Data HQ’s complete guide to database cleansing

What do we mean by “cleansing”?

The phrase “data cleansing” might conjure up images of ruthless deletion.

In reality, there are several facets to the data cleansing process, and removing contacts is just one of them. Here’s a fuller picture of the tasks involved:

• Standardising data entry and formatting
• Amending incomplete or incorrect data
• Appending new contacts’ information
• Deduplicating contacts
• Removing irrelevant or outdated contacts

The importance of cleansing your marketing data

The main purpose of data cleansing is to raise the overall quality of your database, so that it’s working harder for you and yielding better marketing results.

Doing so carries several top-level benefits:

1. A more complete, accurate view of your real customer base

All marketing data decays over time, whether it’s B2B or B2C. If your database is bloated with out-of-date contacts that you have no realistic chance of converting, your engagement data will be distorted and you’ll get an inaccurate view of campaign performance.

If you have 10,000 contacts but only 3,000 are relevant and current, you don’t want to base any future marketing decisions on how the unengaged 7,000 are behaving. You’re better off without them, and should be concentrating on your active customers and engaged leads.

By cleansing your database, you sift out these outdated contacts and gain a much clearer idea of who your customers (or potential customers) are.

2. Better targeting, higher conversion rates, more revenue

Once you have a clearer view of your customers, you can start to create marketing materials that are far more targeted – with specific messages tailored to recipients’ circumstances, motivations and needs.

By researching and profiling your customers properly, you should soon see your conversion rates and revenue shoot up. Instead of taking a scattergun approach and sending out just one or two lots of broad messaging to multiple types of customers, you’re now taking careful aim at each segment of your target audience.

3. Improved ROI and saved costs

Communicating with a purer database of contacts means you’re saving time and budget by not wasting effort or resources trying to convert the unconvertable. And if you send out direct mail as well as email, you’ll also save on postage costs here, sending out collateral only to addresses in your email marketing database you know are valid.

This leaner setup should improve your ROI immediately and tee it up for continued improvement over time – meaning that you start to achieve more with less.

4. Positive brand perception

Your reputation means everything to your business, particularly in this online age of Google Reviews, Trustpilot and social media.

If you send communications out to an unclean mailing list, even with the best of intentions, you risk becoming a spam artist – especially if you’ve previously bought contacts from a questionable data provider. How do you know they’re relevant? Have any of these contacts submitted unsubscribe requests that you’ve not actioned?

By sending out only to contacts you know are relevant, the public perception of your brand should remain positive.

How often should you revisit database hygiene?

There’s no magic number as such, but the more often you cleanse your data, the better. It will largely depend on the nature of your business and the durations of your customer buying cycles.

What we will say is that it’s easier to maintain if you keep on top of it, and (most importantly) this should mean that your data remains mostly clean. In any case, six months is a good rule of thumb for any organisation.

Which leads us smoothly on to the next section – an important question...

Can you clean your own data?

You can perform some database cleansing tasks in-house, but certain parts of the process require expertise.

The basic, do-it-yourself tasks

• Manually fixing formatting and personalisation issues (e.g. uncapitalised names)
• Identifying duplicate contacts by email address or some other unique reference within the file
• Combining duplicate files once identified (“deduplication”/“deduping”) – which you can do by matching columns within a spreadsheet
• Training all present and future staff on one consistent method of data entry – which isn’t a cleansing task per se, but it does help to ensure good housekeeping and minimise needless inconsistencies

However, it must be noted that these actions do not constitute thorough or long-term fixes, and won’t truly purify your data. They’re just a few ways that you can tidy up on a basic level – or, to look at it another way, some good initial steps that you can take before you enlist the specialist help of a data solutions provider.

Also bear in mind that the above tasks, although somewhat ‘simple’, can be time-consuming to carry out yourself, especially if you haven’t done them before or are apprehensive – so even if you do have the in-house human resource, you should consider whether it is an effective use of their time. The most efficient course of action might be to outsource the entire process to a data specialist, who can give that extra care and attention to your database marketing.

