Skip to main content
Key Specialties
Cardiology Diabetology Endocrinology Gastroenterology Geriatrics and Gerontology Gynecology and Obstetrics Hematology Infectious Disease Internal Medicine Nephrology Neurology Oncology Pediatrics Respiratory Medicine Rheumatology Surgery
Congress Coverage
2024 ACC Congress 2023 ESMO Congress 2023 EASD Congress 2023 ERS Congress 2023 ESC Congress 2023 EHA Congress 2023 ASCO Annual Meeting
Clinical Collections
Advances in Alzheimer’s

Keynote webinar | Spotlight on sleep in brain health

LIVE: Thursday 2nd May 2024, 18:00-19:30 (CEST)

Quality sleep is essential for health. But what happens to our brains when sleep patterns are disturbed? Join our experts to explore the interplay between sleep disruption and neurological diseases, and the questions that you need to be asking your patients to help you prevent the harmful effects of sleep deprivation.
ADVANCED SEARCH
Log in
Top
Quality of Life Research
Published in: Quality of Life Research 10/2021

Open Access 01-10-2021 | Dementia

Estimating the minimum important difference in the DEMQOL instrument in people with dementia

Authors: Ellen C. Lee, Jessica Wright, Stephen J. Walters, Cindy L. Cooper, Gail A. Mountain

Published in: Quality of Life Research | Issue 10/2021

Login to get access

Abstract

Purpose

The Dementia-Related Quality of Life (DEMQOL) measure and the DEMQOL-Utility Score (DEMQOL-U) are validated tools for measuring quality of life (QOL) in people with dementia. What score changes translate to a clinically significant impact on patients’ lives was unknown. This study establishes the minimal important differences (MID) for these two instruments.

Methods

Anchor-based and distribution-based methods were used to estimate the MID scores from patients enrolled in a randomised controlled trial. For the anchor-based method, the global QOL (Q29) item from the DEMQOL was chosen as the anchor for DEMQOL and both Q29 and EQ-5D for DEMQOL-U. A one category difference in Q29, and a 0.07 point difference in EQ-5D score, were used to classify improvement and deterioration, and the MID scores were calculated for each category. These results were compared with scores obtained by the distribution-based methods.

Results

A total of 490 people with dementia had baseline DEMQOL data, of these 386 had 8-month data, and 344 had 12-month DEMQOL data. The absolute change in DEMQOL for a combined 1-point increase or decrease in the Q29 anchor was 5.2 at 8 months and 6.0 at 12 months. For the DEMQOL-U, the average absolute change at 8 and 12 months was 0.032 and 0.046 for the Q29 anchor and 0.020 and 0.024 for EQ-5D anchor.

Conclusion

We present MID scores for the DEMQOL and DEMQOL-U instruments obtained from a large cohort of patients with dementia. An anchored-based estimate of the MID for the DEMQOL is around 5 to 6 points; and 0.02 to 0.05 points for the DEMQOL-U. The results of this study can guide clinicians and researchers in the interpretation of these instruments comparisons between groups or within groups of people with dementia.

Trial Registration Number and date of registration:

