Double data entry

Paper CRFs typed twice by two people: the blind second entry, the differences and how the data manager settles them against the paper.

Registries, post-authorisation and academic studies are often kept on paper CRFs that the site or the sponsor's team types into the portal. A typo then becomes data. Double data entry has each chosen paper form typed twice by two people, compares the two entries field by field and lets the data manager settle every difference against the paper.

The Double data entry page of the demo study: forms with differences wait for the data manager.

Who does what

• The project administrator and the data manager choose the forms entered twice and settle the differences.
• The data manager, the investigator and the project administrator type the second entry, but never of a form they saved themselves.
• The monitor sees the list of their sites, without changing it.

Choose the forms

At the bottom of the page, in Forms entered twice, tick the forms kept on paper and press Save. From then on every saved copy of these forms appears in the list and waits for its second entry. Tables, files, calculated fields and labels are not compared.

The first entry

The first entry is the usual data entry: the form is filled in and saved in the visit as always, with its checks and queries.

The second entry

1. On the Waiting for the second entry tab press Enter again next to the form. The button is shown only to someone who did not save the form.
2. The page shows an empty copy of the form. Type the paper form as it is and leave empty what is empty on the paper; the first entry is not shown.
3. Press Save the second entry. If both entries agree, the form goes to Both entries agree; otherwise the differences go to the data manager.

The second entry is kept as typed and does not change the form. The double data entry pages never show the first entry to the second operator; the form itself stays open in the visit as usual, so the study's procedure should ask the second operator to work from this page.

Settle the differences

On the Differences to settle tab press Settle. For each field that differs the page shows the first and the second value side by side. Look at the paper CRF and choose The first entry is right or The second entry is right, with a comment, then press Save the decisions. A difference left unchosen stays open.

Taking the second value corrects the form through the normal save: the new value passes the form's checks and is written to the audit trail with the reason "Double data entry: the value of the second entry, checked against the paper CRF". A locked form or a value that fails its checks is not changed: correct it in the form itself.

If the site changes a settled value later, the field is compared again and comes back to the data manager.

Audit trail

Every second entry (how many fields, how many differences), every decision (both values, the choice and the comment) and every change of the chosen forms is a record in the audit trail. In a demo study the data managers type two forms again every week, with a few typos and their decisions.