The current study provided longitudinal robust norms for individuals age 70 years and older for several neuropsychological tests. We compared baseline neuropsychological test performance in three groups free of dementia at baseline: a robust normative sample free of dementia for at least two post-follow-up assessments, an incident dementia sample which developed new onset dementia during the follow-up and a Lost to Follow-up (LTF) sample. ANCOVAs showed that the robust sample performed better on all neuropsychological tests compared to the incident dementia and LTF samples. These findings support the argument that individuals in transition to developing dementia may reduce the mean, increase the variability and therefore underestimate cognitive performance in normal aging. We suggest that longitudinal robust norms may help mitigate the limitations inherent in cross-sectional normative samples.
Aging; Norms; Dementia; Attrition
The current study provided longitudinal robust norms for individuals age 70 years and older for several neuropsychological tests. We compared baseline neuropsychological test performance in three groups free of dementia at baseline: a robust normative sample free of dementia for at least two post-follow-up assessments, an incident dementia sample which developed new onset dementia during the follow-up and a lost to follow-up (LTF) sample. ANCOVAs showed that the robust sample performed better on all neuropsychological tests compared to the incident dementia and LTF samples. These findings support the argument that individuals in transition to developing dementia may reduce the mean, increase the variability and therefore underestimate cognitive performance in normal aging. We suggest that longitudinal robust norms may help mitigate the limitations inherent in cross-sectional normative samples.
Aging; Norms; Dementia; Attrition
The aim of the current study was to develop and validate demographically-adjusted normative standards for the HIV Dementia Scale (HDS). Given the association between demographic variables and the HDS summary score, demographically-adjusted normative standards may enhance the classification accuracy of the HDS. Demographically-adjusted normative standards were derived from a sample of 182 seronegative healthy participants and were subsequently applied to a sample of 135 HIV-1 seropositive individuals with multidisciplinary case conference diagnoses of HIV-1-associated neurocognitive disorders (e.g., HIV-1-associated dementia and Minor-Cognitive/Motor Disorder) in proportions consistent with published epidemiologic reports. In the normative sample, age and education (and their interaction) emerged as the only demographic factors significantly associated with the HDS. In comparison to the traditional HDS cut score (raw score total ≤10), use of the demographically-adjusted normative standards significantly improved the sensitivity (from 17.2% to 70.7%, respectively) and overall classification accuracy (increasing the odds ratio from 3 to approximately 6) of the HDS for identifying participants with HIV-1-associated neurocognitive disorders. The application of demographically-adjusted normative standards on the HDS improves the clinical applicability and accuracy of this cognitive screening measure in the detection of HIV-1-associated neurocognitive disorders.
Human immunodeficiency virus; Screening Tests; Dementia; Neuropsychological Assessment
While gait is widely used to assess health status in older adults, normative data is lacking. Our objective was to develop and compare norms for widely used gait parameters in adults age 70 and older using cross-sectional (conventional) and longitudinal (robust) approaches accounting for important confounders such as disease effects on gait.
Community-dwelling older adults (age>70, N=824) without dementia or disability
Eight quantitative gait parameters measured using an instrumented walkway.
Of the 824 subjects (conventional normal; CN sample), 304 were included in a ‘robust normal’ (RN) sample after excluding those with either prevalent or incident clinical gait abnormalities developing within one year of the baseline assessment to account for disease effects on gait performance. Descriptively, the RN sample showed better performance on all selected gait variables compared to the CN sample. For instance, mean gait velocity (± standard deviation) was 105.9±17.9 cm/sec in the RN sample compared to 93.3±23.2 cm/sec in the overall CN sample. Applying a one standard deviation below the mean (70.1 cm/sec) derived from CN sample to define slow gait, 15.9% (131) in overall cohort were classified as abnormal whereas the RN cut-off (88.0 cm/sec) classified 39.7% (327) in the overall cohort as abnormal.
