Patient-Physician Concordance for Quantitative Formats and Treatment Options and the Relationship with State Anxiety.

Patient-physician concordance about topics discussed in a clinic visit is essential for effective communication but may be difficult to achieve in cancer care. We conducted a multicenter, observational study at two Midwestern oncology clinics. A sample of 48 English-speaking or Spanish-speaking women with newly diagnosed stage 0-3 breast cancer completed surveys before and after a visit with an oncologist. Patient-physician dyads were coded as concordant if both patient and physician follow-up self-reports agreed whether (or not) specific treatments were discussed (i.e., treatment option concordance; mastectomy, lumpectomy, hormone therapy, neoadjuvant, and adjuvant chemotherapy) and whether risk was described using certain quantitative formats (i.e., quantitative format concordance; percentages, proportions out of 100 and 1000, graphs, pictures, evidence from clinical studies, cancer stage). Agreement was determined using percent agreement and prevalence-adjusted bias-adjusted kappa (PABAK). Pearson's correlations were used to determine relationships between anxiety and each measure concordance. Percent concordance was higher for treatment concordance (73.3%) compared to quantitative format concordance (64.5%), and PABAK scores tended to be higher for treatment options (PABAK = .21-.78). Both treatment and quantitative format concordance were negatively associated with pre-visit state anxiety, but only treatment concordance was statistically significant (treatment: r = - .504, p = .001; quantitative format: r = - .096, p = .523). Our study indicates moderate patient-physician concordance in early breast cancer care communication and that patient anxiety may impact the ability for patients and physicians to agree on the content communicated in a clinic visit.

Using Differential Item Functioning to Test for Interrater Reliability in Constructed Response Items.

The purpose of this study was to investigate a new way of evaluating interrater reliability that can allow one to determine if two raters differ with respect to their rating on a polytomous rating scale or constructed response item. Specifically, differential item functioning (DIF) analyses were used to assess interrater reliability and compared with traditional interrater reliability measures. Three different procedures that can be used as measures of interrater reliability were compared: (1) intraclass correlation coefficient (ICC), (2) Cohen's kappa statistic, and (3) DIF statistic obtained from Poly-SIBTEST. The results of this investigation indicated that DIF procedures appear to be a promising alternative to assess the interrater reliability of constructed response items, or other polytomous types of items, such as rating scales. Furthermore, using DIF to assess interrater reliability does not require a fully crossed design and allows one to determine if a rater is either more severe, or more lenient, in their scoring of each individual polytomous item on a test or rating scale.

Communication and Shared Decision Making in the Breast Cancer Treatment Consultation: A Comparative Analysis of English- and Spanish-Speaking Patients.

Background. Communication in the breast cancer treatment consultation is complex. Language barriers may increase the challenge of achieving patient-centered communication and effective shared decision making. Design. We conducted a prospective cohort study among Spanish- and English-speaking women with stage 0 to 3 breast cancer in two urban medical centers in the Midwestern United States. Patient centeredness of care and decisional conflict were compared between Spanish- and English-speaking participants using the Interpersonal Processes of Care (IPC) and Decision Conflict Scale (DCS), respectively. Clinician behaviors of shared decision making were assessed from consultation audio-recordings using the 12-item Observing Patient Involvement in Decision Making (OPTION) scale. Multivariate regression analyses were conducted to control for differences in baseline characteristics and clinician specialty. Results. Fifteen Spanish-speaking and 35 English-speaking patients were enrolled in the study. IPC scores (median, interquartile range [IQR]) were higher (less patient centered) in Spanish- versus English-speaking participants in the domains of lack of clarity (2.5, 1-3 v. 1.5, 1-2), P = 0.028; perceived discrimination (1.1, 1-1 v. 1.0, 1-1), P = 0.047; and disrespectful office staff (1.25, 1-2 v. 1.0, 1-1), P < 0.0005 (Wilcoxon rank-sum test). OPTION scores (median, IQR) were lower in Spanish- versus English-speaking participants (21.9, 17.7-27.1 v. 31.3, 26.6-39.6), P = 0.001 (Wilcoxon rank-sum test). In multivariate analysis, statistically significant differences persisted in the IPC lack of clarity and disrespectful office staff between Spanish- and English-speaking groups. Conclusions. Our findings highlight challenges in cancer communication for Spanish-speaking patients, particularly with respect to perceived patient centeredness of communication. Further cross-cultural studies are needed to ensure effective communication and shared decision making in the cancer consultation.

