Relative age effects in the Movement Assessment Battery for Children-2: age banding and scoring errors.

AIM: The Movement Assessment Battery for Children-2 (MABC-2) uses age-grouped scoring, which will result in relative motor functioning being overestimated for some children and underestimated for others. In this paper, we measure these errors and discuss their consequences. METHOD: We pool data from two validation studies to obtain a sample of 278 children assessed with the MABC-2 (mean (SD) age: 5 years, 0 months (9.6 months); 142 female). We used regression to measure the association between standard score and relative age, and used these results to estimate misclassification rates at the MABC-2's recommended thresholds. RESULTS: Movement Assessment Battery for Children-2 scores were distributed as expected (mean (SD) = 10.4 (2.8)). We estimated that the standard score varied by 2.76 units (0.92 SDs) per year of relative age. Depending on threshold and age bandwidth, this implies overall misclassification rates from 9% to 23%. INTERPRETATION: Relative age differences in MABC-2 scores led to substantial systematic error for young children. These errors can affect MABC-2 validity, longitudinal stability and agreement with other tools, which may reduce the appropriateness of care offered to children. Scoring approaches that may reduce or eliminate these errors are outlined.

Comparing probable case identification of developmental coordination disorder using the short form of the Bruininks-Oseretsky Test of Motor Proficiency and the Movement ABC.

Aim Despite its widespread current use in research and its potential for future application, the validity of the short form of the Bruininks-Oseretsky Test of Motor Proficiency (BOTMP-SF) when administered by trained lay assessors is not known. This paper reports the results of case identification using the Movement Assessment Battery for Children (M-ABC) in a group of children scoring below the sixth percentile on the BOTMP-SF. Methods The BOTMP-SF was administered by trained research assistants to 2058 children. In total, 24 of 128 children aged 10 (n = 10), 11 (n = 10) or 12 (n = 4) scoring below the sixth percentile were randomly selected for further assessment by a paediatric occupational therapist using the M-ABC and the Kaufman Brief Intelligence Test. Results Twenty-one of 24 children positive for motor co-ordination problems on the BOTMP-SF scored below the 15th percentile of the M-ABC, a positive predictive value (PPV) of 0.88 [95% confidence interval (CI) = 0.69 to 0.96]. Fifteen of these children were below the fifth percentile (PPV = 0.63; 95% CI = 0.43 to 0.79). Conclusions The BOTMP-SF seems to be a reasonable alternative to case identification when clinical assessment with the M-ABC is not feasible. Further research is needed to examine the sensitivity and specificity of the short form when used for this purpose.

Contingent vulnerability of entorhinal parvalbumin-containing neurons in Alzheimer's disease.

Calcium-binding proteins containing local circuit neurons are distributed ubiquitously in the human cerebral cortex where they colocalize with a subpopulation of cells that contain GABA. Several reports using a variety of pathological models, including Alzheimer's disease (AD), have suggested that cells containing calcium-binding proteins are resistant to pathological insults. In this report, we test the hypothesis that AD pathology can differentially affect parvalbumin-containing cells depending on their location in the entorhinal cortex and the state of projection neurons with which they are associated. Using cases with different quantities of AD pathology, we determined the density of immunostaining for parvalbumin in the entorhinal cortex, and we correlated this with the concomitant pathological lesions in the various layers of this cortex. Our results show a clear decrease in parvalbumin immunostaining in some parts of the entorhinal cortex when AD neuropathological markers are present. As the density of pathological markers in the entorhinal cortex becomes greater and more widespread, there is a decrease of parvalbumin immunostaining in additional layers, although in all cases, some cells persist. Parvalbumin-containing neurons are clearly vulnerable in AD, but not because of neurofibrillary tangle formation. Instead, they are rendered vulnerable only after substantial loss of projection neurons; only then do they, too, become part of the lesion.