Our findings suggest that cross-sectional conventional norms may under-estimate gait performance in aging. Longitudinal robust norms provide more accurate estimates of normal gait performance and thus may improve early detection of gait disorders in older adults.
gait; reference values; elderly
The aim of the study was to compare the performance of Robust and Conventional neuropsychological norms in predicting clinical decline among healthy adults and in mild cognitive impairment (MCI). The authors developed Robust baseline cross sectional and longitudinal change norms from 113 healthy participants retaining a normal diagnosis for at least 4 years. Baseline Conventional norms were separately created for 256 similar healthy participants without follow-up. Conventional and Robust norms were tested in an independent cohort of longitudinally studied healthy (n = 223), MCI (n = 136), and Alzheimer’s disease (AD, n = 162) participants; 84 healthy participants declined to MCI or AD (NL→DEC), and 44 MCI declined to AD (MCI→AD). Compared to Conventional norms, baseline Robust norms correctly identified a higher proportion of NL→DEC with impairment in delayed memory and attention-language domains. Both norms predicted decline from MCI→AD. Change norms for delayed memory and attention-language significantly incremented baseline classification accuracies. These findings indicate that Robust norms improve identification of healthy individuals who will decline and may be useful for selecting at-risk participants for research studies and early interventions.
cognition; longitudinal; normative data; decline from normal; mild cognitive impairment
To extend the psychometric study of the Cognitive Change Checklist (3CL) by examining the reliability, factor structure, and external correlates of 3CL informant and self-report ratings in community dwelling adults. We also conducted ROC analyses examining rating scores from this normative sample with those of clinical samples.
Scale reliability and validity study.
Six hundred and seventy-nine older adults.
The pattern of scale relationships within and across versions, and the failure to find associations with age and education, were consistent with findings in clinic samples reported previously. Factor analysis replicated the four-factor structure of the informant ratings. All informant version scales significantly discriminated amnestic Mild Cognitive Impairment (MCI) cases and patients with mild dementia from normals.
These findings provide support for the use of the checklist as a clinical tool to facilitate identification of cases of MCI and early dementia.
rating scales; informant; activities of daily living; cognition; aging; cognitive decline; mild cognitive impairment; dementia
Normative scores for patient-rated outcome (PRO) instruments are important for providing patient-centered, whole-person care and making informed clinical decisions. Although normative values for the Pediatric Quality of Life Generic Core Scale (PedsQL) have been established in the general, healthy adolescent population, whether adolescent athletes demonstrate similar values is unclear.
To compare PedsQL scores between adolescent athletes and general, healthy adolescent individuals.
Patients or Other Participants:
A convenience sample of 2659 interscholastic athletes (males = 2059, females = 600, age = 15.7 ± 1.1 years) represented the athlete group (ATH), and a previously published normative dataset represented the general, healthy adolescent group (GEN).
All participants completed the PedsQL during 1 testing session.
Main Outcome Measure(s):
The PedsQL consists of 2 summary scores (total, psychosocial) and 4 subscale scores (physical, emotional, social, school), with higher scores indicating better health-related quality of life (HRQOL). Groups were stratified by age (14, 15, or 16 years old). Independent-samples t tests were conducted to compare between-groups and sex differences.
The ATH group scored higher than the GEN group across all ages for total and psychosocial summary scores and for emotional and social functioning subscale scores (P ≤ .005). For physical functioning, scores of the 15-year-old ATH were higher than for their GEN counterparts (P = .001). Both 14- and 15-year-old ATH scored higher than their GEN counterparts for the school functioning subscale (P ≤ .013), but differences between 16-year olds were not significant (P = .228). Male adolescent athletes reported higher scores than female adolescent athletes across all scores (P ≤ .001) except for social functioning (P = .229).
Adolescent athletes reported better HRQOL than GEN, particularly in emotional functioning. These findings further support the notion that ATH constitutes a unique population that requires its own set of normative values for self-reported, patient-rated outcome instruments.
patient outcome assessment; patient-centered care; physical activity
Neuropsychological tests, including tests of language ability, are frequently used to differentiate normal from pathological cognitive aging. However, language can be particularly difficult to assess in a standardized manner in cross-cultural studies and in patients from different educational and cultural backgrounds. This study examined the effects of age, gender, education and race on performance of two language tests, the animal fluency task (AFT) and the Indiana University Token Test (IUTT). We report population-based normative data on these tests from two combined ethnically divergent, cognitively normal, representative population samples of older adults.
