Dev S. Pathak

Costs and outcomes of acute kidney injury (AKI) following cardiac surgery

BACKGROUND Acute kidney injury (AKI) is a recognized complication of cardiac surgery; however, the variability in costs and outcomes reported are due, in part, to different criteria for diagnosing and classifying AKI. We determined costs, resource use and mortality rate of patients. We used the serum creatinine component of the RIFLE system to classify AKI. METHODS A retrospective cohort study was conducted from the electronic data repository at the University of Pittsburgh Medical Center of patients who underwent cardiac surgery and had an elevation (>or=0.5 mg/dl) of serum creatinine postoperatively. Data were compared to age- and APACHE III-matched controls. Cost, mortality and resource use of AKI patients were determined postoperatively for each of the three RIFLE classes on the basis of changes in serum creatinine. RESULTS Of the 3741 admissions, 258 (6.9%) had AKI and were classified as RIFLE-R 138 (3.7%), RIFLE-I 70 (1.9%) and RIFLE-F 50 (1.3%). Total and departmental level costs, length of stay (LOS) and requirement for renal replacement therapy (RRT) were higher in AKI patients compared to controls. Statistically significant differences in all costs, mortality rate and requirement for RRT were seen in the patients stratified into RIFLE-R, RIFLE-I and RIFLE-F. Even patients with the smallest change in serum creatinine, namely RIFLE-R, had a 2.2-fold greater mortality, a 1.6-fold increase in ICU LOS and 1.6-fold increase in total postoperative costs compared to controls. DISCUSSION Costs, LOS and mortality are higher in postoperative cardiac surgery patients who develop AKI using RIFLE criteria, and these values increase as AKI severity worsens.

Validity and reliability of the Migraine-Specific Quality of Life Questionnaire (MSQ version 2.1)

Objective.–To assess the scaling properties, reliability, and validity of the revised Migraine‐Specific Quality of Life Questionnaire (MSQ) (Version 2.1)

The Measurement of Social Support: The Social Support Network Inventory

HE PLURALISTIC OR BIOPYSCHOSOCIAL model of illness acknowledges that social factors play a role in the development of physical and emotional illness. Or, in Cassel’s language, that there is a “contribution of the social environment to host resistance.“’ Research continues to explore those social variables which directly or indirectly contribute to pathophysiologic processes, vulnerability to illness, symptom formation, and treatment response. One major area of research concerns the influence of stress and life events beginning with early writings of Cannon2 and Adolf Meyer.-’ Since the development of quantitative instruments for measuring life events, pioneered by Holmes and Rahe,4 there has been a flurry of studies examining the relationship between this variable and a variety of dependent symptom variables. Unfortunately, life events have rarely accounted for more than 15% and frequently less than 10% of the variance in any psychiatric outcome measures. Cognizant of the limits of a parsimonious theory linking stressful life events to illness, Caplan5 and others have suggested that social supports or social networks may be an intermediary variable serving to buffer the potentially negative effects of stress. Subsequently, a variety of investigators have shown an inverse association between specific aspects of social support and the development of depression in the general population6 and in recent widows;’ an inverse relationship between social support and symptom severity has also been shown in unipolar populations. R.9 Components of social support have also been examined in relationship to schizophrenia,‘O anxiety,” and psychosomatic disorders.r2 In most of these studies, social support has emerged as a better predictor of outcome than life events, causing speculation that there is a direct effect in addition to that of buffering stress. Although the use of specific questions on aspects of social support (eg, number of friends, relatives in the immediate geographic area, presence of a close contidante) are useful, it became clear by the mid-70’s that quantitative instruments were needed to reliably assess social support in research investigations and clinicians. This report presents the rationale, design, and psychometric testing of one instrument-the Social Support Network Inventory (SSNI)--which the authors began developing in 1979. It should be noted that other investigators such as Pattison” began developing similar instruments at that time; an excellent review of the methodology of these instruments has been provided by Lin.13

Modelling the EuroQol data: a comparison of discrete choice conjoint and conditional preference modelling

