Adam C. Carle

Development and assessment of a composite score for memory in the Alzheimer’s Disease Neuroimaging Initiative (ADNI)

We sought to develop and evaluate a composite memory score from the neuropsychological battery used in the Alzheimer’s Disease (AD) Neuroimaging Initiative (ADNI). We used modern psychometric approaches to analyze longitudinal Rey Auditory Verbal Learning Test (RAVLT, 2 versions), AD Assessment Schedule - Cognition (ADAS-Cog, 3 versions), Mini-Mental State Examination (MMSE), and Logical Memory data to develop ADNI-Mem, a composite memory score. We compared RAVLT and ADAS-Cog versions, and compared ADNI-Mem to RAVLT recall sum scores, four ADAS-Cog-derived scores, the MMSE, and the Clinical Dementia Rating Sum of Boxes. We evaluated rates of decline in normal cognition, mild cognitive impairment (MCI), and AD, ability to predict conversion from MCI to AD, strength of association with selected imaging parameters, and ability to differentiate rates of decline between participants with and without AD cerebrospinal fluid (CSF) signatures. The second version of the RAVLT was harder than the first. The ADAS-Cog versions were of similar difficulty. ADNI-Mem was slightly better at detecting change than total RAVLT recall scores. It was as good as or better than all of the other scores at predicting conversion from MCI to AD. It was associated with all our selected imaging parameters for people with MCI and AD. Participants with MCI with an AD CSF signature had somewhat more rapid decline than did those without. This paper illustrates appropriate methods for addressing the different versions of word lists, and demonstrates the additional power to be gleaned with a psychometrically sound composite memory score.

A composite score for executive functioning, validated in Alzheimer’s Disease Neuroimaging Initiative (ADNI) participants with baseline mild cognitive impairment

The Alzheimer’s Disease Neuroimaging Initiative (ADNI) measures abilities broadly related to executive function (EF), including WAIS-R Digit Symbol Substitution, Digit Span Backwards, Trails A and B, Category Fluency, and Clock Drawing. This study investigates whether a composite executive function measure based on these multiple indicators has better psychometric characteristics than the widely used individual components. We applied item response theory methods to 800 ADNI participants to derive an EF composite score (ADNI-EF) from the above measures. We then compared ADNI-EF with component measures in 390 longitudinally-followed participants with mild cognitive impairment (MCI) with respect to: (1) Ability to detect change over time; (2) Ability to predict conversion to dementia; (3) Strength of cross-sectional association with MRI-derived measures of structures involved in frontal systems, and (4) Strength of baseline association with cerebrospinal fluid (CSF) levels of amyloid β1-42, total tau, and phosphorylated tau181P. ADNI-EF showed the greatest change over time, followed closely by Category Fluency. ADNI-EF needed a 40xa0% smaller sample size to detect change. ADNI-EF was the strongest predictor of AD conversion. ADNI-EF was the only measure significantly associated with all the MRI regions, though other measures were more strongly associated in a few of the regions. ADNI-EF was associated with all the CSF measures. ADNI-EF appears to be a useful composite measure of EF in MCI, as good as or better than any of its composite parts. This study demonstrates an approach to developing a psychometrically sophisticated composite score from commonly-used tests.

Socioeconomic Status, Food Security, and Dental Caries in US Children: Mediation Analyses of Data From the National Health and Nutrition Examination Survey, 2007-2008

OBJECTIVESnWe examined associations of household socioeconomic status (SES) and food security with childrens oral health outcomes.nnnMETHODSnWe analyzed 2007 and 2008 US National Health and Nutrition Examination Survey data for children aged 5 to 17 years (nu2009=u20092206) to examine the relationship between food security and untreated dental caries and to assess whether food security mediates the SES-caries relationship.nnnRESULTSnAbout 20.1% of children had untreated caries. Most households had full food security (62%); 13% had marginal, 17% had low, and 8% had very low food security. Higher SES was associated with significantly lower caries prevalence (prevalence ratio [PR]u2009=u20090.77; 95% confidence intervalu2009=u20090.63, 0.94; Pu2009=u2009.01). Children from households with low or very low food security had significantly higher caries prevalence (PRu2009=u20092.00 and PRu2009=u20091.70, respectively) than did children living in fully food-secure households. Caries prevalence did not differ among children from fully and marginally food-secure households (Pu2009=u2009.17). Food insecurity did not appear to mediate the SES-caries relationship.nnnCONCLUSIONSnInterventions and policies to ensure food security may help address the US pediatric caries epidemic.