Participants aged ≥65 years from the Monongahela-Youghiogheny Healthy Aging Team (MYHAT) and from the Indianapolis Study of Health and Aging (ISHA) were selected based on (1) a Clinical Dementia Rating (CDR) score of 0; (2) non-missing baseline language test data; and (3) race self-reported as African American or white. The combined sample (n=1885) was 28.1 % African American. Multivariate ordinal logistic regression was used to model the effects of demographic characteristics on test scores.
On both language tests, better performance was significantly associated with higher education, younger age, and white race. On the IUTT, better performance was also associated with female gender. We found no significant interactions between age and sex, and between race and education.
Age and education are more potent variables than are race and gender influencing performance on these language tests. Demographically-stratified normative tables for these measures can be used to guide test interpretation and aid clinical diagnosis of impaired cognition.
neuropsychological tests; norms; cognitive aging; verbal fluency; token test
Performance on cognitive tests can be affected by age, education, and also selection bias. We examined the distribution of scores on a several cognitive screening tests by age and educational levels in a population-based cohort.
An age-stratified random sample of individuals aged 65+ years was drawn from the electoral rolls of an urban U.S. community. Those obtaining age and education-corrected scores ≥ 21/30 on the Mini-Mental State Examination were designated as cognitively normal or only mildly impaired, and underwent a full assessment including a battery of neuropsychological tests. Participants were also rated on the Clinical Dementia Rating scale. The distribution of neuropsychological test scores within demographic strata, among those receiving a CDR of 0 (no dementia), are reported here as cognitive test norms. After combining individual test scores into cognitive domain composite scores, multiple linear regression models were used to examine associations of cognitive test performance with age, and education.
In this cognitively normal sample of older adults, younger age and higher education were associated with better performance in all cognitive domains. Age and education together explained 22% of the variation of memory, and less of executive function, language, attention, and visuospatial function.
Older age and lesser education are differentially associated with worse neuropsychological test performance in cognitively normal older adults representative of the community at large. The distribution of scores in these participants can serve as population-based norms for these tests, and be especially useful to clinicians and researchers assessing older adults outside specialty clinic settings.
Neuropsychological tests; epidemiology; normative; community
Individuals age 85 years and above (i.e., the oldest old) represent the fastest growing segment of the U.S. population and are at increased risk of developing dementia. This represents an important challenge for the clinical neuropsychologist, as the extant normative data on neuropsychological measures remains relatively limited for this age group. Therefore, the aim of the present study was to characterize the performance effects of age and education in a large, well-characterized sample of women between the ages of 85 and 95 years on the CVLT-II Short Form (Delis et al., 2000), verbal fluency tasks, and the WAIS-III Digit Span Test (Wechsler, 1997). In order to minimize the likelihood that women with an incipient neurodegenerative process were included in the final normative sample, we applied regression-based change scores to identify and exclude women who evidenced a statistically significant decline on a global cognitive screening measure over a 20 year interval. The results of our analysis indicate varying influence of age and education on these measures and we provide tables with descriptive statistics stratified by both age and education. Findings from the present normative study are discussed within the context of “robust” longitudinal normative data.
oldest old; normative data; CVLT
The Ruff 2&7 Selective Attention Test’s (RSAT) current scoring data are relatively limited for older adults because persons over the age of 70 years were not included in the normative sample. Prior evidence suggests that changes in attention skills, such as those evaluated by the RSAT, may distinguish normal cognitive aging from pathologic cognitive decline. Thus, normative data for older individuals on this measure increases its utility in diagnosing Mild Cognitive Impairment (MCI) and dementia, and enhance its potential use in clinical and research settings. Data from 415 male volunteers (mean age = 69.5 ± 5.7 years) in the PREADViSE clinical trial were used in the current investigation. Analysis of covariance (ANCOVA) shows statistically significant effects of age, race, and education on RSAT Speed measures. Results indicate that age-expanded norms will provide a more accurate reflection of the typical performance of older individuals on the RSAT.
