The Functional Dementia Scale (FDS) can be used to evaluate the behavior of a patient with dementia. It consists of 20 items divided into 3 subscales. It can be monitored over time and can be used to assess the effectiveness of interventions. The authors are from Duke University in Durham, North Carolina.



(1) activities of daily living

(2) orientation

(3) affect


Behaviors (20):

(1) has difficulty in completing simple tasks on own (e.g., dressing, bathing, doing arithmetic)

(2) spends time either sitting or in apparently purposeless activity

(3) wanders at night or needs to be restrained to prevent wandering

(4) hears things that are not there

(5) requires supervision or assistance in eating

(6) loses things

(7) appearance is disorderly if left to own devices

(8) moans

(9) cannot control bowel function

(10) threatens to harm others

(11) cannot control bladder function

(12) needs to be watched so doesn't injury self (e.g., by careless smoking, leaving the stove on, falling)

(13) destructive of materials around him or her (e.g., breaks furniture, throws food trays, tears up magazines)

(14) shouts or yells

(15) accuses others of doing him or her bodily harm or stealing possessions when you are sure that the accusations are not true

(16) is unaware of limitations imposed by illness

(17) becomes confused and does not know where he/she is

(18) has trouble remembering

(19) has sudden changes of mood (e.g., gets upset, angered, cries easily)

(20) if left alone, wanders aimlessly during the day or needs to be restrained to prevent wandering





little of the time


some of the time


good part of the time


most of the time


all of the time



activities of daily living subscale =

= SUM(points for items 1, 2, 5, 7, 9, 11 and 12)


orientation subscale =

= SUM(points for item 3, 6, 16, 17, 18 and 20)


affect subscale =

= SUM(points for items 4, 8, 10, 13, 14, 15, and 19)


total functional dementia scale =

= SUM(points for all 20 behaviors)



• minimum activities of daily living and affect subscales: 7

• minimum orientation subscale: 6

• minimum total score: 20

• maximum activities of daily living and affect subscales: 28

• maximum orientation subscale: 24

• maximum total score: 80

• The higher the score, the more problematic the patient's behavior.



• internal consistency: Cronbach's alpha 0.90

• test-retest correlation: 0.88

• Pearson correlation coefficient with the SET test: 0.48

• Pearson correlation coefficient with the SPMSQ: 0.39 (standard cognitive measures tend to be insensitive to the functional disabilities and management problems found with dementia)


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