TY - JOUR
T1 - Minimum clinically important difference of the Social Functioning in Dementia Scale (SF-DEM)
T2 - cross-sectional study and Delphi survey
AU - Levene, Tamara
AU - Livingston, Gill
AU - Banerjee, Sube
AU - Sommerlad, Andrew
N1 - Publisher Copyright:
© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.
PY - 2022/3/29
Y1 - 2022/3/29
N2 - Objectives Good social functioning is important for people living with dementia and their families. The Social Functioning in Dementia Scale (SF-DEM) is a valid and reliable instrument measuring social functioning in dementia. However the minimum clinically important difference (MCID) has not yet been derived for SF-DEM. This study aims to define the MCID for the SF-DEM. Design We used triangulation, incorporating data from a cross-sectional study to calculate the MCID using distribution-based and anchor-based methods, and a Delphi survey. Setting and participants The cross-sectional survey comprised 299 family carers of people with dementia. Twenty dementia experts (researchers, clinicians, family carers) rated whether changes on clinical vignettes represented a meaningful change in the Delphi survey. Primary outcome measures We calculated the distribution-based MCID as 0.5 of an SD for each of the three SF-DEM domains (1 - spending time with others, 2 - communicating with others, 3 - sensitivity to others). We used the carers' rating of social functioning to calculate the anchor-based MCID. For the Delphi survey, we defined consensus as ≥75% agreement. Where there was lack of consensus, experts were asked to complete a further survey round. Results We found that 0.5 SD of SF-DEM was 1.9 points, 2.2 and 1.4 points in domains 1, 2 and 3, respectively. Using the anchoring analysis, the MCIDs were 1.7 points, 1.7 points, and 0.9 points in domains 1, 2 and 3, respectively. The Delphi method required two rounds. In the second round, a consensus was reached that a 2-point change was considered significant in all three domains, but no consensus was reached on a 1-point change. Conclusions By triangulating all three methods, the SF-DEM's MCIDs were 1.9, 2.0 and 1.4 points for domains 1, 2 and 3, respectively. For individuals, these values should be rounded to a 2-point change for each domain.
AB - Objectives Good social functioning is important for people living with dementia and their families. The Social Functioning in Dementia Scale (SF-DEM) is a valid and reliable instrument measuring social functioning in dementia. However the minimum clinically important difference (MCID) has not yet been derived for SF-DEM. This study aims to define the MCID for the SF-DEM. Design We used triangulation, incorporating data from a cross-sectional study to calculate the MCID using distribution-based and anchor-based methods, and a Delphi survey. Setting and participants The cross-sectional survey comprised 299 family carers of people with dementia. Twenty dementia experts (researchers, clinicians, family carers) rated whether changes on clinical vignettes represented a meaningful change in the Delphi survey. Primary outcome measures We calculated the distribution-based MCID as 0.5 of an SD for each of the three SF-DEM domains (1 - spending time with others, 2 - communicating with others, 3 - sensitivity to others). We used the carers' rating of social functioning to calculate the anchor-based MCID. For the Delphi survey, we defined consensus as ≥75% agreement. Where there was lack of consensus, experts were asked to complete a further survey round. Results We found that 0.5 SD of SF-DEM was 1.9 points, 2.2 and 1.4 points in domains 1, 2 and 3, respectively. Using the anchoring analysis, the MCIDs were 1.7 points, 1.7 points, and 0.9 points in domains 1, 2 and 3, respectively. The Delphi method required two rounds. In the second round, a consensus was reached that a 2-point change was considered significant in all three domains, but no consensus was reached on a 1-point change. Conclusions By triangulating all three methods, the SF-DEM's MCIDs were 1.9, 2.0 and 1.4 points for domains 1, 2 and 3, respectively. For individuals, these values should be rounded to a 2-point change for each domain.
KW - delirium & cognitive disorders
KW - dementia
KW - epidemiology
KW - old age psychiatry
UR - https://www.scopus.com/pages/publications/85127287550
UR - https://pearl.plymouth.ac.uk/pms-research/1448/
U2 - 10.1136/bmjopen-2021-058252
DO - 10.1136/bmjopen-2021-058252
M3 - Article
C2 - 35351729
AN - SCOPUS:85127287550
SN - 2044-6055
VL - 12
JO - BMJ Open
JF - BMJ Open
IS - 3
M1 - e058252
ER -