Centre for Information Quality Management

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	Consistency. This is interpreted as meaning the extent to which records within a database follow the rules with regard to field assignments, field tags and other data elements, as well as indexing and editorial decisions.

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	Coverage/scope How well does the database cover its subject area(s)? Is it the "authoritative" file in its discipline? Are periodicals indexed cover to cover? If not, is the producer's policy on inclusions and exclusions clearly stated? Are there any serious gaps (including short- or long-term gaps caused by technical problems) or misinterpretations? Are temporary problems or changes in file content flagged in a log-on banner?

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	Error rate What data sources are used? How current and complete are they? Is there a prevalence of typographical errors, incomplete records or other dirty data? What percentage of errors occur in critical fields (e.g. company name, numeric)? What is the error rate per update? What percentage of records are received by the database producer on tape as opposed to being keyed or scanned in? What quality control procedures does the producer employ? Are faulty records identified and/or removed and corrected? Are corrections in the source material or print equivalent incorporated in the database? If so, how promptly? Is there a mechanism for users to tag faulty records and bring them to the attention of the database producer? Are searchers compensated for unusable information?

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	Output Can the user define custom formats? Can pages or portions of a document be printed selectively? Can search results be batch-printed and sent by mail, electronic mail, diskette or fax? Can print commands be bundled or stacked? Can search output be downloaded into spreadsheets or database management programs? Is downloading possible with the correct formatting (e.g. for tables)? Is there an auto-logoff option that will disconnect from the system at the end of a print or download session? Does the system support data compression? Error checking? What is the highest baud rate that the system supports? Are record aesthetically acceptable, e.g. not all in upper case? Are tables and graphic material included, or just referenced? If included, how are they formatted and presented? If not, are captions included?

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	Customer Support Is there a toll-free number for customer service? Is live, knowledgeable customer support available whenever the system itself is up? Can customer support be reached via electronic mail, and is it responsive in this fashion? What kind of training is available, both basic and advanced? Is training free or reasonably priced? Do training sessions include free post-session practice time? To what degree is training available outside the main urban centres? Is customer support available in countries other than that in which the system or database producer is located? Are there computer-based or video tutorials, or other forms of self-paced instruction? Is there a low-cost or after-hours practice file? Does the producer or online service support user advisory panels, etc? Is free time offered on a file being used for the first time? Is there a "free file of the month" policy? Are changes made to database without warning/documentation for users?

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	Accessibility Does the system require special software or dedicated hardware? Can the user sign up online, or must written contracts be negotiated first? Is the database accessible through gateways as well as directly? Does the system support full and variable proximity searching? Are there limits on word adjacency? Is there a mechanism for searching literals and stop words as parts of phrases? Are there built-in equivalences and on/off automatic pluralization? Can terms be plucked from an online thesaurus and used in a search without re-keying? Can a search strategy be saved and re-used in another database? Is there a multilingual thesaurus with an automatic synonym option? Within the database itself, how deeply and flexibly are the records indexed? What kind of subject indexing, if any, is used? Which data elements are searchable? If some are display-only, is this clearly documented? In full-text records does a "KWIC" display blow back to the current page rather than to the beginning of the record? [blow back is their phrase - I leave you to guess!] Is there a "locate" feature that will display the occurrence of any term - not just search terms - in an existing answer set? In there a well-maintained online thesaurus?

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	Timeliness How often is the file updated? How current is the material included in each update? Does one type of publication have priority over others? If so, is this documented? Are time-sensitive sources available in near-real-time? Does the load cycle vary from system to system(host to host or medium to medium), so that one version of a database is consistently more or less timely than another?

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	Integration Does the overall database structure resemble that of other files of the same type that are likely to be searched with it? Do field and output format tags match those used in comparable databases on the same system? Can multiple files be searched together? Does the system support duplicate detection and removal? Are there system-wide journal lists and other cross-database search aids? Have links been forged between bibliographic and full-text records in the same database and in different ones? Can one link from textual records to related information in external, perhaps multimedia sources? Can one search for a journal or other source by name, without knowing or specifying the database that carries it?

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	Documentation Is both print and online documentation timely, accurate and readable? Is it available free or at nominal cost? Is a print thesaurus available? Are there regular mailings of newsletters, search aids and other support material? Is this information practical and useful? Is documentation locally-resident (as opposed to online), well designed and easily searchable? Is online help available? Is it context-sensitive? Do log-on banners and other online pointers alert the user to database limits and useful features, as well as to temporary problems? At the source level, does database documentation outline editorial policies with regard to coverage dates, currency, inclusions and exclusions?