This article compares two measurement strategies for measuring EuroQol health state preferences: (a) conditional preference modelling, implemented using rating scale and standard gamble scaling methods and (b) discrete choice conjoint modelling. The nature of the model form of the EuroQol health status preference function and the predictive ability of each measurement strategy formed the basis of the comparison. Data were collected via personal interviews with 140 US patients, 139 of whom provided usable responses. Both strategies supported a multiplicative model form as representative of the EuroQol health status preference function and were acceptable in terms of predictive ability. The agreement of the two measurement strategies on the nature of the model form provides evidence of the convergent validity of the multiplicative nature of the EuroQol health status preference function in this patient population. Since both strategies were found to be acceptable in terms of predictive ability, further research comparing preference scores and measuring respondent evaluations of the methodologies is necessary to illustrate the relative strengths and weaknesses of different health state preference measurement methodologies.

Measurement of Outcomes in Adults Receiving Pharmaceutical Care in a Comprehensive Asthma Outpatient Clinic

We hypothesized that a pharmacist‐provided comprehensive education program in conjunction with care provided by a pulmonologist would lead to improved economic, clinical, and humanistic outcomes in adults with asthma, compared with similar patients receiving care from a pulmonologist alone. The experimental group reported receiving more information about asthma self‐management (p=0.001), were more likely to monitor peak flow readings (p=0.004), and had increased satisfaction with care, and perceived higher quality of care. Both groups had less lost productivity, fewer emergency department visits, fewer hospitalizations, and fewer physician visits, as well as improvement in symptoms scores within 45 days. Both groups improved in all functional status domains except the mental component score of the SF‐12. Our results show a positive impact on outcomes in adults with asthma who received pharmaceutical care.

Are the Naranjo criteria reliable and valid for determination of adverse drug reactions in the intensive care unit

BACKGROUND The Naranjo criteria are frequently used for determination of causality for suspected adverse drug reactions (ADRs); however, the psychometric properties have not been studied in the critically ill. OBJECTIVE To evaluate the reliability and validity of the Naranjo criteria for ADR determination in the intensive care unit (ICU). METHODS All patients admitted to a surgical ICU during a 3-month period were enrolled. Four raters independently reviewed 142 suspected ADRs using the Naranjo criteria (review 1). Raters evaluated the 142 suspected ADRs 3–4 weeks later, again using the Naranjo criteria (review 2). Inter-rater reliability was tested using the kappa statistic. The weighted kappa statistic was calculated between reviews 1 and 2 for the intra-rater reliability of each rater. Cronbach alpha was computed to assess the inter-item consistency correlation. The Naranjo criteria were compared with expert opinion for criterion validity for each rater and reported as a Spearman rank (rs) coefficient. RESULTS The kappa statistic ranged from 0.14 to 0.33, reflecting poor inter-rater agreement. The weighted kappa within raters was 0.5402–0.9371. The Cronbach alpha ranged from 0.443 to 0.660, which is considered moderate to good. The rs coefficient range was 0.385–0.545; all rs coefficients were statistically significant (p < 0.05). CONCLUSIONS Inter-rater reliability is marginal; however, within-rater evaluation appears to be consistent. The inter-item correlation is expected to be higher since all questions pertain to ADRs. Overall, the Naranjo criteria need modification for use in the ICU to improve reliability, validity, and clinical usefulness.

Productivity-Cost Controversies in Cost-Effectiveness Analysis: Review and Research Agenda

Productivity costs represent true costs to society and should not be ignored in a cost-effectiveness analysis. However, there is dissension among health economists regarding measurement of productivity costs. Certain health economists argue for inclusion of productivity costs in the denominator of the cost-effectiveness ratio, measured in quality-adjusted life-years. Others argue that productivity costs should be included in the numerator of the cost-effectiveness ratio, measured in dollars using the friction-cost method or the human-capital method. This paper reviews the productivity-cost controversies and offers suggestions for future research addressing the debated issues.

