• Developed to assess the complex activities of daily living (ADLs) for older adults living in the community. It assesses a person’s ability to perform tasks such as using a telephone, doing laundry, and handling finances.
  • Each ability measured by the scale relies on either cognitive or physical function, though all require some degree of both.

Clinical Considerations

  • The IADL is an easy to administer and provides various response options for each item enabling flexibility when scoring. It measures more complex (instrumental) levels of functioning than other ADL instruments. The IADL scale is therefore likely to be more sensitive in detecting earlier, less severe dysfunction.
  • The content of IADL measures often reflects specific cultural concerns. For example, British measures frequently include the ability to make a cup of tea. There is also potential for gender bias as the scale may overemphasize tasks customarily performed by women and thus overestimate dependency in men.
  • Only one study, with findings of weak construct validity, has been performed to test the IADL psychometric properties among an SCI population

ICF Domain

Activity ▶ General Tasks and Demands

Number of Items

8

Administration

  • Can be administered using self-report or by interview
  • The patient or a family member or caregiver may provide answers.
  • Responses to each of the eight items in the scale will vary ranging from independence in performing the activity to not performing the activity at all.
  • Approximately 10 minutes are required for administration.

Equipment

None

Scoring

  • Responses range from 0 (unable or partially able) to 1 (able).
  • Individual items are summed to give a total score. The composite IADL score ranges from 0 (maximum dependence) to 8 (independent).

Languages

English

Training Required

No special training required

Availability

May use with permission of publisher (Gerontological Society of America). The IADL worksheet can be found here. (https://www.abramsoncenter.org/media/1197/instrumental-activities-of-daily-living.pdf)

Measurement Property Summary

Number of studies reporting psychometric properties: 1

Interpretability

  • Item responses are summed to derive a scale score with higher scores indicating greater independence.
  • No normative data has been established for the SCI population.
  • Published data is available to compare results for individuals with SCI (see interpretability section of Study Details sheet).
  • MCID: not established in SCI population
  • SEM: not established in SCI population
  • MDC: not established in SCI population

Reliability

No values have been reported at this time for the reliability of the IADL for the SCI population.

Validity – Low to Moderate

  • Low correlation with the Short Form-36 Mental subscales summary: Pearson’s r = -0.262
  • Low correlation with the Short Form-12 Physical subscales summary: Pearson’s r = -0.272
  • Moderate correlation with the Short Form-12 Mental subscale summary: Pearson’s r = -0.370
  • Moderate correlation with the Short Form-36 Physical subscales summary: Pearson’s r = -0.357
  • Moderate correlation with the Quality of Well-Being Scale: Pearson’s r = -0.454

(Andresen et al. 1999; n=183, mean age: 50.5 (range 21-81); 82 people with quadriplegia)

Responsiveness

No values were reported for the responsiveness of the IADL for the SCI population.

Floor/Ceiling Effect

A slight floor effect detected (13.5% of participants had lowest score).

(Andresen et al. 1999; n=183, mean age: 50.5 (range 21-81); 82 people with quadriplegia)

Reviewers

Dr. Carlos L. Cano-Herrera, Tyra Chu

Date Last Updated

December 31, 2024

Andresen EM, Fouts BS, Romeis JC, Brownson CA. Performance of health-related quality-of-life instruments in a spinal cord injured population. Arch Phys Med Rehabil, 1999; 80: 877-84.
http://www.ncbi.nlm.nih.gov/pubmed/10453762

Lawton G, Lundgren-Nilsson A, Biering-Sorensen F, Tesio L, Slade A, Penta M, Grimby G, Ring H, Tennant A. Cross-cultural validity of FIM in spinal cord injury. Spinal Cord 2006; 44: 746-752.
http://www.ncbi.nlm.nih.gov/pubmed/16389268