Correlations between the radio and X-ray bands in the hard state of black hole X-ray binaries (BHBs) have led to the discovery of the Fundamental Plane of black hole accretion, linking accretion-driven radiative attributes to black hole mass. Although this discovery has led to new constraints on radiative efficiencies, there is still significant degeneracy in terms of understanding the governing physics. I present several new results exploring the processes driving the Fundamental Plane over the black hole mass range. These include the first ever homogeneous fits of sources at approximately the same Eddington luminosity but millions of times different in mass, which I focus on for this proceeding article.

Education is correlated with cognitive status assessment. Concern for test bias has led to questions of equivalent construct validity across education groups. Following the work of previous researchers, we submitted Mini-Mental State Examination (MMSE) responses to external validation analyses. Subjects were older participants in the Epidemiologic Catchment Area study (age 50-98). Little evidence for test bias against those with low education was found. The correlation of MMSE scores and age was equivalent across high-and low-education groups (−.29 vs. −.27, p = .48), as was the correlation of MMSE scores and activities of daily living (ADL) functioning (−.23 vs. −.27, p = .42). The MMSE displayed significantly higher internal consistency reliability in the low-education group (.75 vs .72, p = .04). The MMSE did not predict functional decline over 1 year or mortality over 13 years differently by level of educational attainment. Evidence for sex bias was found. The MMSE was more highly correlated with age among women than among men (−.28 vs. −.21, p < .001). The MMSE was more highly correlated with ADL impairment among women than among men (−.30 vs. −.17, p = .01). The MMSE predicted mortality differently according to participant sex (p = 0.53). The lack of evidence for bias provides little support to proposals to adjust MMSE scores according to level of education.

Background. Little work has been published on the internal structure of the Mini-Mental State Examination (MMSE), one of the most widely used instruments for grading cognitive status in clinical settings and field research.

Methods. MMSE responses from a sample of older adults (50–98 years) in five US sites (N = 8556) were analysed.

Results. A five-factor solution was found to be most appropriate. The first factor (concentration) had large loadings with serial sevens and spell world backwards items. The second factor (language and praxis) had large loadings with naming, follow command and praxis items. The third factor (orientation) had loadings with orientation to time and place items. The fourth factor (memory) had large loadings with delayed recall items and the fifth (attention) had large loadings with immediate registration items.

Conclusions. We found that the MMSE is essentially unidimensional; nevertheless, evidence was revealed suggesting that the MMSE is a multidimensional assessment instrument. Dimensions revealed in this sample correspond directly to MMSE sections articulated by the developers of the instrument. These findings have not been reported in previous factor analyses of the MMSE. The findings support the construct validity of the MMSE as a measure of cognitive mental state among community dwelling older adults.