Table 3.
Validation studies assessing the psychometric properties of the DS
| Study | Population | n | Outcome |
|---|---|---|---|
| Stern et al. 1994 [3]: Predictors I study | Mild–moderate AD | 249 | Inter-rater reliability (interclass correlation), 0.99 for total score; internal consistency (Cronbach’s α), 0.66; significant correlation with CDR (r = 0.34) and mMMS (r = − 0.27) |
| Lenderking et al. 2013 [10]: Predictors I + II studies | Mild-moderate AD | 460 | Internal consistency (Cronbach’s α), 0.72; construct validity, correlation with BDRS (r = 0.60), mMMS (r = − 0.30) |
| Lenderking et al. 2013 [10]; DADE Study | Mild-moderate AD | 172 | Internal consistency (Cronbach’s α), 0.72; construct validity, significant correlation with MMSE (r = − 0.47), CDR-SB (r = − 0.64), DAD (r = − 0.72), and NPI (r = 0.21) |
| Lenderking et al. 2013 [10]: ELN-AIP 901 study | Mild-moderate AD | 166 | Internal consistency (Cronbach’s α), 0.74; construct validity, significant correlation with MMSE (r = − 0.53), ADAS-cog (r = − 0.42), DAD (r = − 0.77), and NPI (r = 0.51) |
| Wyrwich et al. 2014 [13] | Mild-moderate AD | 2334 | Internal consistency (Cronbach’s α), 0.66; construct validity, significant correlation with ADAS-cog (r = 0.36), MMSE (r = − 0.34), DAD (r = − 0.63), CDR-SB (r = 0.61), and NPI (r = 0.32); responsiveness, significant correlation with change scores on ADAS-cog, DAD, CDR-SB, and MMSE (baseline to week 78) |
| Brickman et al. 2002 [18]: Predictors 1 study | Mild-moderate AD | 230 | Statistically significant change in total DS score over time (0.5 points per 6 month interval) (p < 0.001). |
| Garre-Olmo et al. 2015 [14]: CoDep AD study* | Mild-severe AD | 343 | Internal consistency (Cronbach’s α), 0.85; significant correlation with DAD score (r = 0.900), CBI (r = 0.323), NPI (r = 0.374), and MMSE (r = 0.617) |
CDR clinical dementia rating, MMSE Mini Mental State Examination, mMMS modified MMSE, BDRS blessed dementia rating scale, CDR-SB Clinical Dementia Rating Scale Sum of Boxes, DAD disability assessment for dementia, ADAS-cog Alzheimer’s Disease Assessment Scale-cognitive subscale, NPI neuropsychiatric inventory, CBI caregiver burden interview. *Spanish translation of DS