Roger L. Brown

The use of a factor-analytic procedure for assessing the validity of an employee safety climate model

This paper assesses the validity of a safety climate measure proposed by Zohar (Safety climate in industrial organizations: Theoretical and applied implications. J. Appl. Psychol. 65(1), 96-101, 1980.) on an American sample of production workers. Using LISREL, confirmatory factor analyses were carried out to test the hypothesis of similar variance-covariance structures (validation of the proposed model). The originally proposed climate model was not supported by the data. An exploratory factor analytic algorithm is then discussed as a means of refining the climate model. A smaller safety climate model was then extracted from the data, and comparisons were made for two groups of employees (accidents versus no accidents). Factorial invariance tests were conducted to test the hypotheses of similar factor patterns, equal units of measurement, equal accuracy of measurement, and equal covariance across factors, between the two groups. The results indicated that the climate structures did not differ between the two groups of interest, subsequently providing a valid and reliable climate measure across the groups. Groups were then compared on climate scores, with differences in climate perception being detected between the groups.

Working Conditions in Primary Care: Physician Reactions and Care Quality

BACKGROUND Adverse primary care work conditions could lead to a reduction in the primary care workforce and lower-quality patient care. OBJECTIVE To assess the relationship among adverse primary care work conditions, adverse physician reactions (stress, burnout, and intent to leave), and patient care. DESIGN Cross-sectional analysis. SETTING 119 ambulatory clinics in New York, New York, and in the upper Midwest. PARTICIPANTS 422 family practitioners and general internists and 1795 of their adult patients with diabetes, hypertension, or heart failure. MEASUREMENTS Physician perception of clinic workflow (time pressure and pace), work control, and organizational culture (assessed survey); physician satisfaction, stress, burnout, and intent to leave practice (assessed by survey); and health care quality and errors (assessed by chart audits). RESULTS More than one half of the physicians (53.1%) reported time pressure during office visits, 48.1% said their work pace was chaotic, 78.4% noted low control over their work, and 26.5% reported burnout. Adverse workflow (time pressure and chaotic environments), low work control, and unfavorable organizational culture were strongly associated with low physician satisfaction, high stress, burnout, and intent to leave. Some work conditions were associated with lower quality and more errors, but findings were inconsistent across work conditions and diagnoses. No association was found between adverse physician reactions, such as stress and burnout, and care quality or errors. LIMITATION The analyses were cross-sectional, the measures were self-reported, and the sample contained an average of 4 patients per physician. CONCLUSION Adverse work conditions are associated with adverse physician reactions, but no consistent associations were found between adverse work conditions and the quality of patient care, and no associations were seen between adverse physician reactions and the quality of patient care.

Assessing specific mediational effects in complex theoretical models

Numerous theoretical structures involve the concept of mediation, the mechanism that accounts for the relation between the predictor and the criterion. The, empirical interpretation of mediation has employed multiple independent models to assess components of the overall structure in a piecemeal manner. This article discusses various limitations of using this independent approach and proposes the use of structural equation modeling (SEM) as an alternative. The article furthermore distinguishes current limitations in using SEM software for assessing mediation in complex structures and presents a strategy for supplemental details that more accurately measure the magnitude of mediational effects, in particular, specific indirect effects.

Efficacy of the indirect approach for estimating structural equation models with missing data: A comparison of five methods

Incomplete or missing data are routinely encountered in structural equation problems. Although current literature supports the use of a direct approach for modeling the missing values in a structural equation model, many situations are not applicable for the effective use of this approach. This leaves the use of an indirect approach for dealing with missing information. There is a general lack of knowledge regarding the efficacy of the use of the indirect approach in structural equation modeling. This article assesses the efficacy of five indirect methods for estimating parameters in a structural equation model with various levels of missing data.

Effect of a Disease-Specific Planning Intervention on Surrogate Understanding of Patient Goals for Future Medical Treatment

OBJECTIVES: To determine whether a disease‐specific planning process can improve surrogate understanding of goals of patients with life‐limiting illnesses for future medical treatments.

