What is the difference between client doesn't know, client prefers not to answer and data not collected?
Author: Betty | Date Created: December 12, 2025 |
What this is
This article explain the difference between client doesn't know (CDN), client prefers not to answer (PNA) and data not collected (DNC) and why the difference matters.
What is the difference between client doesn't know, client prefers not to answer and data not collected?
HMIS uses specific response options to show why a piece of information is missing. These options are important because they help distinguish client choice from staff or system error.
Client Doesn’t Know
This means the client genuinely does not know the answer.
Examples:
- They don’t know how long they’ve been staying somewhere.
- They aren’t sure about their income or benefits.
- They don’t know the exact date something happened.
Key point:
👉 The client wants to answer, but they don’t have the information.
Client Prefers Not to Answer
This means the client knows the answer but chooses not to share it.
Reasons might include:
- They feel the question is too personal.
- They don’t trust the system yet.
- They’re uncomfortable discussing sensitive topics.
Key point:
👉 The client intentionally declines to provide the information.
Data Not Collected
This means the information should have been collected but wasn’t.
This is not about the client.
It is about staff or system not getting the answer.
Examples:
- Staff forgot to ask the question.
- A required field was skipped.
- The interview was cut short.
- The question was missed due to error.
Key point:
👉 It reflects missing data due to staff or system error—not the client.
Why the Differences Matter
Choosing the correct option helps:
- Maintain accurate HMIS data
- Avoid errors on reports
- Show funders that missing data was due to client choice—not staff mistakes
- Improve the overall quality of community data
“Data Not Collected” is always the least desirable option because it indicates a problem with data entry, workflow, or training.