Racial/Ethnic Variation in Breastfeeding Across the US: A Multilevel Analysis from the National Survey of Children’s Health, 2007

We examined whether differences across states in race/ethnicity-specific breastfeeding rates are due solely to state differences in individual factors associated with breastfeeding or additionally, certain state “contextual” factors. Using data from the 2007 National Survey of Children’s Health, multilevel models examined whether state variability in race/ethnicity specific breastfeeding initiation and duration to 6xa0months were explained by (1) individual sociodemographic characteristics of women in states, and (2) an aggregate state measure of the availability of evidence-based maternity care services related to breastfeeding. Observed variability of race/ethnicity-specific breastfeeding rates was only minimally reduced after adjusting for sociodemographic characteristics (Median Odds Ratios (MOR), breastfeeding initiation: non-Hispanic Whitexa0=xa01.46, non-Hispanic Blackxa0=xa02.26; Hispanicxa0=xa01.89. MOR, breastfeeding for 6xa0months: non-Hispanic Whitexa0=xa01.36, non-Hispanic Blackxa0=xa01.84; Hispanicxa0=xa01.56). Overall variability in the degree of state gaps changed little in adjusted models (breastfeeding initiation: non-Hispanic Black σ2xa0=xa00.74, se 0.28, Hispanic σ2xa0=xa00.45, se 0.11; breastfeeding to 6-months: non-Hispanic Black σ2xa0=xa00.41, se 0.10, Hispanic σ2xa0=xa00.22, se 0.05). The measure of maternity care services was positively associated with breastfeeding overall but generally did not explain a substantial portion of between-state variability nor the overall variability in racial/ethnic gaps. Contextual sources of variation in state breastfeeding practices and disparities remain poorly understood. Differences in the socioeconomic makeup of states do not fully explain variability. The association of state breastfeeding rates and disparities with relevant policy and practice factors should be further investigated.

Limited impact on health and access to care for 19- to 25-year-olds following the Patient Protection and Affordable Care Act.

IMPORTANCEnThe Patient Protection and Affordable Care Act (PPACA) allowed young adults to remain on their parents insurance until 26 years of age. Reports indicate that this has expanded health coverage.nnnOBJECTIVEnTo evaluate coverage, access to care, and health care use among 19- to 25-year-olds compared with 26- to 34-year-olds following PPACA implementation.nnnDESIGN, SETTING, AND PARTICIPANTSnData from the Behavior Risk Factor Surveillance System and the National Health Interview Survey, which provide nationally representative measures of coverage, access to care, and health care use, were used to conduct the study among participants aged 19 to 25 years (young adults) and 26 to 34 years (adults) in 2009 and 2012.nnnEXPOSUREnSelf-reported health insurance coverage.nnnMAIN OUTCOMES AND MEASURESnHealth status, presence of a usual source of care, and ability to afford medications, dental care, or physician visits.nnnRESULTSnHealth coverage increased between 2009 and 2012 for 19- to 25-year-olds (68.3% to 71.7%). Using a difference-in-differences (DID) approach, after adjustment, the likelihood of having a usual source of care decreased in both groups but more significantly for 26- to 34-year-olds (DID, 2.8%; 95% CI, 0.45 to 5.15). There was no significant change in health status for 19- to 25-year-olds compared with 26- to 34-year-olds (DID, -0.5%; 95% CI, -1.87 to 0.87). There was no significant change for 19- to 25-year-olds compared with 26- to 34-year-olds in the percentage who reported receiving a routine checkup in the past year (DID, 0.3%; 95% CI, -2.25 to 2.85) or in the ability to afford prescription medications (DID, -0.4%; 95% CI, -2.93 to 1.93), dental care (DID, -2.6%; 95% CI, -5.61 to 0.61), or physician visits (DID, -1.7%; 95% CI, -3.66 to 0.26). There was also no change in the percentage who reported receiving a flu shot (DID, 1.9; 95% CI, -1.93 to 4.93). Insured individuals were more likely to report having a usual source of care and a recent routine checkup and were more likely to be able to afford health care than uninsured individuals.nnnCONCLUSIONS AND RELEVANCEnImplementation of the PPACA was associated with increased health insurance coverage for 19- to 25-year-olds without significant changes in perceived health care affordability or health status. Although the likelihood of having a usual source of care declined between 2009 and 2012 for all, this decrease was smaller among 19- to 25-year-olds, and younger adults were more likely than 26- to 34-year-olds to have a usual source of care.