Separate and Unequal: Clinics Where Minority and Nonminority Patients Receive Primary Care

BACKGROUND Few studies have examined the influence of physician workplace conditions on health care disparities. We compared 96 primary care clinics in New York, New York, and in the upper Midwest serving various proportions of minority patients to determine differences in workplace organizational characteristics. METHODS Cross-sectional data are from surveys of 96 clinic managers, 388 primary care physicians, and 1701 of their adult patients with hypertension, diabetes mellitus, or congestive heart failure participating in the Minimizing Error, Maximizing Outcome (MEMO) study. Data from 27 clinics with at least 30% minority patients were contrasted with data from 69 clinics with less than 30% minority patients. RESULTS Compared with clinics serving less than 30% minority patients, clinics serving at least 30% minority patients have less access to medical supplies (2.7 vs 3.4, P < .001), referral specialists (3.0 vs 3.5, P < .005) on a scale of 1 (none) to 4 (great), and examination rooms per physician (2.2 vs 2.7, P =.002) . Their patients are more frequently depressed (22.8% vs 12.1%), are more often covered by Medicaid (30.2% vs 11.4%), and report lower health literacy (3.7 vs 4.4) on a scale of 1 (low) to 5 (high) (P < .001 for all). Physicians from clinics serving higher proportions of minority populations perceive their patients as frequently speaking little or no English (27.1% vs 3.4%, P =.004), having more chronic pain (24.1% vs 12.9%, P < .001) and substance abuse problems (15.1% vs 10.1%, P =.005), and being more medically complex (53.1% vs 39.9%) and psychosocially complex (44.9% vs 28.2%) (P < .001 for both). In regression analyses, clinics with at least 30% minority patients are more likely to have chaotic work environments (odds ratio, 4.0; P =.003) and to have fewer physicians reporting high work control (0.2; P =.003) or high job satisfaction (0.4; P =.01). CONCLUSION Clinics serving higher proportions of minority patients have more challenging workplace and organizational characteristics.

Support for the Reliability and Validity of a Six-Item State Anxiety Scale Derived From the State-Trait Anxiety Inventory

Identifying the most efficient and theoretically appropriate methods to assess patient anxiety in fast-paced medical environments may be beneficial for clinical purposes as well as for research. The purpose of this study was to examine the reliability and validity of two previously published six-item versions of the State form of the State-Trait Anxiety Inventory (STAI) and to identify the version that would be most appropriate to use with a sample of parents who had infants with normal or abnormal newborn screens. In the current study, confirmatory factor analyses were conducted to evaluate the fit of the two six-item forms with STAI data collected at three time points from 288 parents of 150 infants. Study groups of parents were based upon infant newborn screens and subsequent diagnostic testing to include cystic fibrosis (CF; n = 26), congenital hypothyroidism (CH; n = 39), CF Carriers (CF–C; n = 45), and healthy infants (H; n = 40). The results showed the version containing items 1, 3, 6, 15, 16, and 17 of the State form of the STAI to be a better fitting model across all three time points, and it had better internal consistency than the version containing items 5, 9, 10, 12, 17, and 20. Both short forms were highly correlated with the 20-item STAI score, and all internal consistency reliabilities were greater than .90. It was concluded that the version containing items 1, 3, 6, 15, 16, and 17 of the State Anxiety scale was a reliable and valid instrument for this study sample.

Lower extremity peripheral arterial disease in hospitalized patients with coronary artery disease.

