Used and loved by millions
Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
rationale is required
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "rationale is required" is correct and usable in written English.
You can use it when indicating that a justification or reasoning is necessary for a particular decision or action. Example: "Before we proceed with the project, a rationale is required to explain the chosen approach."
✓ Grammatically correct
Science
News & Media
Formal & Business
Alternative expressions(2)
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Human-verified examples from authoritative sources
Exact Expressions
1 human-written examples
Clinical, as well as statistical, rationale is required for combining treatments.
Science
Human-verified similar examples from authoritative sources
Similar Expressions
57 human-written examples
In all cases, use of several programs based on different rationales is required to improve the quality of the prediction of sub-cellular location or function of a protein.
5) A systematic search and evaluation of evidence Conformance with evidence would require expert judgment The quality of decisions should be higher because rationales are required, there is less scope for decisions to be based on considerations other than the available evidence e.g. lobbying and political pressure, though lobbying will still occur.
Science
Specifically, research is required to understand the rationale behind milk and alternative beverage purchasing behaviors, including pricing and availability.
Science
Appropriate monitoring of vector insecticide susceptibility is required to provide the rationale for optimal insecticide selection in vector control programs.
Science
In habeas-corpus proceedings, the government is required to bring a prisoner — the body — before a judge and provide a legal rationale for his continued imprisonment.
News & Media
However, this study utilised the Flavell et al. perspective-taking logic task in which children are required to provide rationales for a guessing game strategy.
In those cases that were indeterminate, the panelists were required to supply the rationale for their decision.
Science
Neither of these rationales is relevant to foster carers, who are required to have a spare room in order to provide homes for vulnerable children".
News & Media
The students were required to articulate and share their rationales using the space, namely, the rationale space.
That rationale should disappear in 2014 when virtually all Americans will be required to buy insurance or pay a penalty.
News & Media
Expert writing Tips
Best practice
When requesting a rationale, be specific about what aspects of the decision or action need justification to ensure the response addresses the key concerns.
Common error
Avoid excessive use of the passive voice when using "rationale is required". Instead of saying "A rationale is required by the committee", opt for a more direct construction like "The committee requires a rationale" for clarity and conciseness.
Source & Trust
82%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "rationale is required" functions as a request or demand for a justification or explanation. It clearly states that providing a reason or underlying logic is not optional but necessary. As Ludwig confirms, the phrase is correct and usable in English.
Frequent in
Science
35%
News & Media
33%
Formal & Business
32%
Less common in
Encyclopedias
0%
Wiki
0%
Reference
0%
Ludwig's WRAP-UP
In summary, the phrase "rationale is required" is a grammatically sound and frequently used expression across various professional domains, according to Ludwig. It serves to demand or strongly request a clear and justified explanation for a decision or action. While adaptable to different contexts, it maintains a formal tone and is commonly found in science, news media, and formal business communications. Understanding its function and purpose allows for its effective use in ensuring accountability and transparency in decision-making processes. Consider using alternatives such as "justification is needed" or "reasoning is necessary" when appropriate.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
justification is needed
Emphasizes the necessity of providing reasons to defend or explain an action or decision; more direct than the original phrase.
reasoning is necessary
Highlights the logical thought process that must be presented; slightly more formal.
explanation is required
Focuses on clarifying the 'why' behind something; emphasizes making something understandable.
substantiation is needed
Implies a need for evidence to support a claim or action; more formal and emphasizes proof.
elaboration is necessary
Suggests a need for greater detail and development of an idea; appropriate when more depth is needed.
a basis is required
Highlights the need for a foundational reason or principle; emphasizes the underlying support.
underlying logic is required
Focuses specifically on the logical structure supporting an argument or decision.
grounds must be provided
A more formal way of saying that reasons or justifications are expected.
supporting evidence is needed
Highlights the need for empirical data to back up a claim or decision.
a valid argument is required
Emphasizes the need for a coherent and well-structured explanation that is logically sound.
FAQs
How do I use "rationale is required" in a sentence?
Use "rationale is required" to indicate that a justification or explanation is needed. For example, "Before the project can proceed, a detailed rationale is required."
What's a more formal alternative to "rationale is required"?
A more formal alternative could be "justification is necessary" or "an explanation is mandated". Both convey a similar meaning with a heightened sense of formality.
What can I say instead of "rationale is required"?
You can use alternatives like "justification is needed", "reasoning is necessary", or "explanation is required" depending on the context.
Is "rationale is required" the same as "rationale is needed"?
While similar, "rationale is required" suggests a stronger demand or mandate, whereas "rationale is needed" implies a necessity that may be less forceful.
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Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
82%
Authority and reliability
4.5/5
Expert rating
Real-world application tested