Using MetaMetrics® Lexile Analyzer software, titles are measured based on word frequency (semantic difficulty) and sentence length (syntactic complexity); the resulting Lexile value is numeric, rated on a scale between 0 and 2000. Generally, the larger the Lexile measurement, the more complex the sentence structure—as well as the frequency with which difficult words are used.

Additionally, the same Lexile measurement scale can be applied to identify a patron's reading comprehension. A reader's Lexile level indicates that they are expected to have a 75% comprehension score for a title with the same Lexile measurement. For example, a reader who has a Lexile measurement of 840 should be able to comprehend at least 75% of a title that also has a Lexile measurement of 840.

Currently, there are more than 100,000 books and more than 70 million newspapers and magazines articles which have been Lexiled, including some online databases.

Of those 100,000, there are some that can not be properly measured, and are, therefore, given a Lexile code as opposed to a Lexile measurement.

For example, beginning reader materials often have one or two words per page and no discernible sentences; therefore, instead of scoring a 0 or a negative number, they are assigned a Lexile code of BR (beginning reader).

Poetry and screenplays often use unorthodox punctuation and unconventional paragraphs and line-breaks. These make it difficult for the Lexile Analyzer to determine where a sentence begins and ends. Therefore, these are assigned a code of NP (non-prose).

Reading Counts™, one of the major study programs, uses Lexiles for student interest levels. Many other programs, however, use Lexiles as their standardized method for measuring reading comprehension.

If you use Reading Counts™ and your vendor includes that information in your MARC records, the Lexile information particular to Reading Counts is kept in the 526 tag under subfield _b.

Reading Level is kept in subfield _c and the study program name “Reading Counts” is located in subfield _a. This information can also be found at the Scholastic website, where you can look up titles individually.

It is not recommended that you enter Reading Counts information unless your school or institution also owns the accompanying tests; patrons who see such information may mistakenly think that they can get Reading Counts credit for reading that title.

Depending on your vendor, the MARC records that you purchase along with your books may already contain Lexile information. If not, they may become available by simply changing your profile with the vendor or by paying an additional charge.

Lexile information is usually stored in the 521 tag with the _a as the Lexile measurement and _b as the indicator of the Lexile.

You can also get Lexile information manually by searching the Lexile Book Database website. The Lexile Book Database is updated regularly, so if you have an item which lacks a Lexile score and can not be located in the database, be sure to check back frequently. What isn't measured today may be measured tomorrow.

If you have the full text of an item that is not contained in the Lexile Book Database, you can use MetaMetrics® online Lexile Analyzer to score your item.

However, to help make these processes easier, COMPanion has created a Lexile utility for Alexandria that compares your titles to those contained within the Lexile Book Database. If Lexile measurements are found missing from your titles, they will be added to your data.

For more information about the Alexandria Lexile module, contact your COMPanion sales representative at (800)-347-6439.