The prevalence of coronary artery disease (CAD) in patients with peripheral arterial disease (PAD) has been well defined. However, the prevalence of PAD in hospitalized patients with CAD has not been defined. The ankle-brachial index (ABI) is a useful non-invasive tool to screen for PAD. The aim of our study was to assess the prevalence of PAD in hospitalized patients with CAD by measuring the ABI. The study was conducted at the University of Wisconsin Hospital and Clinics inpatient Cardiovascular Medicine Service. Medically stable patients with CAD were invited to participate prior to hospital discharge. Data regarding cardiovascular risk factors, history of previous PAD, physical examination, and ABI were collected. An ABI less than or equal to 0.9 or a history of previous lower extremity vascular invention was considered to be indicative of significant PAD. A total of 100 patients (66 men and 34 women) were recruited. Forty patients were found to have PAD (mean ABI in nonrevascularized patients with PAD = 0.67). By measuring the ABI, 37 (25 men) were positive for PAD and three had an ABI corrected with previous revascularization. Of these patients, 21 (52.5%) had previously documented PAD. Patients with PAD were older (p = 0.003), had a greater smoking history (p = 0.002), were more likely to have diabetes (p = 0.012), hypertension (p = 0.013) and a trend towards more dyslipidemia (p = 0.055). In conclusion, hospitalized patients with CAD are likely to have concomitant PAD. Risk factors for PAD in this patient population include advanced age, history of smoking, diabetes, hypertension, dyslipidemia and abnormal pulse examination. Identification of patients with PAD by measuring the ankle-brachial index is easily done.

Effect of a disease-specific advance care planning intervention on end-of-life care.

To compare patient preferences for end‐of‐life care with care received at the end of life.

Validation of a short form Wisconsin Upper Respiratory Symptom Survey (WURSS-21)

BackgroundThe Wisconsin Upper Respiratory Symptom Survey (WURSS) is an illness-specific health-related quality-of-life questionnaire outcomes instrument.ObjectivesResearch questions were: 1) How well does the WURSS-21 assess the symptoms and functional impairments associated with common cold? 2) How well can this instrument measure change over time (responsiveness)? 3) What is the minimal important difference (MID) that can be detected by the WURSS-21? 4) What are the descriptive statistics for area under the time severity curve (AUC)? 5) What sample sizes would trials require to detect MID or AUC criteria? 6) What does factor analysis tell us about the underlying dimensional structure of the common cold? 7) How reliable are items, domains, and summary scores represented in WURSS? 8) For each of these considerations, how well does the WURSS-21 compare to the WURSS-44, Jackson, and SF-8?Study Design and SettingPeople with Jackson-defined colds were recruited from the community in and around Madison, Wisconsin. Participants were enrolled within 48 hours of first cold symptom and monitored for up to 14 days of illness. Half the sample filled out the WURSS-21 in the morning and the WURSS-44 in the evening, with the other half reversing the daily order. External comparators were the SF-8, a 24-hour recall general health measure yielding separate physical and mental health scores, and the eight-item Jackson cold index, which assesses symptoms, but not functional impairment or quality of life.ResultsIn all, 230 participants were monitored for 2,457 person-days. Participants were aged 14 to 83 years (mean 34.1, SD 13.6), majority female (66.5%), mostly white (86.0%), and represented substantive education and income diversity. WURSS-21 items demonstrated similar performance when embedded within the WURSS-44 or in the stand-alone WURSS-21. Minimal important difference (MID) and Guyatts responsiveness index were 10.3, 0.71 for the WURSS-21 and 18.5, 0.75 for the WURSS-44. Factorial analysis suggested an eight dimension structure for the WURSS-44 and a three dimension structure for the WURSS-21, with composite reliability coefficients ranging from 0.87 to 0.97, and Cronbachs alpha ranging from 0.76 to 0.96. Both WURSS versions correlated significantly with the Jackson scale (W-21 R = 0.85; W-44 R = 0.88), with the SF-8 physical health (W-21 R = -0.79; W-44 R = -0.80) and SF-8 mental health (W-21 R = -0.55; W-44 R = -0.60).ConclusionThe WURSS-44 and WURSS-21 perform well as illness-specific quality-of-life evaluative outcome instruments. Construct validity is supported by the data presented here. While the WURSS-44 covers more symptoms, the WURSS-21 exhibits similar performance in terms of reliability, responsiveness, importance-to-patients, and convergence with other measures.