The social functioning in dementia scale (SF-DEM): Exploratory factor analysis and psychometric properties in mild, moderate, and severe dementia

Abstract

Introduction

The psychometric properties of the social functioning in dementia scale over different dementia severities are unknown.

Methods

We interviewed 299 family carers of people with mild, moderate, or severe dementia from two UK research sites; examined acceptability (completion rates); conducted exploratory factor analysis; and tested each factor's internal consistency and construct validity.

Results

Of 299, 285 (95.3%) carers completed questionnaires. Factor analysis indicated three distinct factors with acceptable internal consistency: spending time with other people, correlating with overall social function (r = 0.56, P < .001) and activities of daily living (r = −0.48, P < .001); communicating with other people correlating with activities of daily living (r = −0.66, P < .001); and sensitivity to other people correlating with quality of life (r = 0.35, P < .001) and inversely with neuropsychiatric symptoms (r = −0.45, P < .001). The three factors' correlations with other domains were similar across all dementia severities.

Discussion

The social functioning in dementia scale carer version measures three social functioning domains and has satisfactory psychometric properties in all severities of dementia.