databases, gazetteers, etc. The results of a general web search are not adequate.
11.
List items do not require citations if they only give information provided by the source(s) cited in the introduction to the list. If an item gives more information, that should be backed up by citations.
Tagging and categorizing an article as a set index article
Place one of the following templates at the bottom of the page, using the most specific template available. If there is no specific template, you can, as {{Set index article}} explains, use the most generic template with certain sort keys to more specifically categorize articles; the template's page also explains that you can use it to place pages into child categories of .
A summary of related policies and guidelines is given below. Editors should ensure that any set index article is compatible with these policies and guidelines. Refer to the current versions of the policies and guidelines for details.
Common criteria are that every entry is notable, or the list is short and lists every member of the group. Lists in which no entry is notable are rarely appropriate.