Psychometric Evaluation of Four HIV Disease—Specific Quality-of-Life Instruments

OBJECTIVE: To provide a comparative evaluation of psychometric properties for three or more HIV disease—specific quality-of-life (QoL) instruments. METHODS: Four instruments were selected using the following criteria: multiple publications of instrument, focus of instrument on QoL, psychometric validation publication or comparison with previously validated questionnaire, stages of HIV/AIDS used or evaluated in the study, and inclusion of sample items or the instrument in at least one publication. The four HIV-specific QoL instruments were: HIV/AIDS-Targeted Quality of Life Instrument, Medical Outcomes Study HIV questionnaire (MOS-HIV), Functional Assessment of Human Immunodeficiency Virus Infection, and HIV Overview of Problems — Evaluation System. These instruments were evaluated using combined criteria derived from McHorney and Tarlov and Shumaker et al. The criteria include: administration, content, depth, reliability, validity, and responsiveness. A letter grade scale (A, B, C, D) was used in rating the criteria. RESULTS: No instrument demonstrated ideal psychometric properties. The MOS-HIV questionnaire was the only instrument that published results for seven of the eight categories. Therefore, a decision cannot be made about the best instrument to use for measuring QoL in an HIV-positive patient. CONCLUSIONS: Published data for these questionnaires had common limitations of sample size, study design, and population demographics. Hence, further testing of these questionnaires is recommended before use in any study to determine suitability, reliability, and validity.

Postcard and Telephone Reminders for Unclaimed Prescriptions: A Comparative Evaluation Using Survival Analysis

OBJECTIVE This study investigated unclaimed prescription reminders with the goal of developing practical and useful recommendations for pharmacies interested in reminding patients to pick up unclaimed prescriptions. Based on the recipient and mode of the reminder notification, this study measured differences in unclaimed prescription pickup time. DESIGN This study was conducted using a convenience sample of three independent pharmacies in a large Midwestern city. A total of 120 subjects with prescriptions remaining unclaimed after 3 or 4 working days were included in the study. Once identified as unclaimed, these prescriptions were randomly assigned into a control group or one of the following four intervention groups: (1) a telephone reminder to the patient, (2) telephone notification to the prescribing physician, (3) a postcard reminder to the patient, and (4) postcard notification to the prescribing physician. RESULTS The results suggest that different methods of pharmacist-initiated reminder systems may affect time to prescription pickup in community pharmacy practice. Marginally significant differences were found among the five study groups and the time to prescription pickup (P = .09). Compared with the control group, neither telephone nor postcard reminders--to patients or physicians--significantly decreased the mean number of days to pickup of potentially abandoned prescriptions. CONCLUSION The actual value of an unclaimed prescription reminder program may reside in improved relationships with customers and with the medical community. The effort and expense of implementing and maintaining an unclaimed prescription reminder system should be balanced against the opportunity to establish and improve pharmacist-patient and pharmacist-physician relationships. Further research in different pharmacy settings should investigate the effectiveness of (1) postcard versus telephone reminders, (2) physician versus patient notification, and (3) the effects of reminders on patient outcomes.

Effect of including (versus excluding) fates worse than death on utility measurement.

OBJECTIVES Most studies typically measure health preferences excluding health states perceived as worse than death. The objective of this study is to test the impact of including (versus excluding) health states perceived to be worse than death on utility measurement using standard gamble (SG) and visual analogue scale (VAS) methods. METHODS By means of a cross-sectional descriptive study design, women were asked to rate the utility of three hypothetical breast cancer health states: cure, treatment, and recurrence (n=119). Preference weights were estimated, allowing for negative utilities with death (perfect health) scaled at zero (1.0). RESULTS Unpaired t-test analysis showed significantly greater change in SG and VAS weights for individuals perceiving cancer recurrence as worse than death than those perceiving death as least desirable state. Excluding negative utilities from the study resulted in significantly smaller changes in utility. Study results show that preference elicitation methods can be successfully adapted to acquire negative utilities. CONCLUSIONS Changes in utility were greater when negative preferences were permitted. Addressing negative preference scores could significantly affect quality adjusted life year estimates in economic analyses.