Examining Parameter Estimation when Treating Semi-Mixed Multidimensional Constructs as Unidimensional.

In this study, parameter estimation error was examined when three dimensional tests of a semi-mixed structure were estimated unidimensionally. Since previous studies have generally focused on two-dimensional mixed structured tests or three-dimensional approximately simple structured tests, this study adds to the literature by considering the impact of fitting a unidimensional model to multidimensional data using a test structure that has not previously been considered. Test structure, interdimensional correlation, difficulty of the test, and different underlying distributions of ability were considered. Test length was set at 30 items for all conditions. Although test length was fixed, the number of approximately simple and complex items varied. Under all conditions for both moderately difficult and difficult tests, the lowest error values for all discrimination parameters, with the exception of MDISC, were obtained, surprisingly, with a correlation of 0.00. The lowest RMSE values for the difficulty parameter were obtained for tests of medium difficulty when the underlying ability distribution was simulated as standard normal for all three dimensions. The estimation errors associated with the difficulty parameter were greatly impacted by differences in the underlying ability distributions. Ability estimation errors associated with the unidimensional estimate of ability decreased as the correlation between dimensions increased.

Improving Communication in Breast Cancer Treatment Consultation: Use of a Computer Test of Health Numeracy.

Background: Communication of statistics and probability is challenging in the cancer care setting. The objectives of this study are to evaluate a novel approach to cancer communication through the use of a computer assessment of patient health numeracy. Methods: We conducted a pilot study of the Computer Adapted Test of Numeracy Understanding in Medicine Instrument (CAT-NUMi) before the cancer treatment consultation for women with stage 0-3 breast cancer. Patient outcomes included the interpersonal processes of care (IPC) and the decisional conflict scale. We evaluated clinician use of numeric information in the cancer consultation and assessed feasibility outcomes from the clinician and patient perspective. Results: Patient participants (n = 50) had a median (interquartile range) age of 51 years (46-61), 70% were English speaking, and 30% Spanish speaking. Decisional conflict was low with a mean (standard deviation [SD]) decisional conflict score of 17.4 (12.3). The lack of clarity score (range 1-5) on the IPC was low (mean, SD),1.70 (0.71), indicating clear communication. Clinicians more often used percentages in communicating prognosis among those with higher numeracy scores (median, range): high (2, 0-8), medium (1, 0-7), and low (0, 0-8); p = 0.04. The patient experience of taking the CAT-NUMi was rated as very good or excellent by 65%, fair by 33%, and poor by 2% of patients. Conclusion: Screening for health numeracy with a short computer-based test may be a feasible strategy to optimize clear communication in the cancer treatment consultation. Further studies are needed to evaluate this strategy across cancer treatment clinical settings and populations.

Tailoring Educational and Behavioral Interventions to Level of Health Literacy: A Systematic Review.

Background: The relative value of universal compared to contingent approaches to communication and behavioral interventions for persons of low health literacy remains unknown. Objective: To examine the effectiveness of interventions that are tailored to individual health literacy level compared to nontailored interventions on health-related outcomes. Design: Systematic review. Data Sources: PubMed and Embase databases. Eligibility Criteria: Studies were eligible if they were in English, used an experimental or observational design, included an intervention that was tailored based on the individual's level of education, health literacy or health numeracy, and had a comparator group in which the intervention was not tailored to individual characteristics. Review Methods: Databases were searched from inception to January 2016, and the retrieved reference lists hand searched. Abstracts that met PICOS criteria underwent dual review for data extraction to assess study details and study quality. A qualitative synthesis was conducted. Results: Of 2,323 unique citations, 458 underwent full review, and 9 met criteria for the systematic review. Five studies were positive and rated as good quality, 3 were negative with 2 of those of good quality, and 1 had mixed results (fair quality). Positive studies were conducted in the clinical domains of hypertension, diabetes, and depression with interventions including educational materials, disease management sessions, literacy training, and physician notification of limited health literacy among patients. Negative studies were conducted in the clinical domains of heart disease, glaucoma, and nutrition with interventions including medication reconciliation and educational materials. Conclusions: Tailoring communication and behavioral interventions to the individual level of health literacy may be an effective strategy to improve knowledge and indicators of disease control in selected clinical settings.