Pictorial stimuli standardized for Chinese children are still absent although it is needed in order to test the development of children's cognitive functions. This study presents normative measures for Snodgrass and Vanderwart pictures, viewed by 4- and 6-year old Chinese children. Name agreement, familiarity, and visual complexity were obtained for each age group. The data indicate substantial differences between young and older children in name agreement based on expected name, familiarity and visual complexity. The correlation pattern of the variables collected in the present study were consistent with children's norms in other languages and norms of Chinese adults, while there are cross-age and cross-culture differences in specific variables. The obtained measures represent a useful tool for further research on Chinese children's pictorial processing and constitute the first picture normative study for children in this language.
Rates of mild cognitive impairment (MCI) have varied substantially, depending on the criteria used and the samples surveyed. The present investigation used a psychometric algorithm for identifying MCI and its’ stability to determine if low cognitive functioning was related to poorer longitudinal outcomes. The Advanced Cognitive Training of Independent and Vital Elders (ACTIVE) study is a multi-site longitudinal investigation of long-term effects of cognitive training with older adults. ACTIVE exclusion criteria eliminated participants at highest risk for dementia (i.e., MMSE<23). Using composite normative for sample- and training- corrected psychometric data, 8.07% of the sample had amnestic impairment, while 25.09% had a non-amnestic impairment at baseline. Poorer baseline functional scores were observed in those with impairment at the first visit, including a higher rate of attrition, depressive symptoms, and self-reported physical functioning. Participants were then classified based upon the stability of their classification. Those who were stably impaired over the five-year interval had the worst functional outcomes (e.g., IADL performance), and inconsistency in classification over time also appeared to be associated increased risk. These findings suggest that there is prognostic value in assessing and tracking cognition to assist in identifying the critical baseline features associated with poorer outcomes.
cognitive impairment; research classification; cognitive aging; longitudinal follow-up
Mild cognitive impairment (MCI) is proposed to be a prodrome to dementia in some older adults. However, the presentation of MCI in the community can differ substantially from clinic-based samples. The aim of the current study is to demonstrate the effects of different operational definitions of MCI on prevalence estimates in community-dwelling older adults. A consecutive series of 200 participants aged 65 and over from the Adult Changes in Thought (ACT) community-based cohort were approached to undergo comprehensive neuropsychological and medical evaluation; 159 were included in the final analyses. Nondemented subjects were categorized using various diagnostic criteria for MCI. In a novel approach, neuropsychological test scores were evaluated using an individualized benchmark as a point of test comparison, as well as traditional methods that entail comparison to age-based normative data. Diagnostic criteria were further subdivided by severity of impairment (1.0 vs. 1.5 standard deviations [sd] below the benchmark) and extent of impairment (based on a single test or an average of tests within a cognitive domain). MCI prevalence rates in the sample were highly dependent on these diagnostic factors, and varied from 11% to 92% of the sample. Older groups tended to show higher prevalence rates, although this was not the case across all diagnostic schemes. The use of an individualized benchmark, less severe impairment cutoff, and impairment on only a single test all produced higher rates of MCI. Longitudinal follow-up will determine whether varying diagnostic criteria improves sensitivity and specificity of the MCI diagnosis as a predictor for dementia.
Age related memory disorders; aging; cognition; Alzheimer's disease; dementia; diagnosis; epidemiology; individual differences; neuropsychological tests; prevalence; normative
Large-scale population studies measuring rates and dynamics of cognitive decline in multiple sclerosis (MS) are lacking. In the current cross-sectional study we evaluated the patterns of cognitive impairment in MS patients with disease duration of up to 30 years.
1,500 patients with MS were assessed by a computerized cognitive battery measuring verbal and non-verbal memory, executive function, visual spatial perception, verbal function, attention, information processing speed and motor skills. Cognitive impairment was defined as below one standard deviation (SD) and severe cognitive impairment as below 2SD for age and education matched healthy population norms.
Cognitive performance in our cohort was poorer than healthy population norms. The most frequently impaired domains were information processing speed and executive function. MS patients with secondary-progressive disease course performed poorly compared with clinically isolated syndrome, relapsing-remitting and primary progressive MS patients. By the fifth year from disease onset, 20.9% of patients performed below the 1SD cutoff for impairment, p = 0.005, and 6.0% performed below the 2SD cutoff for severe cognitive impairment, p = 0.002. By 10 years from onset 29.3% and 9.0% of patients performed below the 1SD and 2SD cutoffs, respectively, p = 0.0001. Regression modeling suggested that cognitive impairment may precede MS onset by 1.2 years.