When should you work with a data cleansing specialist?

To properly cleanse your database, you’ll need to first commission a data specialist to carry out an independent data quality audit, so that you know where you really stand.

This will provide a more in-depth and thorough review of your data quality, as well as highlight any accuracy issues, such as those resulting from the data’s age or from errors during data entry. The audit will also uncover missing information such as address or phone number details, and (if available) company size, sector and more.

Once the audit is complete, you can choose what your next step is. The ideal outcome would be that your database is fine on the whole and just needs more regular maintenance, but if you already have doubts about it, the chances are that there will be bigger issues. It might be that you want to fix these issues yourself (or learn how to), but implementing the necessary solutions could be so complex and/or time-consuming that you want the data specialist to carry out a huge cleanse for you.

Scenarios where you should outsource to a data specialist

• You don’t know what you’re doing
• You’ve not cleansed your database for a long time
• You’ve never cleansed it before
• You’re unsure of your data quality for whatever reason

Crucially, remember that cleansing isn’t only about tidying up what you have: it’s also about appending your existing files.

A data provider’s ‘universe of data’ guarantees a certain level of recency. So, in the case of crossover contacts, the provider’s information will likely be more up-to-date than yours, which means you will be able to salvage some outdated contacts rather than wiping them entirely (which is what would have to happen if you undertook the big cleanse yourself).

They can screen your data against a number of industry-standard suppression files to ensure that out-of-date data is removed. In some instances, they can even provide new addresses for existing customers who have moved without informing you – which can be an invaluable source of new data and a method of reactivating lapsed customers. Why wipe a contact if you can update them? And this is something you can’t achieve if you keep the cleansing task to yourself.

Any upstanding data provider will source their data ethically and continually refresh it, and if you work with them, your database will start to benefit from that.

What makes a truly reputable marketing data provider?Has GDPR changed data cleansing best practice?

If you sell purely B2B, GDPR has only impacted you slightly. The main point of the GDPR is that it protects people’s personal data.

You do need to get consent from sole traders and non-incorporated partnerships if you want to email them – but not from regular business/corporate contacts in your mailing list, whom you can contact without worry of falling foul.

If you’re B2C, on the other hand, you absolutely must follow the new regulations to the letter if you want to remain on the right side of the law.

Even if you are B2B-only, it’s good form to source all of your contacts ethically and responsibly – especially as this will directly influence the success of your campaigns. If you buy a poor-quality business mailing list full of irrelevant and uninterested businesspeople, where is that going to get you, ultimately?

If you know or suspect that you’ve bought data from questionable providers in the past, the wisest thing to do is get an external audit ASAP, certainly if you haven’t cleansed since that purchase.

Records should be telephone-screened by your data supplier at least once every 12 months, and TPS/CTPS-checked every month.

How to formulate your data cleansing strategy

Although you will have to seek external help at some point in your data cleansing journey, you can and should approach it in your own way.

The starting point is always to examine your database and see if you can spot any issues or trends for yourself. If you feel confident enough to make the smaller fixes yourself, and you have the time, go ahead.

Next, you should contact some data specialists about your needs. Ask each provider exactly what their audit process entails, because some will be more thorough than others, and some will have bigger and better universes of data at their disposal. Once you have a promising shortlist, it’s time to really do your homework:

• Check Google Reviews, Trustpilot, etc.
• Ask the provider to put you in touch with a past or current client who can give you a genuine testimonial off the cuff
• Check that the provider is accredited – at the very least registered with the ICO and a member of the DMA

Database cleansing isn’t just a one-off process to be completed and then forgotten about, so make sure your chosen provider is committed to serving you in the long term. Auditing your data quality and carrying out the cleansing tasks is one thing, but working with you to map out an internal process for data collection and usage is entirely another – that’s what will provide true value for you.

Read more about maintaining clean data with this complete guide to data quality.