Adjusting for Measurement Noninvariance with Alignment in Growth Modeling.

Longitudinal measurement invariance-the consistency of measurement in data collected over time-is a prerequisite for any meaningful inferences of growth patterns. When one or more items measuring the construct of interest show noninvariant measurement properties over time, it leads to biased parameter estimates and inferences on the growth parameters. In this paper, I extend the recently developed alignment-within-confirmatory factor analysis (AwC) technique to adjust for measurement biases for growth models. The proposed AwC method does not require a priori knowledge of noninvariant items and the iterative searching of noninvariant items in typical longitudinal measurement invariance research. Results of a Monte Carlo simulation study comparing AwC with the partial invariance modeling method show that AwC largely reduces biases in growth parameter estimates and gives good control of Type I error rates, especially when the sample size is at least 1,000. It also outperforms the partial invariance method in conditions when all items are noninvariant. However, all methods give biased growth parameter estimates when the proportion of noninvariant parameters is over 25%. Based on the simulation results, I conclude that AO is a viable alternative to the partial invariance method in growth modeling when it is not clear whether longitudinal measurement invariance holds. The current paper also demonstrates AwC in an example modeling neuroticism over three time points using a public data set, which shows how researchers can compute effect size indices for noninvariance in AwC to assess to what degree invariance holds and whether AwC results are trustworthy.

Global measurement of intimate partner violence to monitor Sustainable Development Goal 5.

BACKGROUND: One third of women experience intimate partner violence (IPV) and potential sequelae. Sustainable Development Goal (SDG) 5.2-to eliminate violence against women, including IPV-compels states to monitor such violence. We conducted the first global measurement-invariance assessment of standardised item sets for IPV. METHODS: Demographic and Health Surveys (DHS) from 36 Lower-/Middle-Income Countries (LMICs) administering 18 IPV items during 2012-2018 were included. Analyses were performed separately for two items sets: lifetime physical IPV (seven items) and controlling behaviours (five items). We performed country-specific exploratory and confirmatory factor analyses (EFA/CFA). Datasets meeting benchmarks for acceptable item loadings and model-fit statistics were included in multiple-group CFA (MGCFA) to test for exact measurement invariance. Based on findings, alignment optimization (AO) was performed to assess approximate measurement invariance (< 25% of model parameters non-invariant). For each item set, national rankings based on AO-derived scores and on prevalence estimates were compared. AO-derived scores were correlated with type-specific IPV prevalences to assess correspondence. RESULTS: National rates of physical IPV (5.6-50.5%) and controlling behavior (25.9-84.7%) varied. For each item set, item loadings and model-fit statistics were adequate in country-specific, unidimensional EFAs and CFAs. Both unidimensional constructs lacked exact invariance in MGCFA but achieved approximate invariance in AO analysis (12.3% of model parameters for physical IPV and 6.7% for controlling behaviour non-invariant). For both item sets, national rankings based on AO-derived scores were distributed similarly to rankings based on prevalence. However, estimates often were not significantly different cross-nationally, precluding national-level comparisons regardless of estimation strategy. Three physical-IPV items (slap, twist, choke) and two controlling-behaviour items (meet female friends; contact with family) warrant cognitive testing to improve their psychometric properties. Correlations of AO-derived scores for physical IPV (0.48-0.66) and controlling behaviours (0.49-0.87) with prevalences of lifetime physical, sexual, psychological IPV as well as controlling behaviour varied. CONCLUSIONS: Seven DHS lifetime physical-IPV items and five DHS controlling-behaviour items were approximately invariant across 36 LMICs spanning five world regions, such that cross-national comparisons of factor means are reasonable. Measurement-invariance testing over time will inform their utility to monitor SDG5.2.1; cross-national, cross-time measurement-invariance testing of improved sexual and psychological IPV item-sets is needed.

Adjusting for partial invariance in latent parameter estimation: Comparing forward specification search and approximate invariance methods.

Measurement invariance is the condition that an instrument measures a target construct in the same way across subgroups, settings, and time. In psychological measurement, usually only partial, but not full, invariance is achieved, which potentially biases subsequent parameter estimations and statistical inferences. Although existing literature shows that a correctly specified partial invariance model can remove such biases, it ignores the model uncertainty in the specification search step: flagging the wrong items may lead to additional bias and variability in subsequent inferences. On the other hand, several new approaches, including Bayesian approximate invariance and alignment optimization methods, have been proposed; these methods use an approximate invariance model to adjust for partial measurement invariance without the need to directly identify noninvariant items. However, there has been limited research on these methods in situations with a small number of groups. In this paper, we conducted three systematic simulation studies to compare five methods for adjusting partial invariance. While specification search performed reasonably well when the proportion of noninvariant parameters was no more than one-third, alignment optimization overall performed best across conditions in terms of efficiency of parameter estimates, confidence interval coverage, and type I error rates. In addition, the Bayesian version of alignment optimization performed best for estimating latent means and variances in small-sample and low-reliability conditions. We thus recommend the use of the alignment optimization methods for adjusting partial invariance when comparing latent constructs across a few groups.

The Comparability of Perceived Physical and Mental Health Measures Across Immigrants and Natives in the United States.

