Microdata markup with properties on multiple pages

Question

I'm creating a web page and currently I'm adding Microdata markup to the code. I’m using schema.org’s MusicGroup.

I have an index.html page from where I'd like to take the name and the image properties for this band:

<div class="container" itemscope itemtype="http://schema.org/MusicGroup">
    ...
    <a href="index.php"><img itemprop="image" src="img/logo.png" alt="logo" /></a>
    <p>We are <span itemprop="name">NAME OF THE BAND</span>.</p>
    ...
</div>

However on the about_us.html page there is a short description which I'd also like to use:

<div class="container" itemscope itemtype="http://schema.org/MusicGroup">
    ...
    <p itemprop="description">A description of the band.</p>
    ...
</div>

When I use the code like this, search enginges (understandably) treat them as two different MusicGroups:

MusicGroup 1:
Image: .../img/logo.png
Name: NAME OF THE BAND

MusicGroup 2:
Description: A description of the band.

How can I link these properties into one item?

Answer 1

Microdata’s name-value pairs are per webpage, not per website.

So on a website about a music group, it can be expected that each page contains an "own" MusicGroup item, which is, however, actually always about the same music group. But from the Microdata or schema.org perspective, these different items would not be semantically connected that way (consumers might guess this however, e.g. by comparing property values).

Microdata’s itemid attribute could be used to uniquely identify each item. But it is required that the used vocabulary supports "global identifiers for items" (itemid is used for some types on schema.org (e.g., in the example for MedicalScholarlyArticle), but it’s not clear to me if it’s really supported as required by Microdata for other types, like MusicGroup).

So in your case, you could:

• leave it as it is
• duplicate the information, so that each item has all relevant content (possibly using meta/link elements)
• move all information on one page (possibly using itemref)
• (if it should be allowed for general use with schema.org) use itemid to state that several items are actually about the same thing