The rates of cognitive impairment in this large sample of MS patients were lower than previously reported and severe cognitive impairment was evident only in a relatively small group of patients. Cognitive impairment differed significantly from expected normal distribution only at five years from onset, suggesting the existence of a therapeutic window during which patients may benefit from interventions to maintain cognitive health.
The large number of primary Spanish speakers both in the United States and the world makes it imperative that appropriate neuropsychological assessment instruments be available to serve the needs of these populations. In this article we describe the norming process for Spanish speakers from the U.S.–Mexico border region on the Brief Visuospatial Memory Test-revised and the Hopkins Verbal Learning Test-revised. We computed the rates of impairment that would be obtained by applying the original published norms for these tests to raw scores from the normative sample, and found substantial overestimates compared to expected rates. As expected, these overestimates were most salient at the lowest levels of education, given the under-representation of poorly educated subjects in the original normative samples. Results suggest that demographically corrected norms derived from healthy Spanish-speaking adults with a broad range of education, are less likely to result in diagnostic errors. At minimum, demographic corrections for the tests in question should include the influence of literacy or education, in addition to the traditional adjustments for age. Because the age range of our sample was limited, the norms presented should not be applied to elderly populations.
Cross-cultural assessment; Spanish; Hispanic; Learning; Memory; Ethnic differences
Scores on the Boston Naming Test (BNT) are frequently lower for African American when compared to Caucasian adults. Although demographically-based norms can mitigate the impact of this discrepancy on the likelihood of erroneous diagnostic impressions, a growing consensus suggests that group norms do not sufficiently address or advance our understanding of the underlying psychometric and sociocultural factors that lead to between-group score discrepancies. Using item response theory and methods to detect differential item functioning (DIF), the current investigation moves beyond comparisons of the summed total score to examine whether the conditional probability of responding correctly to individual BNT items differs between African American and Caucasian adults. Participants included 670 adults age 52 and older who took part in Mayo's Older Americans and Older African Americans Normative Studies. Under a 2-parameter logistic IRT framework and after correction for the false discovery rate, 12 items where shown to demonstrate DIF. Six of these 12 items (“dominoes,” “escalator,” “muzzle,” “latch,” “tripod,” and “palette”) were also identified in additional analyses using hierarchical logistic regression models and represent the strongest evidence for race/ethnicity-based DIF. These findings afford a finer characterization of the psychometric properties of the BNT and expand our understanding of between-group performance.
Boston Naming Test; Item response theory; Differential item functioning; Ethnicity; Race; Bias
Dementia is a cause of disability in later life. Despite the importance of functional status to the diagnosis of dementia, limited information exists on differences in functional limitations by dementia subtype. We conducted a cross-sectional analysis using the Aging, Demographics, and Memory Study (ADAMS) to determine the extent of functional impairment among older adults with dementia due to different etiologies.
The ADAMS sample consisted of 856 individuals aged 71 years and older originally surveyed as part of the Health and Retirement Study. Based on a comprehensive in-person cognitive evaluation, respondents were assigned to diagnostic categories of normal cognition, cognitive impairment not demented, and demented. Dementia subtypes were grouped into three categories: vascular dementia (VaD), Alzheimer’s dementia (AD), and dementia due to other etiologies. For 744 of the 856 respondents, a proxy informant completed a questionnaire asking whether the respondent had difficulty completing instrumental activities of daily living and activities of daily living (ADLs).
Of 744 ADAMS participants, 263 had dementia: 199 (70.5%) with AD, 42 (16.9%) with VaD, and 22 (12.6%) were demented due to other etiologies. After adjustment for demographics, chronic illnesses, and dementia severity, participants with VaD (odds ratio [OR] 5.74; 95% confidence interval [CI] 2.60–12.69) and other etiologies of dementia (OR 21.23; 95% CI 7.25–62.16) were more likely to have greater than or equal to four ADL limitations compared with those with AD.