Using a Multidimensional IRT Framework to Better Understand Differential Item Functioning (DIF): A Tale of Three DIF Detection Procedures.

The theoretical reason for the presence of differential item functioning (DIF) is that data are multidimensional and two groups of examinees differ in their underlying ability distribution for the secondary dimension(s). Therefore, the purpose of this study was to determine how much the secondary ability distributions must differ before DIF is detected. Two-dimensional binary data sets were simulated using a compensatory multidimensional item response theory (MIRT) model, incrementally varying the mean difference on the second dimension between reference and focal group examinees while systematically increasing the correlation between dimensions. Three different DIF detection procedures were used to test for DIF: (1) SIBTEST, (2) Mantel-Haenszel, and (3) logistic regression. Results indicated that even with a very small mean difference on the secondary dimension, smaller than typically considered in previous research, DIF will be detected. Additional analyses indicated that even with the smallest mean difference considered in this study, 0.25, statistically significant differences will almost always be found between reference and focal group examinees on subtest scores consisting of items measuring the secondary dimension.

Utility of the injured trauma survivor screen to predict PTSD and depression during hospital admission.

BACKGROUND: The brief, easily administered screen, the Injured Trauma Survivor Screen (ITSS), was created to identify trauma survivors at risk for development of posttraumatic stress disorder (PTSD) and depression. METHODS: An item pool of PTSD risk factors was created and given, along with a previously created screen, to patients admitted to two Level 1 trauma centers. The Clinician Administered PTSD Scale for DSM-5, the PTSD Checklist for DSM-5, and the Center for Epidemiological Studies Depression Scale Revised were given during a 1-month follow-up. A total of 139 participants were included (n = 139; µ age = 41.06; 30.9% female; 47.5% White/Caucasian; 39.6% Black/African American; 10.1% Latino/Hispanic; 1.4% American Indian; and 1.4% other). Stepwise bivariate logistic regression was used to determine items most strongly associated with PTSD and depression diagnosis 1 month after injury. RESULTS: Forty participants met criteria for a PTSD diagnosis and 28 for depression at follow-up (22 comorbid). ROC curve analysis was used to determine sensitivity (PTSD = 75.00, Depression = 75.00), specificity (PTSD = 93.94, Depression = 95.5), NPV (PTSD = 90.3, Depression = 80.8), and PPV (PTSD = 83.3, Depression = 93.8) of the final nine-item measure. CONCLUSIONS: This study provides evidence for the utility of a predictive screen, the ITSS, to predict which injured trauma survivors admitted to the hospital are at the most risk for developing symptoms of PTSD and depression 1 month after injury. The ITSS is a short, easily administered tool that can aid in reducing the untreated cases of PTSD and depression. LEVEL OF EVIDENCE: Prognostic study, level III.

Development and Validation of the Spanish Numeracy Understanding in Medicine Instrument.

BACKGROUND: The Spanish-speaking population in the U.S. is large and growing and is known to have lower health literacy than the English-speaking population. Less is known about the health numeracy of this population due to a lack of health numeracy measures in Spanish. OBJECTIVE: we aimed to develop and validate a short and easy to use measure of health numeracy for Spanish-speaking adults: the Spanish Numeracy Understanding in Medicine Instrument (Spanish-NUMi). DESIGN: Items were generated based on qualitative studies in English- and Spanish-speaking adults and translated into Spanish using a group translation and consensus process. Candidate items for the Spanish NUMi were selected from an eight-item validated English Short NUMi. Differential Item Functioning (DIF) was conducted to evaluate equivalence between English and Spanish items. Cronbach's alpha was computed as a measure of reliability and a Pearson's correlation was used to evaluate the association between test scores and the Spanish Test of Functional Health Literacy (S-TOFHLA) and education level. PARTICIPANTS: Two-hundred and thirty-two Spanish-speaking Chicago residents were included in the study. KEY RESULTS: The study population was diverse in age, gender, and level of education and 70 % reported Mexico as their country of origin. Two items of the English eight-item Short NUMi demonstrated DIF and were dropped. The resulting six-item test had a Cronbach's alpha of 0.72, a range of difficulty using classical test statistics (percent correct: 0.48 to 0.86), and adequate discrimination (item-total score correlation: 0.34-0.49). Scores were positively correlated with print literacy as measured by the S- TOFHLA (r = 0.67; p < 0.001) and varied as predicted across grade level; mean scores for up to eighth grade, ninth through twelfth grade, and some college experience or more, respectively, were 2.48 (SD ± 1.64), 4.15 (SD ± 1.45), and 4.82 (SD ± 0.37). CONCLUSIONS: The Spanish NUMi is a reliable and valid measure of important numerical concepts used in communicating health information.

