Your list could have taken an age to build and create, or you may have spent a fortune buying in a list for multiple-use in your direct marketing campaigns. But it takes just an instant for a list to become out of date.

The quality of your mailing list plays a huge role in the success of your direct mail campaigns, so it's vitally important to make sure your list is always clean, accurate and up date.

Potential customers can be instantly switched off to your proposition if you've spelt their name or address incorrectly. Plus there are the potential cost implications of sending multiple mailers to the same address by mistake.

All users of direct marketing are facing more and more pressure from consumers and government to make sure mailings are as accurately targeted as possible, to help reduce wastage that's seen as environmentally damaging.

There are also legal requirements on you to keep your data up to date and respond to enquiries from people on your list if you are registered as a data controller under the Data Protection Act.

The problem is that data doesn't have an endless shelf life - it changes constantly and is out of date almost as fast as it's collected.

This is because a direct marketing list of people will always change, because people change. Their lifestyles, circumstances and careers can alter at any time.

In the UK 3,200,000 people move house every year - that's up to 7,000 people every day. Approximately 11% of addresses are mailed incorrectly each year. Plus the latest official figures show that there were 572,192 deaths registered in 2006 across the United Kingdom.

An increasing number of data and list cleansing services are now becoming available to help businesses meet the challenge of keeping their list in best possible condition. A good cleaning service should check your data in the following ways:

Mailing Preference Service screening
The Mailing Preference Service or MPS register, enables consumers to have their names and home addresses in the UK removed from lists used by the direct marketing industry. Unwanted direct mail is unpopular with consumers, damaging to the direct mail industry, and unnecessarily costly to your business.

Wastage in direct mail is also seen to be damaging to the environment, not just in the amounts of paper wasted in this way but also the energy cost used to transport mailers to recipient's homes.

Your list of business or consumer addresses should be checked against the Mailing Preference Service (MPS) no more than 90 days before the list is used. If you use your list on an ongoing basis, then you need to check against the MPS every quarter.

Gone-Away Screening
Gone away suppression draws upon regularly updated data for consumers and businesses that have changed location. Few of us remember to notify absolutely everyone we need to when we move house, so using a gone away suppression service can ensure that your marketing lists are as up date as they can be.

Bereavement Screening
There can be few other marketing errors so distressing for the recipients as sending a mailing to a person who has recently passeddata doesn't have an endless shelf life - it changes constantly and is out of date almost as fast as it's collected.

data doesn't have an endless shelf life - it changes constantly and is out of date almost as fast as it's collected.

away, Not only can it greatly upset their relatives, but it can also create additional work for them in having to inform you of your error. Using bereavement screening suppression services direct marketers can screen their data for any recently deceased people.

Baby Mailing Preference Service Screening
Although it is a specialist sector, if you are planning a consumer mailing to promote any product or service related to babies, then it has to have been cleaned against the Baby Mailing Preference Service (Baby MPS) file before use. The BMPS file gives bereaved parents the option to have baby/infant related mailings suppressed for 12 months.

Fax Preference Service
Sending a marketing fax to a list has declined a little in popularity recently, but it's still used by a large number of businesses. But because of abuse of fax marketing, it is absolutely essential that you check your list of fax numbers against the Fax Preference Service (FPS) list no more than 28 days before your broadcast. If you are faxing frequently, then check your list on a monthly cycle.

Telephone Preference Service Screening
Research from Selectabase shows that over 60% of UK households and more than 55% of businesses have registered telephone numbers with the Telephone Preference Service, in order to block unwanted sales calls. This means that around 3 out 5 unchecked sales or marketing phone calls to consumers or businesses will now be to a TPS or CTPS registered number.

Businesses using the telemarketing without checking numbers against the TPS and CTPS registers first are now more likely to call registered numbers than unregistered phone numbers. If reported, the caller could face legal action and even a £5000 fine, so businesses must always check phone numbers first before they make a call.

Both the TPS and CTPS registers are being constantly updated, so your list should be screened no more than 28 days before it is called. If you have a telesales team calling all the time, then you need to check your list against the TPS or CTPS at least monthly.

Deduplication
Deduping your database screens it for multiple entries for the same address. These multiple entries can be caused by data entry errors, multiple responses by prospects, or when lists are merged with each other. Sending more than one mailer to the same address not only costs more, but looks highly unprofessional as well.

As well as screening your lists against these suppression files, you should also respond promptly to a request from a customer to access their details. Under data protection legislation, all information held has to be provided within a maximum of 40 days from being asked in writing. If it is appropriate, you can charge a maximum fee of £10 to provide data, but many organisations waive the fee as part of their commitment to customer service.

Follow the guidelines above and you'll ensure your lists are as accurate as possible, helping you to reduce wastage, target more effectively, and improve your return on investment in direct marketing campaigns.

Steve Sellwood is from Selectabase, UK providers of data cleansing services to clean and improve your existing customer database. The Selectabase suite of affordable data cleansing services includes 1Check to identify individual TPS registered numbers online, and free Easycheck software to check, clean and profile your own lists from your own PC.

For more information look at www.selectabase.co.uk