VaD is associated with significantly more ADL limitations than AD. These physical limitations should be considered when designing adult day care programs, which adequately accommodate the needs of non-AD patients.
Activities of daily living; Instrumental activities of daily living; Disability; Dementia
The two objectives of this study were (a) to replicate the previous finding of more severe sleep difficulties in a sample of individuals with spinal cord injury (SCI) compared with normative samples, and (b) to examine the associations between aging variables (specifically, chronological age, duration of SCI, age at SCI onset) and the severity of sleep difficulties.
A survey was administered to 620 individuals with SCI that included measures of demographic characteristics and sleep difficulties.
The findings indicated that sleep problems are more common in individuals with SCI than in normative samples. In addition, younger participants in our sample reported more sleep problems than did older participants. Duration of SCI and age at onset, however, were not significantly associated with sleep difficulties.
The analyses used in this study provide a model for examining age effects using concurrent survey data that may be useful for other investigators interested in studying the associations between age-related variables and important health-related domains.
spinal cord injury; sleep problems; aging; multiple regression
Determining mobility status is an important component of any health assessment for older adults. In order for a mobility measure to be relevant and meaningful, normative data are required for comparison to a healthy reference population. The DEMMI is the first mobility instrument to measure mobility across the spectrum from bed bound to functional levels of independent mobility. In this cross-sectional observational study, normative data were obtained for the DEMMI from a population of 183 healthy, community-dwelling adults age 60+ who resided in Vancouver, Canada and Melbourne, Australia. Older age categories had significantly lower DEMMI mobility mean scores (P < 0.05), as did individuals who walked with a mobility aid or lived in semi-independent living (assisted living or retirement village), whereas DEMMI scores did not differ by sex (P = 0.49) or reported falls history (P = 0.21). Normative data for the DEMMI mobility instrument provides vital reference scores to facilitate its use across the mobility spectrum in clinical, research, and policymaking settings.
The CLOX is a clock drawing test used to screen for cognitive impairment in older adults, but there is limited normative data for this measure. This study presents normative data for the CLOX derived from a diverse sample of 585 community-dwelling older adults with complete cognitive data at baseline and 4-year follow-up. Participants with evidence of baseline impairment or substantial 4-year decline on the Mini-Mental State Examination were excluded from the normative sample. Spontaneous clock drawing (CLOX1) and copy (CLOX2) performances were stratified by age group and reading ability from the Wide Range Achievement Test, 3rd edition (WRAT-3). Lowest mean CLOX scores were observed for the oldest age group (75+ years old) with the lowest WRAT-3 reading scores. For all groups, average scores were higher for CLOX2 than CLOX1. These normative data may be helpful to clinicians and researchers for interpreting CLOX performance in older adults with diverse levels of reading ability.
Normative data; Clock drawing test; Reading ability; Older adults; Aging
The objective was to examine various aspects of narcissism in patients admitted to acute psychiatric wards and to compare their level of narcissism to that of an age- and gender-matched sample from the general population (NORM).
This cross-sectional study interviewed 186 eligible acute psychiatric patients with the Brief Psychiatric Rating Scale (BPRS) and the Global Assessment of Functioning (GAF). The patients filled in the Narcissistic Personality Inventory-21 item version (NPI-21), The Hospital Anxiety and Depression Scale (HADS) and the Rosenberg Self-Esteem Scale. High and low narcissism was defined by the median of the total NPI-21 score. An age- and gender-matched control sample from the general population also scored the NPI-21 (NORM).
Being male, involuntary admitted, having diagnosis of schizophrenia, higher self-esteem, and severe violence were significantly associated with high narcissism, and so were also low levels of suicidality, depression, anxiety and GAF scores. Severe violence and high self-esteem were significantly associated with high narcissism in multivariable analyses. The NPI-21 and its subscales showed test-retest correlations ≥0.83, while the BPRS and the HADS showed lower correlations, confirming the trait character of the NPI-21. Depression and suicidality were negatively associated with the NPI-21 total score and all its subscales, while positive association was observed with grandiosity. No significant differences were observed between patients and NORM on the NPI-21 total score or any of the NPI subscales.
