Hong Life CalculatorsUnderstanding the BIMS calculator — concept and principle
This calculator scores the Brief Interview for Mental Status (BIMS), the short cognitive screen in Section C of the US nursing-home Minimum Data Set (MDS 3.0). It adds the points for repeating three words, orientation to year, month and day, and recalling the words, and gives the cognitive status band. Nursing-home staff, MDS coordinators and students use it.
How it is calculated
- Repetition of sock, blue, bed: 0–3
- Year: 3 correct; 2 missed by 1 year; 1 missed by 2–5 years; 0 otherwise
- Month: 2 within 5 days; 1 missed by 6 days to 1 month; 0 otherwise
- Day of the week: 1 correct; 0 otherwise
- Recall of each word: 2 without a cue; 1 after a category cue; 0 not recalled
- Total 0–15: 13–15 cognitively intact; 8–12 moderately impaired; 0–7 severe impairment
The principle
The BIMS tests three areas briefly: registration (repeating words), orientation (knowing the date) and short-term memory (recalling words a few minutes later). Giving fewer points for words recalled only after a cue separates true recall from recognition. The bands guide care planning in nursing homes. They assume the person could hear the questions and was not delirious; the interview must be completed in full, and a stopped interview is not scored.
Worked example
Defaults: repeated all three words (3); correct year (3); month within 5 days (2); correct day (1); recalled sock without cue (2), blue after cue (1), bed without cue (2).
- Score = 3 + 3 + 2 + 1 + 2 + 1 + 2 = 14.
- Band 13–15: Cognitively intact.
How to read the result
A score of 13–15 suggests intact cognition on this brief screen. Lower scores call for closer observation and possibly a fuller assessment, especially if the score has dropped. Hearing problems, language barriers, sedation or delirium can lower the score without dementia.
Common mistakes
- Giving cues before the resident has had a chance to recall freely.
- Scoring an incomplete interview.
- Ignoring hearing aids or glasses that the resident needs.
- Interpreting the score as a diagnosis of dementia.
Frequently asked questions
What does a BIMS score of 14 mean?
It falls in the 13–15 band, cognitively intact on this screen.
What are the three BIMS words?
Sock, blue and bed, with cues "something to wear", "a colour" and "a piece of furniture".
Can the BIMS diagnose dementia?
No. It screens for cognitive impairment; diagnosis needs a full clinical assessment.
Sources: Centers for Medicare & Medicaid Services, Long-Term Care Facility Resident Assessment Instrument 3.0 User's Manual, Chapter 3, Section C (October 2024)