Development and validation of the numeracy understanding in Medicine Instrument short form.

Health numeracy can be defined as the ability to understand and use numeric information and quantitative concepts in the context of health. The authors previously reported the development of the Numeracy Understanding in Medicine Instrument (NUMi), a 20-item test developed using item response theory. The authors now report the development and validation of a short form of the NUMi. Item statistics were used to identify a subset of 8 items representing a range of difficulty and content areas. Internal reliability was evaluated with Cronbach's alpha. Divergent and convergent validity was assessed by comparing scores of the S-NUMI with existing measures of education, print and numeric health literacy, mathematic achievement, cognitive reasoning, and the original NUMi. The 8-item scale had adequate reliability (α=.72) and was strongly correlated to the 20-item NUMi (α=.92). S-NUMi scores were strongly correlated with the Lipkus Expanded Health Numeracy Scale (α=.62), the Wide Range of Achievement Test-Mathematics (α=.72), and the Wonderlic Cognitive Ability Test (α=.76). Moderate correlation was found with education level (α=.58) and print literacy as measured by the Test of Functional Health Literacy in Adults (α=.49). Results show that the short form of the NUMi is a reliable and valid measure of health numeracy feasible for use in clinical and research settings.

The numeracy understanding in medicine instrument: a measure of health numeracy developed using item response theory.

BACKGROUND: Health numeracy can be defined as the ability to understand and apply information conveyed with numbers, tables and graphs, probabilities, and statistics to effectively communicate with health care providers, take care of one's health, and participate in medical decisions. OBJECTIVE: To develop the Numeracy Understanding in Medicine Instrument (NUMi) using item response theory scaling methods. DESIGN: A 20-item test was formed drawing from an item bank of numeracy questions. Items were calibrated using responses from 1000 participants and a 2-parameter item response theory model. Construct validity was assessed by comparing scores on the NUMi to established measures of print and numeric health literacy, mathematic achievement, and cognitive aptitude. PARTICIPANTS: Community and clinical populations in the Milwaukee and Chicago metropolitan areas. RESULTS: Twenty-nine percent of the 1000 respondents were Hispanic, 24% were non-Hispanic white, and 42% were non-Hispanic black. Forty-one percent had no more than a high school education. The mean score on the NUMi was 13.2 (s = 4.6) with a Cronbach α of 0.86. Difficulty and discrimination item response theory parameters of the 20 items ranged from -1.70 to 1.45 and 0.39 to 1.98, respectively. Performance on the NUMi was strongly correlated with the Wide Range Achievement Test-Arithmetic (0.73, P < 0.001), the Lipkus Expanded Numeracy Scale (0.69, P < 0.001), the Medical Data Interpretation Test (0.75, P < 0.001), and the Wonderlic Cognitive Ability Test (0.82, P < 0.001). Performance was moderately correlated to the Short Test of Functional Health Literacy (0.43, P < 0.001). LIMITATIONS: The NUMi was found to be most discriminating among respondents with a lower-than-average level of health numeracy. CONCLUSIONS: The NUMi can be applied in research and clinical settings as a robust measure of the health numeracy construct.

The meaning of numbers in health: exploring health numeracy in a Mexican-American population.