Advancing PROMIS's methodology: results of the Third Patient-Reported Outcomes Measurement Information System (PROMIS(®)) Psychometric Summit.

In 2002, the NIH launched the ‘Roadmap for Medical Research’. The Patient-Reported Outcomes Measurement Information System (PROMIS®) is one of the Roadmap’s key aspects. To create the next generation of patient-reported outcome measures, PROMIS utilizes item response theory (IRT) and computerized adaptive testing. In 2009, the NIH funded the second wave of PROMIS studies (PROMIS II). PROMIS II studies continue PROMIS’s agenda, but also include new features, including longitudinal analyses and more sociodemographically diverse samples. PROMIS II also includes increased emphasis on pediatric populations and evaluation of PROMIS item banks for clinical research and population science. These aspects bring new psychometric challenges. To address this, investigators associated with PROMIS gathered at the Third Psychometric Summit in September 2010 to identify, describe and discuss pressing psychometric issues and new developments in the field, as well as make analytic recommendations for PROMIS. The summit addressed five general themes: linking, differential item functioning, dimensionality, IRT models for longitudinal applications and new IRT software. In this article, we review the discussions and presentations that occurred at the Third PROMIS Psychometric Summit.

Caregiver Burden and Preventive Dental Care Use for US Children with Special Health Care Needs: A Stratified Analysis Based on Functional Limitation

AbstractnThe objectives of this study were to evaluate the association between caregiver burden and preventive dental care use for children with special health care needs (CSHCN) and assess if caregiver burden explains the relationship between child- and family-level characteristics and preventive dental care use. Samples of US CSHCN ages 3–17xa0years with a functional limitation (nxa0=xa07,559) and those without (nxa0=xa026,345) were derived from the 2005–2006 National Survey of CSHCN. We generated structural equation models, stratified by functional limitation, to describe the relationships between caregiver burden and preventive dental utilization. We measured caregiver burden using six items on whether the child’s health condition impacted work, time spent on health management, and finances. About 80.9xa0% of CSHCN used preventive dental care. Higher levels of caregiver burden were associated with significantly lower odds of preventive dental care use for CHSCN with a functional limitation (βxa0=xa0−0.06; Pxa0<xa00.001) and those without (βxa0=xa0−0.07; Pxa0<xa00.001). For CSHCN with a functional limitation, family poverty and being uninsured were significantly associated with greater caregiver burden and less preventive dental use. Findings were similar for CSHCN without a functional limitation, except that lower caregiver education was also associated with greater caregiver burden and less preventive dental care use. Caregiver burden is potential barrier to preventive dental care use for CSHCN and explains the relationship between child- and family-level characteristics and preventive dental care use. Interventions to improve the oral health of CSHCN should include strategies to reduce caregiver burden, especially within socioeconomically vulnerable families.

Confirmatory Factor Analysis of the Patient Reported Outcomes Measurement Information System (PROMIS) Adult Domain Framework Using Item Response Theory Scores.

