rVAS

Design multi-condition VAS studies your way. Draw a line as you would on paper and export analysis-ready XLSX files. No ads, works offline, and data is stored on-device.

Bring your paper VAS workflow to iPad.

rVAS is a flexible Visual Analog Scale (VAS) app for research and surveys. It combines study setup, data collection, automatic scoring, and XLSX export in one place.

No more printing and carrying paper forms, measuring responses with a ruler, or manually entering results into Excel. On supported iPads, the VAS scale is calibrated to 10 cm. Participants can mark the scale with a finger, Apple Pencil, or compatible stylus, just as they would on paper.

Each response is automatically converted into a VAS value. Results from multiple participants, conditions, and rating items can be exported together in an analysis-ready XLSX file.

【Flexible study design】

• Add multiple conditions or stimuli
• Create multiple VAS rating items
• Set repetitions for each condition
• Create custom presentation-order patterns
• Generate randomized presentation orders
• Assign an order to each participant
• Customize condition names, item names, and anchor labels
• Save and reuse project settings

rVAS can be used for pain, comfort, fatigue, sensory experiences, psychological states, stimulus ratings, and other subjective evaluations.

【Presentation order preserved】

When conditions are randomized, rVAS records the order in which they were actually shown.

Exports include both the actual presentation order and a standardized condition order, making it easier to review data as collected and arrange conditions consistently for analysis.

VAS values can be exported with the condition, rating item, trial, repetition, presentation order, and response timestamp.

【A paper-like VAS response】

Instead of dragging a conventional slider, participants draw a line on the scale. rVAS keeps the familiar paper-based response method while automating position measurement, value calculation, and data recording.

Studies comparing electronic and paper VAS have reported high correlations and good agreement.

References:

Jamison RN, et al. Pain. 2002;99:341–347. PMID: 12237213

Escalona-Marfil C, et al. J Med Internet Res. 2020;22:e13468. PMID: 32049063

Turnbull A, et al. J Med Internet Res. 2020;22:e18284. PMID: 32940621

These studies evaluated electronic VAS systems other than rVAS. They do not establish the validity of rVAS itself or its equivalence to paper VAS in every population or use case.

【Works offline and keeps data local】

• Core features work without an internet connection
• No ads
• No account required
• Measurement data is stored on your device
• No automatic transmission to external servers
• Export through the Files app, AirDrop, or the share sheet

Data is shared only when you choose to export or share it. We recommend using anonymized or pseudonymized participant IDs rather than directly identifying information such as names.

【Try all features free for 14 days】

All features are available free for 14 days from first use.

After the trial, users without a subscription or one-time purchase can no longer create new projects or start new measurement sessions. Saved projects and results remain viewable and exportable.

rVAS is not a medical device and is not intended for diagnosis or treatment decisions. It is designed to support the collection of subjective ratings in research and survey settings.

Terms of Use: https://r-2gg.pages.dev/terms-en