The comparative study of perceived physical and mental health in general-and the comparative study of health between the native-born and immigrants, in particular-requires that the groups understand survey questions inquiring about their health in the same way and display similar response patterns. After all, observed differences in perceived health may not reflect true differences but rather cultural bias in the health measures. Research on cross-country measurement equivalence between immigrants and natives on self-reported health measures has received very limited attention to date, resulting in a growing demand for the validation of existing perceived health measures using samples of natives and immigrants and establishing measurement equivalence of health-related assessment tools. This study, therefore, aims to examine measurement equivalence of self-reported physical and mental health indicators between immigrants and natives in the United States. Using pooled data from the 2015-2017 IPUMS Health Surveys, we examine the cross-group measurement equivalence properties of five concepts that are measured by multiple indicators: (1) perceived limitations in activities of daily life; (2) self-reported disability; (3) perceived functional limitations; (4) perceived financial stress; and (5) nonspecific psychological distress. Furthermore, we examine the comparability of these data among respondents of different ethnoracial origins and from different regions of birth, who report few versus many years since migration, their age, gender, and the language used to respond to the interview (e.g., English vs. Spanish). We test for measurement equivalence using multigroup confirmatory factor analysis. The results reveal that health scales are comparable across the examined groups. This finding allows drawing meaningful conclusions about similarities and differences among natives and immigrants on measures of perceived health in these data.

Gas Chromatographic Fingerprint Analysis for the Comparison of Seized Cannabis Samples.

Cannabis sativa L. is widely used as recreational illegal drugs. Illicit Cannabis profiling, comparing seized samples, is challenging due to natural Cannabis heterogeneity. The aim of this study was to use GC-FID and GC-MS herbal fingerprints for intra (within)- and inter (between)-location variability evaluation. This study focused on finding an acceptable threshold to link seized samples. Through Pearson correlation-coefficient calculations between intra-location samples, 'linked' thresholds were derived using 95% and 99% confidence limits. False negative (FN) and false positive (FP) error rate calculations, aiming at obtaining the lowest possible FP value, were performed for different data pre-treatments. Fingerprint-alignment parameters were optimized using Automated Correlation-Optimized Warping (ACOW) or Design of Experiments (DoE), which presented similar results. Hence, ACOW data, as reference, showed 54% and 65% FP values (95 and 99% confidence, respectively). An additional fourth root normalization pre-treatment provided the best results for both the GC-FID and GC-MS datasets. For GC-FID, which showed the best improved FP error rate, 54 and 65% FP for the reference data decreased to 24 and 32%, respectively, after fourth root transformation. Cross-validation showed FP values similar as the entire calibration set, indicating the representativeness of the thresholds. A noteworthy improvement in discrimination between seized Cannabis samples could be concluded.

Cross-cultural equivalence of the Kessler Psychological Distress Scale (K10) across four African countries in a multi-national study of adults.

The Kessler Psychological Distress Scale (K10) has been widely used to screen psychological distress across many countries. However, its performance has not been extensively studied in Africa. The present study sought to evaluate and compare measurement properties of the K10 across four African countries: Ethiopia, Kenya, Uganda, and South Africa. Our hypothesis is that the measure will show equivalence across all. Data are drawn from a neuropsychiatric genetic study among adult participants (N = 9179) from general medical settings in Ethiopia (n = 1928), Kenya (n = 2556), Uganda (n = 2104), and South Africa (n = 2591). A unidimensional model with correlated errors was tested for equivalence across study countries using confirmatory factor analyses and the alignment optimization method. Results displayed 30 % noninvariance (i.e., variation) for both intercepts and factor loadings across all countries. Monte Carlo simulations showed a correlation of 0.998, a good replication of population values, indicating minimal noninvariance, or variation. Items "so nervous," "lack of energy/effortful tasks," and "tired" were consistently equivalent for intercepts and factor loadings, respectively. However, items "depressed" and "so depressed" consistently differed across study countries (R2 = 0) for intercepts and factor loadings for both items. The K10 scale likely functions equivalently across the four countries for most items, except "depressed" and "so depressed." Differences in K10 items were more common in Kenya and Ethiopia, suggesting cultural context may influence the interpretation of some items and the potential need for cultural adaptations in these countries.

Narrow Band Gap Lead Sulfide Hole Transport Layers for Quantum Dot Photovoltaics.

The band structure of colloidal quantum dot (CQD) bilayer heterojunction solar cells is optimized using a combination of ligand modification and QD band gap control. Solar cells with power conversion efficiencies of up to 9.33 ± 0.50% are demonstrated by aligning the absorber and hole transport layers (HTL). Key to achieving high efficiencies is optimizing the relative position of both the valence band and Fermi energy at the CQD bilayer interface. By comparing different band gap CQDs with different ligands, we find that a smaller band gap CQD HTL in combination with a more p-type-inducing CQD ligand is found to enhance hole extraction and hence device performance. We postulate that the efficiency improvements observed are largely due to the synergistic effects of narrower band gap QDs, causing an upshift of valence band position due to 1,2-ethanedithiol (EDT) ligands and a lowering of the Fermi level due to oxidation.

Psychometric Evaluation of the Overexcitability Questionnaire-Two Applying Bayesian Structural Equation Modeling (BSEM) and Multiple-Group BSEM-Based Alignment with Approximate Measurement Invariance.

The Overexcitability Questionnaire-Two (OEQ-II) measures the degree and nature of overexcitability, which assists in determining the developmental potential of an individual according to Dabrowski's Theory of Positive Disintegration. Previous validation studies using frequentist confirmatory factor analysis, which postulates exact parameter constraints, led to model rejection and a long series of model modifications. Bayesian structural equation modeling (BSEM) allows the application of zero-mean, small-variance priors for cross-loadings, residual covariances, and differences in measurement parameters across groups, better reflecting substantive theory and leading to better model fit and less overestimation of factor correlations. Our BSEM analysis with a sample of 516 students in higher education yields positive results regarding the factorial validity of the OEQ-II. Likewise, applying BSEM-based alignment with approximate measurement invariance, the absence of non-invariant factor loadings and intercepts across gender is supportive of the psychometric quality of the OEQ-II. Compared to males, females scored significantly higher on emotional and sensual overexcitability, and significantly lower on psychomotor overexcitability.