How Good are Our Measures? Investigating the Appropriate Use of Factor Analysis for Survey Instruments

Background: Evaluation work frequently utilizes factor analysis to establish the dimensionality, reliability, and stability of surveys. However, survey data is typically ordinal, violating the assumptions of most statistical methods, and thus is often factor-analyzed inappropriately. Purpose: This study illustrates the salient analytical decisions for factor-analyzing ordinal survey data appropriately and demonstrates the repercussions of inappropriate analyses. Setting: The data used for this study are drawn from an evaluation of the efficacy of a drama-based approach to teaching Shakespeare in elementary and middle school.  Intervention: Not applicable. Research Design: Survey research. Data Collection and Analysis: Four factor analytic methods were compared: a traditional exploratory factor analysis (EFA), a full-information EFA, and two EFAs within the confirmatory factor analysis framework (E/CFA) conducted according to the Jöreskog method and the Gugiu method. Findings: Methods appropriate for ordinal data produce better models, the E/CFAs outperform the EFAs, and the Gugiu method demonstrates greater model interpretability and stability than the Jöreskog method. These results suggest that the Gugiu E/CFA may be the preferable factor analytic method for use with ordinal data. Practical applications of these findings are discussed. Keywords: factor analysis; ordinal data; E/CFA; survey research

Quantitative Methods for Estimating the Reliability of Qualitative Data

Background: Measurement is a indispensable aspect of conducting both quantitative and qualitative research and evaluation. With respect to qualitative research, measurement typically occurs during the coding process.   Purpose: This paper presents quantitative methods for determining the reliability of conclusions from qualitative data sources. Although some qualitative researchers disagree agree with such application, a link between the qualitative and quantitative fields is successfully established through data collection and coding procedures.   Setting: Not applicable.   Intervention: Not applicable. Research Design: Case study.   Data Collection and Analysis: Narrative data were collected from a random sample of 528 undergraduate students and 28 professors.   Findings: The calculation of the kappa statistic, weighted kappa statistic, ANOVA Binary Intraclass Correlation, and Kuder-Richardson 20 is illustrated through a fictitious example. Formulae are presented so that the researcher can calculate these estimators without the use of sophisticated statistical software.   Keywords: qualitative coding; qualitative methodology; reliability coefficient

High-quality chronic care delivery improves experiences of chronically ill patients receiving care

__Abstract__ Objective. Investigate whether high-quality chronic care delivery improved the experiences of patients. Design. This study had a longitudinal design. Setting and Participants. We surveyed professionals and patients in 17 disease management programs targeting patients with cardiovascular diseases, chronic obstructive pulmonary disease, heart failure, stroke, comorbidity and eatin

Experimental investigation of the effect of ionization on the 51V(p,n)51Cr reaction

The investigation of the effects of average atomic ionization on nuclear reactions is of prime importance for nuclear astrophysics. No direct experimental measurement using a plasma target has been done yet. In this regard, we measured for the first time the neutron production of a (p,n) reaction in different states of ionization. The studied nuclear reaction was 51V(p,n)51Cr. We measured a significantly lower neutron production than expected when the target was ionized, even when taking into account existing electron screening theory or the effect of the stopping power in the target on the injected proton beam. This experiment is a first step in the process to characterize the influence of ionization at astrophysically relevant energies.Comment: 20 pages, 10 figures, submitted to EP

First πK\pi K atom lifetime and πK\pi K scattering length measurements

The results of a search for hydrogen-like atoms consisting of $\pi^{\mp}K^{\pm}$ mesons are presented. Evidence for $\pi K$ atom production by 24 GeV/c protons from CERN PS interacting with a nickel target has been seen in terms of characteristic $\pi K$ pairs from their breakup in the same target ($178 \pm 49$) and from Coulomb final state interaction ($653 \pm 42$). Using these results the analysis yields a first value for the $\pi K$ atom lifetime of $\tau=(2.5_{-1.8}^{+3.0})$ fs and a first model-independent measurement of the S-wave isospin-odd $\pi K$ scattering length $\left|a_0^-\right|=\frac{1}{3}\left|a_{1/2}-a_{3/2}\right|= \left(0.11_{-0.04}^{+0.09} \right)M_{\pi}^{-1}$ ($a_I$ for isospin $I$).Comment: 14 pages, 8 figure

Determination of ππ\pi\pi scattering lengths from measurement of π+π−\pi^+\pi^- atom lifetime

The DIRAC experiment at CERN has achieved a sizeable production of $\pi^+\pi^-$ atoms and has significantly improved the precision on its lifetime determination. From a sample of 21227 atomic pairs, a 4% measurement of the S-wave $\pi\pi$ scattering length difference $|a_0-a_2| = (.0.2533^{+0.0080}_{-0.0078}|_\mathrm{stat}.{}^{+0.0078}_{-0.0073}|_\mathrm{syst})M_{\pi^+}^{-1}$ has been attained, providing an important test of Chiral Perturbation Theory.Comment: 6 pages, 6 figure

The chronic care model: Congruency and predictors among patients with cardiovascular diseases and chronic obstructive pulmonary disease in the Netherlands

Objective: The Chronic Care Model (CCM) achieved widespread acceptance and reflects the core elements of patient-centred care in chronic diseases such as CVD and COPD. Our aim is to assess the extent to which current care for CVD and COPD patients aligns with the CCM in Dutch healthcare practices in the early stages of implementing disease-management programs, thereby revealing possible predictors that tell us whether certain patients are more likel

Investigation of K+K−K^+K^- pairs in the effective mass region near 2mK2m_K

The DIRAC experiment at CERN investigated in the reaction $\rm{p}(24~\rm{GeV}/c) + Ni$ the particle pairs $K^+K^-, \pi^+ \pi^-$ and $p \bar{p}$ with relative momentum $Q$ in the pair system less than 100 MeV/c. Because of background influence studies, DIRAC explored three subsamples of $K^+K^-$ pairs, obtained by subtracting -- using time-of-flight (TOF) technique -- background from initial $Q$ distributions with $K^+K^-$ sample fractions more than 70\%, 50\% and 30\%. The corresponding pair distributions in $Q$ and in its longitudinal projection $Q_L$ were analyzed first in a Coulomb model, which takes into account only Coulomb final state interaction (FSI) and assuming point-like pair production. This Coulomb model analysis leads to a $K^+K^-$ yield increase of about four at $Q_L=0.5$ MeV/c compared to 100 MeV/c. In order to study contributions from strong interaction, a second more sophisticated model was applied, considering besides Coulomb FSI also strong FSI via the resonances $f_0(980)$ and $a_0(980)$ and a variable distance $r^*$ between the produced $K$ mesons. This analysis was based on three different parameter sets for the pair production. For the 70\% subsample and with best parameters, $3680\pm 370$ $K^+K^-$ pairs was found to be compared to $3900\pm 410$ $K^+K^-$ extracted by means of the Coulomb model. Knowing the efficiency of the TOF cut for background suppression, the total number of detected $K^+K^-$ pairs was evaluated to be around $40000\pm 10\%$, which agrees with the result from the 30\% subsample. The $K^+K^-$ pair number in the 50\% subsample differs from the two other values by about three standard deviations, confirming -- as discussed in the paper -- that experimental data in this subsample is less reliable