Assessing Alzheimer’s Disease from Speech Using the i-vector Approach

Artificial Intelligence, Speech, and Language Processing Approaches to Monitoring Alzheimer’s Disease: A Systematic Review

“…Other studies attempting 3-way classification experiments in balanced datasets are Egas López et al. [ 62 ], 56% and Gosztolya et al. [ 63 ] with 66.7%.…”

“…SCI can also be named SMC [ 96 ], and there is a similar but different category (AACD) reported in two other studies [ 68, 74 ]. MCI and AD are more homogeneous due to being diagnostic categories that need to meet certain clinical criteria to be assigned, although some studies do refer to AD as dementia [ 62, 95 ]. Another heterogeneous category is CI (i.e., unspecified cognitive impairment), which is annotated as low or high MMSE scores [ 93 ], or as mild dementia [ 89 ].…”

“…Among these 20 studies, one reports only between-class age and gender balance [ 94 ]; another one reports class balance, within-class gender balance, and between-class age and gender balance [ 11 ]. A few report balance for all features except for within-class gender balance, which is not specified [ 62, 63, 88 ]. Lastly, there is only one study that, apart from class balance, also reports gender balance within and between classes, as well as age and education balance between classes [ 87 ].…”

“…Sometimes gender is reported per dataset, but not per class (e.g., [ 92 ]), and therefore not accounted for in the analysis, even though is one of the main risk factors [ 80 ]. Often, p -values are appropriately presented to indicate that demographics are balanced between groups (e.g., [ 62 ]). Unfortunately, almost as often, no statistical values are reported to argue for balance between groups (e.g., [ 83 ]).…”

“…As expected, a number of studies (41%) were conducted through English. However, there is a fair amount of papers using data in a variety of languages, including: Italian [ 91 ], Portuguese [ 57, 90 ], Chinese and Taiwanese [ 82 ], French [ 50, 69, 77, 96, 102 ], Hungarian [ 62, 63, 99 ], Spanish [ 83, 89, 100 ], Swedish [ 7, 59, 87 ], Japanese [ 64, 71, 94 ], Turkish [ 84 ], Persian [ 65 ], Greek [ 61, 88 ], German [ 68, 74 ], or reported as multilingual [ 60, 79, 80 ].…”