Background:To guide measure development, National Institutes of Health-supported Patient reported Outcomes Measurement Information System (PROMIS) investigators developed a hierarchical domain framework. The framework specifies health domains at multiple levels. The initial PROMIS domain framework specified that physical function and symptoms such as Pain and Fatigue indicate Physical Health (PH); Depression, Anxiety, and Anger indicate Mental Health (MH); and Social Role Performance and Social Satisfaction indicate Social Health (SH). We used confirmatory factor analyses to evaluate the fit of the hypothesized framework to data collected from a large sample. Methods:We used data (n=14,098) from PROMIS’s wave 1 field test and estimated domain scores using the PROMIS item response theory parameters. We then used confirmatory factor analyses to test whether the domains corresponded to the PROMIS domain framework as expected. Results:A model corresponding to the domain framework did not provide ideal fit [root mean square error of approximation (RMSEA)=0.13; comparative fit index (CFI)=0.92; Tucker Lewis Index (TLI)=0.88; standardized root mean square residual (SRMR)=0.09]. On the basis of modification indices and exploratory factor analyses, we allowed Fatigue to load on both PH and MH. This model fit the data acceptably (RMSEA=0.08; CFI=0.97; TLI=0.96; SRMR=0.03). Discussion:Our findings generally support the PROMIS domain framework. Allowing Fatigue to load on both PH and MH improved fit considerably.

Child- and state-level characteristics associated with preventive dental care access among U.S. children 5-17 years of age.

The objectives of this study is to identify factors associated with lack of preventive dental care among U.S. children and state-level factors that explain variation in preventive dental care access across states. We performed bivariate analyses and multilevel regression analyses among 68,350 children aged 5–17xa0years using the 2007 National Survey of Children’s Health data and relevant state-level data. Odds ratios (ORs) for child- and state-level variables were calculated to estimate associations with preventive dental care. We calculated interval odds ratios (IOR), median odds ratios (MOR), and intraclass correlation coefficients (ICC) to quantify variation in preventive dental care across states. Lack of preventive dental care was associated with various child-level factors. For state-level factors, a higher odds of lack of preventive dental care was associated with a higher percentage of Medicaid-enrolled children not receiving dental services (ORxa0=xa01.30, 95xa0% confidence interval (CI): 1.15–1.47); higher percentage of children uninsured (ORxa0=xa01.48, 95xa0% CI: 1.29–1.69); lower dentist-to-population ratio (ORxa0=xa01.36, 95xa0% CI: 1.03–1.80); and lower percentage of dentists submitting Medicaid/State Children’s Health Insurance Program claims (ORxa0=xa01.04, 95xa0% CI: 1.01–1.06). IORs for the first three state-level factors did not contain one, indicating that these state-level characteristics were important in understanding variation across states. Lack of preventive dental care varied by state (MORxa0=xa01.40). The state-level variation (ICCxa0=xa03.66xa0%) accounted for a small percentage of child- and state-level variation combined. Child- and state-level characteristics were associated with preventive dental care access among U.S. children aged 5–17xa0years. State-level factors contribute to variation in dental care access across states and need to be considered in state-level planning.

Maternal Correlates of Children's Stress Functioning Following a Major Natural Disaster

Concordant assessments of psychological functioning, salivary alpha-amylase (sAA), and cortisol activity were taken for children (n = 28, 6–10 yrs) and their mothers two months after being displaced by Hurricane Katrina and living in a relocation camp. Multilevel regression models revealed that the psychological functioning of the displaced children did not differ from that of demographically matched controls (n = 19 children), but the displaced group had higher sAA activity and lower cortisol levels. Compared to control mothers, displaced mothers showed higher sAA activity; greater symptoms of depression, distress, and anxiety; and lower self-esteem. Maternal psychological functioning was related to children’s endocrine activity. The results suggest that pervasive stress exposure may be associated with unique psychobiological distress regulation for mother-child dyads.