Explaining the Importance of a Database Lock in Clinical Research

One of the most crucial aspects of research is clinical data management or CDM. Proper CDM will generate results with excellent quality, integrity, and reliability. Quality data is essential in order to support the final conclusions of a certain study.

The person responsible for this area of research is called a clinical data manager. This job position can be filled by a PI, a study coordinator, or a CRA - Clinical Research Associate. No matter who fills this position at your site, data management has to be done promptly and correctly in order to generate the best results. Aside from all the other reasons why data management is so important, it’s also what determines the future IP (investigational product) development.

On the subject of clinical data, the most important term is ‘’database lock’’. Here, we’ll explain what a database lock is and explain you the purpose of this practice. How efficient is database lock and what are the benefits from it?

What is a ‘’database lock’’?

Locking or closing a database is nowadays a crucial practice that is necessary in order to prevent unauthorized or unintentional changes after the final data entry, check-up, and analysis.

Apart from not being able to make any further changes, a database lock is also extremely important in randomized blinded trials in order to prove the integrity of the trial after the breaking of the blind. All data, from the beginning until the end of the clinical trial, is entered in the EDC system's eCRFs (electronic case report forms) and everything has to be resolved by the time of the database lock. The PI will have to sign all the books and all the data that’s entered in the database.

Since database lock is one of the most important phases in clinical data management, all clinical trials are required to have a structured and well-defined process of closing their database. Doing this is absolutely necessary in order to avoid the need to reopen and unlock the database after its closing.

Which are the most important steps to take before database lock?

The crucial thing to remember about database locks is planning! Planning ahead of time, and while data is still fresh and new can make preparations a lot easier. This is especially true for trials with large volumes of data. If you don’t have a carefully-planned clinical data management plan, things can get pretty messy as the time for database lock approaches.

Step 1: Make sure that all data have been received;

Step 2: All data have to be processed;

Step 3: Every single query is resolved;

Step 4: Any external data (such as laboratory) has been integrated with the main study database;

Step 5: Final quality audit check, to make sure that all data is present, correspondent, and accurate;

After the final check from the authorized person, the edit access of the study database will be removed and this removal date will be documented. This is the definitive point of the database lock!

Frequency of Database Locks

While in the past, database locks were done at the end of a study, nowadays, database locks are usually done quarterly. This is one of the most common complaints of site staff because it puts too much pressure on everyone involved in data collecting and management. While this may look like a downside of database locks, all functions of an EDC system - including database locks - are actually very beneficial for sponsors and people who invest in these studies. The reason why they do quarterly locks now is to evaluate and analyze the data, and then decide if the study is worth to continue. In some cases, the investigational drug will show to not be effective at all, while in others the drug might cause many serious adverse events. When this happens, the quarterly database lock allows sponsors to analyze the situation and decide if they want to continue the study and invest more resources or if they want to end it.

The option of having quarterly database locks was not technologically possible and available in the past because of the use of paper CRF. However, today, with the use of eCRF (electronic case report forms), sponsors have this option that can save unnecessary time and money.

How Beneficial are Database Locks?

Even though having a quarterly database lock might put some pressure on people responsible for this, it also pushes them to enter their data promptly and on time. Studies have shown that site staff that’s authorized to enter data, actually do this more regularly and more often when they know that they have a quarterly database lock. Doing this makes it easier to keep up with data entry so that when the time comes for closing the database, everything is cleaner and more organized.

Downsides of Database Locks

  • More pressure! As we’ve mentioned before, the frequency of database locks (quarterly) can put pressure on site staff. Knowing that everything is supposed to be clear and clean before the PI signs and the database is locked can be pretty hectic if it’s not done on time.
  • Answering queries! Another common downside of database locks is the answering of queries. Since everything in the database is interconnected, answering one query might rise 10 more, and then answering those 10 will result with 20 more. This can be frustrating, especially when it comes to computer-generated queries. Knowing that all queries have to be answered before a database lock, with both the sponsor and monitor controlling your database, can be pretty challenging, especially with repetitive queries which then trigger other queries.


Even though there are some small downsides of database locks, we can all agree that this is an important practice that can keep in line many site activities. Database locks promote prompt and regular data entry at the site, and it also gives sponsors the chance to assess the study sooner rather than later and decide if they think it’s worth it. In any case, good preparation for data lockdown is crucial for an easier finalization. Not preparing well will cause a last-minute chaos and confusion because it will be much harder to enter, sort out, and organize everything at once.


We aim educate everyone about clinical research while making it easier to find nearby trials.

Contact Us

19200 Von Karmen Avenue, Suite 600
Irvine, California, US

Patients Call: (855) 255-7049
Email: patients@trialjoin.com