title: Values of the Minimal Clinically Important Difference for the Neuropsychiatric Inventory Questionnaire in Individuals with Dementia.
abstract: OBJECTIVE
  To estimate the minimal clinically important difference (MCID) for the Neuropsychiatric Inventory Questionnaire (NPI-Q), a widely used measure of behavioral and psychological symptoms of dementia (BPSDs) and associated caregiver stress.
  
  
  METHODS
  Ten registered nurses rated the severity of BPSDs and caregiver distress using the NPI-Q during six monthly assessments and an external reference, a 7-point Likert-type global rating of BPSDs change during five monthly assessments from the second to the sixth month. An anchor-based (global ratings of change) approach and a distribution-based (standard error of measurement) approach were used to determine the MCID for the NPI-Q severity and distress subscales.
  
  
  METHODS
  Long-term care facility.
  
  
  METHODS
  Nonbedridden residents with dementia (n = 45) and registered nurses (n = 10).
  
  
  METHODS
  NPI-Q (severity and caregiver distress subscales) and global ratings of changes in BPSDs on a 7-point Likert-type scale.
  
  
  RESULTS
  The NPI-Q MCID ranges were 2.77 to 3.18 for severity and 3.10 to 3.95 for distress. Residents in the highest NPI-Q tertile at baseline had higher MCID severity (3.62) and distress (5.08) scores than those in the lowest tertile (severity (2.40), distress (3.10)).
  
  
  CONCLUSIONS
  This study provides an estimate of the MCID for severity and distress subscales of the NPI-Q, which can help clinicians and researchers determine whether NPI-Q change scores within a group of individuals with dementia are beyond measurement error and are clinically important.
authors.affiliation: School of Occupational Therapy, College of Medicine, National Taiwan University, Taipei, Taiwan.
authors.forename: Hui-Fen
authors.initials: HF
authors.lastname: Mao
authors.affiliation: School of Occupational Therapy, College of Medicine, National Taiwan University, Taipei, Taiwan.
authors.forename: Chun-An
authors.initials: CA
authors.lastname: Kuo
authors.affiliation: Department of Physical Therapy, I-Shou University, Kaohsiung City, Taiwan.
authors.forename: Wen-Ni
authors.initials: WN
authors.lastname: Huang
authors.affiliation: Cleveland Clinic, Las Vegas, Nevada.
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Cummings
authors.affiliation: Department of Psychiatry, National Taiwan University Hospital and College of Medicine, National Taiwan University, Taipei, Taiwan.
authors.forename: Tzung-Jeng
authors.identifier: http://orcid.org/0000-0001-7894-9484
authors.initials: TJ
authors.lastname: Hwang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017028:Caregivers / Q000523:psychology*; D003704:Dementia / Q000523:psychology*; D005260:Female; D006801:Humans; D008134:Long-Term Care; D008297:Male; D009483:Neuropsychological Tests; D011594:Psychometrics; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D013624:Taiwan
keywords: Neuropsychiatric Inventory Questionnaire (NPI-Q); behavioral and psychological symptoms of dementia (BPSDs); dementia; minimal clinically important difference