ISRCTN17993825 on 11th October 2016.
Appendix
Available only for authorised users
Literature
1.
2.
Prince, M., Knapp, M., Guerchet, M., McCrone, P., Prina, M., Comas-Herrera, A., et al. (2014). Dementia UK Update (2nd ed.). London: Alzheimer’s Society.
3.
4.
5.
6.
Winblad, B., Amouyel, P., Andrieu, S., Ballard, C., Brayne, C., Brodaty, H., et al. (2016). Defeating Alzheimer’s disease and other dementias: A priority for European science and society. Lancet Neurology, 15, 455–532.CrossRef
7.
Smith, S., Lamping, D., Banerjee, S., Harwood, R., Foley, B., Smith, P., et al. (2005). Measurement of health-related quality of life for people with dementia: Development of a new instrument (DEMQOL) and an evaluation of current methodology. Health Technology Assessment, 9(10), 1–93.CrossRef
8.
Mulhern, B., Rowen, D., Brazier, J., Smith, S., Romeo, R., Tait, R., et al. (2013). Development of DEMQOL-U and DEMQOL-PROXY-U: Generation of preference-based indices from DEMQOL and DEMQOL-PROXY for use in economic evaluation. Health Technology Assessment, 17(5), 1–140.CrossRef
9.
Walters, S. J., & Brazier, J. E. (2005). Comparison of the minimally important difference for two health state utility measures: EQ-5D and SF-6D. Quality of Life Research, 14(6), 1523–1532.CrossRef
10.
Jaeschke, R., Singer, J., & Guyatt, G. H. (1989). Measurement of health status. Ascertaining the minimal clinically important difference. Controlled Clinical Trials, 10(4), 407–415.CrossRef
11.
Fayers, P. M., & Machin, D. (2016). Quality of life : The assessment, analysis, and reporting of patient-reported outcomes (3rd ed.). Chichester: Wiley-Blackwell.
12.
Revicki, D., Hays, R. D., Cella, D., & Sloan, J. (2008). Recommended methods for determining responsiveness and minimally important differences for patient-reported outcomes. Journal of Clinical Epidemiology, 61, 102–109.CrossRef
13.
Wright, J., Foster, A., Cooper, C., Sprange, K., Walters, S., Berry, K., et al. (2019). Study protocol for a randomised controlled trial assessing the clinical and cost-effectiveness of the Journeying through Dementia (JtD) intervention compared to usual care. British Medical Journal Open, 9(9), e029207.
14.
EuroQol Research Foundation (2019). EuroQol research foundation. EQ-5D-5L User Guide
15.
StataCorp (2019). Stata statistical software: Release 16
16.
17.
van Hout, B., Janssen, M. F., Feng, Y.-S., Kohlmann, T., Busschbach, J., Golicki, D., et al. (2012). Interim scoring for the EQ-5D-5L: Mapping the EQ-5D-5L to EQ-5D-3L value sets. Value in health the journal of the International Society for Pharmacoeconomics and Outcomes Research, 15(5), 708–715.CrossRef
18.
King, M. T. (2011). A point of minimal important difference (MID): A critique of terminology and methods. Expert Review of Pharmacoeconomics and Outcomes Research, 11(2), 171–184.CrossRef
19.
Cohen, J. (1988). Statistical power analysis for the behavioral sciences (2nd ed.). Hillsdale, NJ: Lawrence Earlbaum Associates.
20.
Jacobson, N. S., & Truax, P. (1991). Clinical significance: A statistical approach to defining meaningful change in psychotherapy research. Journal of Consulting and Clinical Psychology, 59(1), 12–19.CrossRef
21.
Banerjee, S., Hellier, J., Romeo, R., Dewey, M., Knapp, M., Ballard, C., et al. (2013). Study of the use of antidepressants for depression in dementia: The HTA-SADD trial- A multicentre, randomised, double-blind, placebo-controlled trial of the clinical effectiveness and cost-effectiveness of sertraline and mirtazapine. Health Technology Assessment, 17(7), 1–43.CrossRef
22.
Charlesworth, G., Burnell, K., Crellin, N., Hoare, Z., Hoe, J., Knapp, M., et al. (2016). Peer support and reminiscence therapy for people with dementia and their family carers: A factorial pragmatic randomised trial. Journal of Neurology Neurosurgery and Psychiatry, 87(11), 1218–1228.CrossRef
23.
Low, L.-F., Brodaty, H., Goodenough, B., Spitzer, P., Bell, J.-P., Fleming, R., et al. (2013). The sydney multisite intervention of laughter bosses and elder clowns (SMILE) study: Cluster randomised trial of humour therapy in nursing homes. British Medical Journal Open, 3(1), 1–8.
24.
Orgeta, V., Leung, P., Yates, L., Kang, S., Hoare, Z., Henderson, C., et al. (2015). Individual cognitive stimulation therapy for dementia: A clinical effectiveness and cost-effectiveness pragmatic, multicentre, randomised controlled trial. Health Technology Assessment, 19(64), 7–73.CrossRef
25.
