Borderline intellectual functioning (BIF) isn’t currently a stand-alone diagnosis. Some diagnostic guidelines use it as a descriptive code, while others include it within a broader spectrum of intellectual development disorders.

Intelligence quotient (IQ) is a numerical score representing your intelligence, which is the collective representation of your cognitive (mental) abilities and capacity. IQ is determined through standardized tests and is scored from an average of 100 points.

IQ tests don’t definitively diagnose any specific condition. They’re clinical tools that help provide insight into your intellectual function. But scoring low on an IQ test doesn’t mean you have an intellectual impairment. IQ tests assess components of intellectual ability, but they aren’t as good at predicting potential or overall cognitive effectiveness.

Low IQ scores become clinically relevant when they’re supported by lived experience.

Borderline intellectual functioning (BIF) is a specific IQ margin between the formal diagnosis of intellectual disability (ID) and average intellectual function.

An IQ score between 70 and 85 qualifies as BIF, supported by various developmental delays and functional deficits that affect independence and daily life.

BIF affects an estimated 12–14% of the population. But without universal diagnostic guidelines, it’s difficult to know how many people are truly affected.

An IQ score of 70 or less is associated with the formal diagnosis of ID. This diagnosis involves clear impairment that can affect a wide range of functions, such as interpersonal skills, understanding of time, and language comprehension.

Uses in diagnosis

Unlike ID, BIF is not a stand-alone diagnosis. It’s currently a “v-code” in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition, text revision (DSM-5-TR), which is the primary diagnostic guidebook used by mental health professionals in the United States.

V-codes are diagnostic descriptors. Like “specifiers,” another type of informative label, v-codes are used to add detail to an overall diagnosis. For example, a v-code of BIF would be used when you receive a diagnosis of a condition and certain intellectual challenges are relevant to your symptoms and treatment plan.

In the past, BIF was also a descriptive code in the International Classification of Diseases, 10th revision, clinical modification (ICD-10-CM), another internationally used diagnostic manual.

The 11th version of the ICD, which has officially been in use since 2022, mentions BIF within a new category called disorders of intellectual development. BIF is still not considered an independent diagnosis, but it is recognized as a condition requiring early intervention.

The debate between descriptive codes and formal diagnosis

Many experts feel that BIF should have a clear diagnostic designation beyond a DSM v-code or the general support recommendations in the latest ICD.

According to the attendees of a 2017 consensus meeting in Girona, Spain, BIF poses specific health challenges that warrant individualized, targeted support. For example, people with BIF have increased risks for social exclusion and mental and physical health complications.

Creating a formal diagnostic space for people with BIF could help increase awareness and early access to interventions and support networks.

BIF varies widely in presentation, depending on which areas of cognitive function it affects.

Overall, it’s marked by intellectual functions and adaptive behaviors that are below the expected level for your age and life circumstances. In this way, it affects the same areas as ID but typically involves a lesser degree of impairment.

BIF can include challenges related to:

  • problem-solving or logical reasoning
  • learning
  • communication and language
  • self-expression
  • interpersonal interactions
  • comprehension
  • memory recall and retention

In daily life, BIF can look different for each person. For some people, it may be most evident at work when they’re interacting with others or navigating deadlines. For others, it might affect practical skills such as managing finances.

There’s no specific treatment for BIF. It’s typically treated alongside underlying conditions, such as neurodevelopmental disorders, and the overarching diagnosis of another condition determines your treatment plan.

Interventions for BIF that are used across various conditions include:

  • community and educational skill-building programs
  • educational and occupational accommodations
  • vocational (specific job skill) training
  • cognitive behavioral therapy (CBT)
  • family education
  • case management
  • housing services
  • day programs for adults

Can you get disability for borderline intellectual functioning?

BIF may qualify for disability benefits through the Social Security Administration (SSA) under the category of “mental disorders, neurodevelopmental disorders.”

The SSA determines disability benefits on an individual basis. You’ll need to provide medical evidence that outlines your history with BIF and proof of related impairments. Not everyone with BIF may be granted disability.

For insurance purposes, BIF is coded under V62.89 in the DSM-5-TR. In the ICD-10-CM, it’s coded as R41.83.

The ICD-11 is the most current version of the ICD, but because it’s a relatively new release, many clinical settings may still rely on the ICD-10-CM.

BIF is indicated by an IQ score between 70 and 85, with related impairment across varying areas of cognitive and adaptive function. While there is some debate about whether it should be a formal diagnosis, BIF by any name can cause challenges that affect daily life.

Depending on other conditions you may have, BIF interventions can include CBT, family education, vocational training, and other supportive programs.