Check this page before you design a large study. It saves you from meeting a ceiling at question 151.
Structure
Item | Limit |
Sections (visits) per eCRF | 100 |
Sub-sections (forms) per section | 80 |
Questions per sub-section | 150 |
Static content blocks per sub-section | 40 |
Section prefix or suffix | 25 characters |
Questions
Item | Limit |
Variable name | 100 characters; letters, digits, hyphen, underscore |
Text input answer | 2,000 characters |
Placeholder text | 50 characters |
Radio buttons | 50 options |
Checkbox | 50 options |
Dropdown | 500 options |
Number value, Max decimal | 0 to 40 |
Rating | First number 0 to 9, last number 1 to 10 |
Slider | Values 0 to 1,000; increment from 0.01 |
Header | 200 characters |
Instruction | 20,000 characters |
Logic
Item | Limit |
Conditions per question | 20 |
Data validations per question | 25 |
Validation message | 250 characters |
Calcul formula | 1,000 characters |
Calcul reading another Calcul | 50 levels |
Queries per question | No limit since version 5 |
Repeating data
Item | Limit |
Repeated measures, entries per subject | 50 (default 20) |
Blocks inside a repeated measure | 40 |
Table/Matrix | 20 columns × 20 rows |
Files
Item | Limit |
File upload question, eCRF | 5 files per answer |
File upload question, ePRO | 1 file per answer |
File size | 10 MB per file by default. Datacapt can raise it for a study on request |
Accepted types | Images (.jpeg .jpg .png), video (.avi .mkv .mov .mp4 .wmv), audio (.wav .mp3 .aac .flac .ogg and others), documents (.pdf .doc .docx .xls .xlsx .csv .txt .zip), DICOM (.dcm) |
Study Documents | 10 MB per file |
Reports
Item | Limit |
Variables per report table | 100 |
Charts per study | 25 |
What Datacapt does not do, and the workaround
You may look for | Status | Workaround |
Numbered eCRF versions and a compare view | Not available | Save a blank eCRF PDF, a template and an export at each change. See Change an eCRF after the study is Live |
Editing the eCRF while the study stays Live | Not available | Set the study to Suspended for the time of the edit |
Visit windows defined on the visit itself (Day 14 ± 3) | Not available | A Calculate Date / Time question for the target date, and a date validation on the visit date. See Calculation recipes |
Unscheduled visits added by the site | Not available | A repeated measure named "Unscheduled assessment" in a dedicated section |
Functions inside formulas (IF, ROUND, MIN, MAX) | Not available | Chain several Calcul questions, use Max decimal for rounding, and data validations for thresholds |
Lab reference ranges per site | Not available | Number questions for the lower and upper limit on the lab form, and validations that compare the result to them |
Import of eCRF answers from Excel or CSV | Not available in the interface | The Datacapt API writes eCRF answers. See Create a personal API key |
CDISC ODM import or export | Not available | JSON template files carry a design between instances. Exports come in Excel, CSV and PDF |
SAS or SPSS export format | Not available | Export CSV by Values, and build your labels from the Items Dictionary sheet |
A separate training or UAT instance | Not available | Draft status is the test environment. Go-live deletes test data |
Partial SDV plans (SDV on selected items) | Not available | Monitors apply SDV by question, form or visit. Describe the targeted scope in your monitoring plan |
Custom subject statuses per study | Not available | The platform list is fixed. See Participant statuses |