---
title: "Randomised non-comparative trial"
chunk: 1/1
source: "https://en.wikipedia.org/wiki/Randomised_non-comparative_trial"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T10:02:57.097615+00:00"
instance: "kb-cron"
---

A randomised non-comparative trial, RNCT (or also non-comparative randomised trial), is a type of clinical trial where participants are randomised to different conditions (arms), but where the primary analysis involves comparing each arm separately to a historical control, predefined benchmark or something else, with no formal comparison between the two arms.
The study design appears to have arisen in oncology, where single-arm studies are not unusual. It promises reduced sample size requirements. An RNCT acts like multiple single-arm designs run concurrently. A review found RNCTs dating back to 2002, and having been used in high-profile oncology studies and also beyond oncology.
The design has been criticised by statisticians. It is unclear what benefit randomisation adds compared to running separate single-arm studies. Pavlos Msaouel described the use of the word "randomisation" as merely being "talismanic" in a 2025 article, it leading readers to think the study has the benefits of a randomised controlled trial (RCT). While the point of an RNCT is not to have a comparison between arms, about half of reported RNCTs still reported some sort of comparison.


== References ==