Narcissism in the psychiatric patients was significantly associated with violence, suicidality and other symptoms relevant for management and treatment planning. Due to its trait character, use of the NPI-21 in acute psychiatric patients can give important clinical information. The similar level of narcissism found in patients and NORM is in need of further examination.
A key component of successful aging in old age is the ability to independently perform instrumental activities of daily living (IADLs). We examined the ability to perform multiple IADL tasks in relation to mild cognitive impairment (MCI) defined on purely neuropsychological grounds.
Population-based cohort in Southwestern Pennsylvania.
1,737 community-dwelling adults aged 65 years and older.
Classification of MCI based on performance with reference to norms in the cognitive domains of memory, language, attention, executive and visuospatial function. The ability to perform seven IADL tasks (travel, shopping, meal preparation, housework, taking medications, handling personal finances, and telephone use) as assessed by the Older Americans Resources and Services (OARS) scale.
Those with cognitively defined MCI were more likely to be dependent in at least one IADL task, and in each individual IADL task, than cognitively normal participants. Better memory and executive functioning were associated with lower odds of IADL dependence in MCI. Across the subtypes of MCI, those with the multiple-domain amnestic subtype were the most likely to be dependent in all IADL tasks; with better executive functioning associated with lower risk of dependence in select IADL tasks in this group.
Mild impairment in cognition is associated with difficulty performing IADL tasks at the population level. Understanding these associations may help improve prediction of the outcomes of MCI. It may also allow appropriate targeting of cognitive interventions in MCI to potentially help preserve functional independence.
cognition; mild cognitive impairment; everyday functioning; instrumental activities of daily living; epidemiology; community; population
Gait performance is widely evaluated to assess health status in older adult populations. While several investigators have presented normative values for spatiotemporal gait parameters drawn from older adult populations, the literature has been void of large-scale cohort studies, which are needed in order to provide quantitative, normative gait data in persons with Parkinson’s disease. The aim of this investigation was to provide reference values for clinically important gait characteristics in a large sample of ambulatory persons with Parkinson’s disease to aid both clinicians and researchers in their evaluations and treatments of gait impairment.
Gait performance was collected in 310 individuals with idiopathic Parkinson’s disease as they walked across a pressure sensitive walkway. Fourteen quantitative gait parameters were measured and evaluated with respect to Hoehn and Yahr disease staging and gender. Disease duration and age were controlled for in all analyses. Individuals with the greatest Parkinson’s disability walked significantly slower with shorter steps and stride lengths than the mild and moderately affected groups. Further, the most affected patients spent more time with both feet on the ground, and walked with a wider base of support than the moderately disabled patients. No differences were detected between the mild and moderate disability groups on any of the gait parameters evaluated.
Reference values for 14 gait parameters in a large cohort of ambulatory patients with Parkinson’s disease are provided and these may be highly useful for assessing and interpreting an individual’s gait dysfunction. It is important for clinicians and researchers to appreciate the lack of change in quantitative parameters as PD patients move from mild to moderate gait impairment.
Previous research has shown that students overestimate the drinking of their peers, and that perceived norms are strongly associated with drinking behavior. Explanations for these findings have been based largely on cross-sectional data, precluding the ability to evaluate the stability of normative misperceptions or to disentangle the direction of influence between perceived norms and drinking. The present research was designed to evaluate (1) the stability of normative misperceptions and (2) temporal precedence of perceived norms and drinking.
Participants were college students (N = 164; 94 women) who completed assessments of perceived norms and reported behavior for drinking frequency and weekly quantity. Most participants (68%) completed the same measures again two months later.
Results indicated large and stable overestimations of peer drinking for frequency and weekly quantity. Results also showed that for weekly quantity, perceived norms predicted later drinking, but drinking also predicted later perceived norms. Results for frequency revealed perceived norms predicted later drinking, but drinking did not predict later perceived norms.
These findings underscore the importance of longitudinal designs in evaluating normative influences on drinking. The present findings suggest that normative misperceptions are stable, at least over a relatively short time period. Findings support a mutual influence model of the relationship between perceived norms and drinking quantity but are more strongly associated with conformity explanations for the relationship between perceived norms and drinking frequency. Results are discussed in terms of implications for prevention interventions.