F71.1: Moderate mental retardation Significant impairment of behaviour requiring attention or treatment

Your intellectual faculties are restricted. Your behavior has changed significantly as a result.

Every human being has a degree of mental, or cognitive, ability. This ability is also known as intelligence. Mental abilities include learning and applying new things. They also include the ability to speak, move and how to interact with other people. Mental ability, or aptitude, can be established with specific tests. These tests are called intelligence, or IQ, tests. When these mental abilities are diminished, it’s usually been like this since childhood. You can practice and in this way get better at mental abilities and dealing with other people.

You have an IQ of 35-49. This corresponds to a mental age of 6 to 9 years old. You have a certain degree of independence and can talk to other people sufficiently. You need a certain degree of support in your everyday life and at work.

Your diminished mental ability has changed your behavior significantly. You may therefore need treatment.

Additional indicator

On medical documents, the ICD code is often appended by letters that indicate the diagnostic certainty or the affected side of the body.

  • G: Confirmed diagnosis
  • V: Tentative diagnosis
  • Z: Condition after
  • A: Excluded diagnosis
  • L: Left
  • R: Right
  • B: Both sides

Further information


This information is not intended for self-diagnosis and does not replace professional medical advice from a doctor. If you find an ICD code on a personal medical document, please also note the additional indicator used for diagnostic confidence.
Your doctor will assist you with any health-related questions and explain the ICD diagnosis code to you in a direct consultation if necessary.


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