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	Value to Cost Ratio Do general system characteristics like speed and performance, pricing structures and display options support efficient, cost-effective searching? Is there at least one free or inexpensive default format? For documents, does this format include title and publication year? In hybrid files, does it include a full-text indicator? Is a KWIC display supported? Are display charges for various formats consistent with other databases? How well do these costs reflect the value of the data elements? How are user-defined formats priced relative to fixed formats that contain the same information? Does it cost about the same to print offline as it does to print online (assuming the connect charges associated with the latter will about equal the "per hit" cost differential between an online and a more expensive offline print)? Can search results be sorted or relevance ranked? Does the break key work while the system is processing a search, as well as during document display? Is there a charge for items included in the display command that have not yet been displayed? Is there a charge for partially displayed items? Are multiple hit charges imposed every time the same item is displayed in a search session, or do costs "top out" at a one-time charge for the fullest format in which the item was displayed? Is cost accounting available at any point during a search session, as well as at log-off? Are there up-front subscription fees, monthly maintenance costs or minimum usage charges?


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The Centre for Information Quality Management

A service of IAL, run on behalf of the UK eInformation Group (UKeiG) and CILIP: the Chartered Institute of Library and Information Professionals since 1993.

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Database Quality Criteria

One of the earliest article on database quality was by Reva Basch in the October 1990 Database Searcher: Measuring the Quality of the Data: Report on the Fourth Annual SCOUG Retreat.

Since then, numerous articles have appeared on the topic (see Readings and Links) and CIQM has put together a table of evaluation criteria.

SCOUG (the Southern California Online User Group) came up with ten headings or criteria by which databases should be judged; while I do not always agree with the way in which they have divided topics by these headings ("currency" under the heading "accuracy", for instance), they do make a useful guide. Their headings are (Click on the criteria for more detail):

After working in this area for some time, and analysing a range of approaches (Alexander and Tate (1999); Judith Conway (1998); Alison Cooke (2001)), CIQM developed a set of quality criteria specifically for Web resources. The table below offers sets of questions which users should ask themselves about the resource.

Quality Criteria	Evaluation Questions
Content	Audience? Audience groups? Purpose/ Motivation? Timeliness? Currency? Completeness? Accuracy of information and links? Are there external links/ should there be/are they appropriate/are they date-stamped? Dates of coverage (this could also go under relative value in final section)? Intrinsic value to your users? Is the information useful in this format? Does content require frequent updating? Language (either level or national or both) appropriate? Is depth and scope consistent throughout site? What value is added by the medium (if any)? Is there/should there be an archive? Is standard information (e.g. times of opening) always clear and in sight? Is any information repeated needlessly?
Authority	Coverage? Scope? Reputation? Refereed/Editorial control? Author given? Author details (education, experience, etc) given? Contact information? Expertise of author/owner/publisher? Bias? Stability? Reliability? Is the text organised in a natural, logical and pedagogic way? Is there outdated or superfluous information? Useful headings? Date produced/mounted/revised? Are sources cited/are they reputable? How often is it updated? Is this apparent? Links up-to-date and reliable? If the site is a gateway or a portal what authority is given to its links? Who evaluates these? Who annotates these? Evidence of quality control? Meta-information (e.g. abstract) and metadata (e.g. subject terms, publisher)?
Design	Good graphic design? Readable? Good use of suitable colour(s)? Graphics and art serve a function/appropriate? Icons clearly represent what is intended? Text grammatical, spelling OK? Does text stand alone for use in text-only mode? Good balance of text and graphics? Is attention paid to needs of disabled? Presentation appropriate for audience/audience group? Interface clear and uncluttered? Too much/too little multimedia? Information lost in complex design? Is white space well used to enhance readability? Are there annoying features such as flashing banners or animated icons? Are graphics labelled to identify them to non-graphical browsers? Does resource use medium appropriately (or would it be as good/better on paper)? What makes this resource useful in electronic format?
Organisation & Navigation	Ease of use? Is structure of site clear? Is the organisation logical? Signposting/Navigation OK? Consistent sense of context/ position/level? Searchable? Does it contain PDF files that are not searchable? Navigation elements, Buttons and Menu items clearly/usefully labelled?
Access & Use	Relative value compared with other resources on topic? Easily accessed? Speed of access? If popular, is there a mirror site? Help pages? Appropriate interactivity? Do pages take a long time to load? Are there annoying features which make it difficult to use or prevent some users from accessing it (e.g. frames, white type that cannot be printed, Java)? Is the site free? Is it always available? Everywhere?

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