Answers to these and similar questions will help you develop appropriate deduping specifications to determine which records will be retained and which eliminated during tape processing.

Conversion Services & Sources of Data

Many special and technical libraries do not participate in any shared cataloging project. For these libraries various other conversion methods are available. Criteria for selecting a conversion vendor should also include data requirements and input standards. Many library service bureaus supply MARC Records. Typically, their service will match your library's holdings (shelflist) against a large MARC database. Where a match is found, the MARC record is extracted and added to your file. Other conversion services simply create an input file by keying data from your shelflist. Some optical scanning devices have been used effectively on library shelflist cards. The effectiveness of this technique will depend on the consistency of the font used to create your shelflist. The best time to select a conversion services vendor is after you have decided upon various database standards and formats. For additional sources of information on data conversion refer to the annotated bibliography.

Catalog Record Content

What fields are needed for each type of information in the database? You may choose not to use all fields that have been defined, you may choose to make certain optional fields required, and in some cases, you may add new fields identified during your analysis of existing files. Consider management information that will be required of the system before creating the database. For example, if you want to know how many Spanish language materials are in the collection, the record must contain a code identifying it as being in Spanish. Information in the MARC-fixed field may not automatically be included in the record unless your conversion specifications call for it.

Thesaurus Control

A thesaurus may be used with your database to ensure consistency in form of entry and to provide cross-references and search redirection during retrieval. Thesaurus construction can be a lengthy but rewarding process. The recommended technique is to load the thesaurus first, then load the database. All incoming bibliographic records can be validated against the authorized heading to provide consistency. Some common thesauri (Library of Congress Subject and Name Authorities, NASA, MESH, etc.) are available for purchase and may be used to create a local thesaurus. A locally-developed thesaurus, whether in manual or machine-readable form, may be converted into a format appropriate for loading into the IOLS. Whether purchased or locally developed, the thesaurus must closely match the data in your database. Records validated against the thesaurus may be rejected if there is no exact match between the field contents and the thesaurus entry. Exception processing can be defined to allow inconsistent records to enter the database and identify them for cleanup.

If your library does not have a thesaurus or authority file, you may choose to build one after loading the database. Various utility programs are available to assist with the processing. This approach extracts the actual contents of the field to be thesaurus controlled. The resulting file can be sorted and modified to provide a preliminary authority file. With the addition of relationships between terms, the file can evolve into a complete thesaurus.

Additional resources on thesaurus construction may be found in the bibliography.

Item Inventory

After deciding on the structure of your database, you should consider item conversion. One copy record should exist for each item held by the library. Consistent entry of holdings information in the MARC holdings field facilitates creation of copy records. The availability, accuracy, and currency of the copy-level information in the bibliographic record affect the length of time necessary to add copy-level information to the automated system.

Barcodes

The availability, accuracy, and currency of the copy-level information determine the options available in barcoding the collection. The item inventory function is frequently accomplished using machine-readable barcode labels. If you use barcodes, your conversion plan needs to consider the method of attaching barcode labels to items in the collection and the method of linking that barcode number with the correct catalog record. Labels may be attached on the inside or outside of library materials. Outside labels may be more convenient during a shelf inventory but the label is more vulnerable and should be covered with special tape for protection.

There are two common methods of linking a barcoded item with its catalog record. In the first method, a random label is attached to the item, the bibliographic database is searched for the matching record, and the system is informed of the barcode number used. This linking process may be accomplished by systematically working through the collection or "on-the-fly" at checkout.

In the second approach to barcoding, the barcode number is already linked to the bibliographic details. After catalog records are loaded into the database and item records based on holdings details are created, a file may be created from which "smart" barcodes are generated. Sheets of labels, in shelflist order, are used to match the label to the appropriate item on the shelf.

If you prefer not to use barcodes, another unique identifier (such as Call Number or traditional item accession number) can be used to associate copy and title details. The best inventory for your library will depend substantially on the validity of holdings details.

Other Files

After reaching decisions about your catalog and copy information, do not ignore borrower, vendor, subscription and acquisitions data. There are few standards to facilitate the transfer of existing borrower or vendor information into the IOLS. Explore other departments in your organization to find out whether there are existing machine-readable files that may be useful in creating your database. With the exception of the vendor file, most acquisitions information is not converted into the IOLS. Most libraries prefer to begin placing new orders using the IOLS but to continue receiving items under the old system until all outstanding orders have been reconciled.

Data Clean-Up

Because retrospective conversion from a variety of sources and variations in cataloging practices over time may introduce inconsistencies and contribute possible problems with data integrity, it is a rare bibliographic database which does not on occasion need cleanup of some sort. Editing and global change capabilities facilitate the database cleanup process, making it easy to correct many of the problems encountered. Depending on the extent of inconsistency in the data, more or less time may be needed to prepare the database for public use. Be realistic, though, and do not strive for perfection before implementing the online catalog. Even dirty, the new database is better than the card catalog with its limitations.

Conversion Documentation

Regardless of the conversion methods used, it is useful to develop a conversion policies and procedures manual. Such a document will be useful as a staff instructional tool and as a reference manual during and after the conversion process. It can also serve to establish, record, and enforce agreed upon standards.