BACKGROUND: Health numeracy can be defined as the ability to use numeric information in the context of health. The interpretation and application of numbers in health may vary across cultural groups. OBJECTIVE: To explore the construct of health numeracy among persons who identify as Mexican American. DESIGN: Qualitative focus group study. Groups were stratified by preferred language and level of education. Audio-recordings were transcribed and Spanish groups (n = 3) translated to English. An analysis was conducted using principles of grounded theory. PARTICIPANTS: A purposeful sample of participants from clinical and community sites in the Milwaukee and Chicago metropolitan areas. MAIN MEASURES: A theoretical framework of health numeracy was developed based upon categories and major themes that emerged from the analysis. KEY RESULTS: Six focus groups were conducted with 50 participants. Initial agreement in coding was 59-67% with 100% reached after reconciliation by the coding team. Three major themes emerged: 1) numeracy skills are applied to a broad range of communication and decision making tasks in health, 2) affective and cognitive responses to numeric information influence use of numbers in the health setting, and 3) there exists a strong desire to understand the meaning behind numbers used in health. The findings informed a theoretical framework of health numeracy. CONCLUSIONS: Numbers are important across a range of skills and applications in health in a sample of an urban Mexican-American population. This study expands previous work that strives to understand the application of numeric skills to medical decision making and health behaviors.

Evaluating existing measures of health numeracy using item response theory.

OBJECTIVE: To evaluate existing measures of health numeracy using item response theory (IRT). METHODS: A cross-sectional study was conducted. Participants completed assessments of health numeracy measures including the Lipkus expanded health numeracy scale (Lipkus), and the Medical Data Interpretation Test (MDIT). The Lipkus and MDIT were scaled with IRT utilizing the two-parameter logistic model. RESULTS: Three-hundred and fifty-nine (359) participants were surveyed. Classical test theory parameters and IRT scaling parameters of the numeracy measures found most items to be at least moderately discriminating. Modified versions of the Lipkus and MDIT were scaled after eliminating items with low discrimination, high difficulty parameters, and poor model fit. The modified versions demonstrated a good range of discrimination and difficulty as indicated by the test information functions. CONCLUSION: An IRT analysis of the Lipkus and MDIT indicate that both health numeracy scales discriminate well across a range of ability. PRACTICE IMPLICATIONS: Health numeracy skills are needed in order for patients to successfully participate in their medical care. The accurate assessment of health numeracy may help health care providers to tailor patient education interventions to the patient's level of understanding and ability. Item response theory scaling methods can be used to evaluate the discrimination and difficulty of individual items as well as the overall assessment.

Crassulacean acid metabolism in Isoetes bolanderi in high elevation oligotrophic lakes.

Isoetes bolanderi dominates the littoral flora of Siesta (elevation 2,440 m) and Ellery (2,905 m) lakes in the Sierra Nevada Range of California, USA. Both lakes are sparesly vegetated and I. bolanderi maintained aboveground oven dry weight of 30-50 m-22 through most of the 1981 summer growing season. Plants at the higher elevation Ellery Lake were half as large as plants at Siesta Lake and had substantially more biomass in corms. Titratable acidity levels in Isoetes leaves showed a diurnal fluctuation <50 µeq g1 fresh weight early in the season at the highest elevation site but this increased to ∼300 µeq g1 FW by mid-summer; starch and chlorophyll levels likewise increased in the leaves over this time. Throughout the season the magnitude of the diurnal acid change was comparable inIsoetes from both lakes but the dynamics of daytime deacidification were not. Averaged over the season, total daytime deacidification at Ellery Lake was 65% complete by noon whereas at Siesta Lake it was only 22% complete by noon. It is suggested that this may be related to the fact that Siesta Lake was more acidic and thus more carbon was in the form of free CO2. In both lakes water chemistry showed no consistent diurnal fluctuation in pH or free CO2 though total inorganic carbon levels were at the extreme low end for aquatic habitats. The studies reported here suggest that under extremely low inorganic carbon levels there may be selection for nighttime CO2 assimilation. Consistent with this hypothesis is the observation that emergent I. bolanderi plants, resulting from fluctuating water levels, initiated leaves with stomata(unlike adjacent submerged plants) and, although these leaves had substantially higher chlorophyll levels, they showed an order of magnitude less acid fluctuation than submerged leaves.