Orrell, M., Aguirre, E., Spector, A., Hoare, Z., Woods, R. T., Streater, A., et al. (2014). Maintenance cognitive stimulation therapy for dementia: Single-blind, multicentre, pragmatic randomised controlled trial. British Journal of Psychiatry, 204(6), 454–461.CrossRef
26.
Clare, L., Kudlicka, A., Oyebode, J. R., Jones, R. W., Bayer, A., Leroi, I., et al. (2019). Goal-oriented cognitive rehabilitation for early-stage Alzheimer’s and related dementias: The GREAT RCT. Health technology assessment (Winchester, England, 23(10), 1–242.CrossRef
27.
Crotty, M., Killington, M., Liu, E., Cameron, I. D., Kurrle, S., Kaambwa, B., et al. (2019). Should we provide outreach rehabilitation to very old people living in nursing care facilities after a hip fracture? A randomised controlled trial. Age and ageing, 48(3), 373–380.CrossRef
28.
Goldberg, S. E., Bradshaw, L. E., Kearney, F. C., Russell, C., Whittamore, K. H., Foster, P. E. R., et al. (2013). Care in specialist medical and mental health unit compared with standard care for older people with cognitive impairment admitted to general hospital: Randomised controlled trial (NIHR TEAM trial). BMJ, 347, 7917.CrossRef
29.
Wenborn, J., Hynes, S., Moniz-Cook, E., Mountain, G., Poland, F., King, M., et al. (2016). Community occupational therapy for people with dementia and family carers (COTiD-UK) versus treatment as usual (Valuing Active Life in Dementia [VALID] programme): Study protocol for a randomised controlled trial. Trials, 17(1), 1–10.CrossRef
30.
31.
Park, M. H., Black, N., Ritchie, C. W., Hendriks, A. A. J., & Smith, S. C. (2017). Is the effectiveness of memory assessment services associated with their structural and process characteristics? International Journal of Geriatric Psychiatry, 33(1), 75–84.CrossRef
32.
Banerjee, S., Smith, S. C., Lamping, D. L., Harwood, R. H., Foley, B., Smith, P., et al. (2006). Quality of life in dementia: more than just cognition. An analysis of associations with quality of life in dementia. Journal of Neurological Neurosurgery and Psychiatry, 77(2), 146–148.CrossRef
33.
Turner, D., Schünemann, H. J., Griffith, L. E., Beaton, D. E., Griffiths, A. M., Critch, J. N., et al. (2010). The minimal detectable change cannot reliably replace the minimal important difference. Journal of Clinical Epidemiology, 63(1), 28–36.CrossRef
34.
de Vet, H. C. W., & Terwee, C. B. (2010). The minimal detectable change should not replace the minimal important difference. Journal of Clinical Epidemiology, 63(7), 804–805.CrossRef
35.
Alanne, S., Roine, R. P., Räsänen, P., Vainiola, T., & Sintonen, H. (2015). Estimating the minimum important change in the 15D scores. Quality of Life Research, 24(3), 599–606.CrossRef
36.
Raman, S., Ding, K., Chow, E., Meyer, R. M., van der Linden, Y. M., Roos, D., et al. (2018). Minimal clinically important differences in the EORTC QLQ-C30 and brief pain inventory in patients undergoing re-irradiation for painful bone metastases. Quality of Life Research, 27(4), 1089–1098.CrossRef
37.
Hays, R. D., Farivar, S. S., & Liu, H. (2005). Approaches and recommendations for estimating minimally important differences for health-related quality of life measures. COPD Journal of Chronic Obstructive Pulmonary Disease, 2(1), 63–67.CrossRef
Metadata
Title
Estimating the minimum important difference in the DEMQOL instrument in people with dementia
Authors
Ellen C. Lee
Jessica Wright
Stephen J. Walters
Cindy L. Cooper
Gail A. Mountain
Publication date
01-10-2021
Publisher
Springer International Publishing
Keywords
Dementia
Dementia
Published in
Quality of Life Research / Issue 10/2021
Print ISSN: 0962-9343
Electronic ISSN: 1573-2649
DOI
https://doi.org/10.1007/s11136-021-02900-7

Other articles of this Issue 10/2021

Quality of Life Research 10/2021 Go to the issue

OriginalPaper

Could the EQ-5D-3L predict all-cause mortality in older Chinese? Evidence from a 5-year longitudinal study in eastern China

OriginalPaper

Mapping the Memorial Anxiety Scale for Prostate Cancer to the SF-6D

OriginalPaper

Health-related quality of life outcomes and influencing factors in patients with unruptured intracranial aneurysms after endovascular treatment

OriginalPaper

An item analysis according to the Rasch model of the German 12-item WHO Disability Assessment Schedule (WHODAS 2.0)

OriginalPaper

The effect of functioning on Quality of Life Inventory-Disability measured quality of life is not mediated or moderated by parental psychological distress

OriginalPaper

Health-related quality of life after first-ever acute ischemic stroke: associations with cardiovascular health metrics