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Unlabelled: Pain complaints are commonly reported symptoms among postmenopausal women and can have significant effects on health-related quality of life. We sought to identify medical and psychosocial factors that predict changes in pain and overall physical functioning over a 3-year period among postmenopausal women with recurrent pain conditions. We examined data from postmenopausal women age 50 to 79 with recurrent pain conditions (low back pain, neck pain, headache or migraines, or joint pain or stiffness) over a 3-year period using the Women's Health Initiative Observational Study Cohort (N = 67,963). Multinomial logistic regression models controlling for demographic and clinical characteristics were used to identify baseline predictors of change in the SF-36 subscales for pain and physical functioning between baseline and 3-year follow-up. Body mass index (BMI) was associated with worsening of pain (OR [95% CI] 1.54 [1.45-1.63] for BMI ≥30) and physical functioning (1.83 [1.71-1.95] for BMI ≥30). A higher reported number of nonpain symptoms, higher medical comorbidity, and a positive screen for depression (1.13 [1.05-1.22] for worsened pain) were also associated with worsening of pain and physical functioning. Baseline prescription opioid use was also associated with lack of improvement in pain (OR .42, 95% CI .36-.49) and with worsened physical functioning (1.25 [1.04-1.51]).Perspective: This study presents prospective data on change in pain and physical functioning in postmenopausal women over a 3-year period. Our results suggest depression, nonpain physical symptoms, obesity, and possibly opioid treatment are associated with worse long-term pain outcomes in this population. [ABSTRACT FROM AUTHOR]

Objective: The objective was to explore and describe the role of pharmacists in providing postdischarge care to patients with kidney disease., Data Sources: PubMed, Embase (Elsevier), CINAHL (Ebscohost), Web of Science Core Collection, and Scopus were searched on January 30, 2023. Publication date limits were not included. Search terms were identified based on 3 concepts: kidney disease, pharmacy services, and patient discharge. Experimental, quasi-experimental, observational, and qualitative studies, or study protocols, describing the pharmacist's role in providing postdischarge care for patients with kidney disease, excluding kidney transplant recipients, were eligible., Study Selection and Data Extraction: Six unique interventions were described in 10 studies meeting inclusion criteria., Data Synthesis: Four interventions targeted patients with acute kidney injury (AKI) during hospitalization and 2 evaluated patients with pre-existing chronic kidney disease. Pharmacists were a multidisciplinary care team (MDCT) member in 5 interventions and were the sole provider in 1. Roles commonly identified include medication review, medication reconciliation, medication action plan formation, kidney function assessment, drug dose adjustments, and disease education. Some studies showed improvements in diagnostic coding, laboratory monitoring, medication therapy problem (MTP) resolution, and patient education; prevention of hospital readmission was inconsistent. Limitations include lack of standardized reporting of kidney disease, transitions of care processes, and differences in outcomes evaluated., Relevance to Patient Care and Clinical Practice: This review identifies potential roles of a pharmacist as part of a postdischarge MDCT for patients with varying degrees of kidney disease., Conclusions: The pharmacist's role in providing postdischarge care to patients with kidney disease is inconsistent. Multidisciplinary care teams including a pharmacist provided consistent identification and resolution of MTPs, improved patient education, and increased self-awareness of diagnosis., Competing Interests: Declaration of Conflicting InterestsThe authors declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: MMM, JWS, JBR, JLW, RM, and EO have nothing to disclose. EFB is supported by a grant from the National Institute of Allergy and Infectious Diseases (K23AI143882). The funding source had no role in this manuscript and its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIH. Consulting relationship with Wolters-Kluwer. SKG is supported by grants from the National Institute of Diabetes and Digestive and Kidney Diseases R01DK121730 and U01DK130010, the National Center for Complementary and Integrative Health U54AT008909, and the Jewish Healthcare Foundation. SKG holds an executive position in the Society of Critical Care Medicine. The content of this manuscript is solely the responsibility of the author and does not represent the official views of the Society of Critical Care Medicine. EDS Personal fees for service on the editorial board for the Clinical Journal of the American Society of Nephrology, royalties as an author for UptoDate, and consulting agreement with Novartis Pharmaceutics for DSMB service. SAS discloses the following speaking fees from Baxter Canada, consulting from AstraZeneca, and honorarium from Otsuka and Novo Nordisk. JAN is supported by grants from NIDDK (R01DK128208, R01DK133539, U01DK12998, and U54DK137307).

Objectives: To describe trends in suicides with opioid poisoning noted as a contributing cause of death., Methods: Using National Vital Statistics data (1999-2014), we calculated age-adjusted rates of suicide with opioid poisoning (International Classification of Diseases, Tenth Revision codes T40.0-T40.4) per 100 000 population per year and annual percentage change (APC) in rates. We used Joinpoint regression to examine trends in suicide rates and proportion of suicides involving opioids., Results: The annual age-adjusted death rate from suicide with opioid poisoning as a contributing cause of death increased from 0.3 per 100 000 in 1999 to 0.7 per 100 000 in 2009 (APC = 8.1%; P < .001), and remained at 0.6 to 0.7 per 100 000 through 2014. The percentage of all suicides with opioid poisoning listed as a contributing cause of death increased from 2.2% in 1999 to 4.4% in 2010 (P < .001). Rates were similar for men and women, higher among Whites than non-Whites, higher in the West, and highest for individuals aged 45 to 64 years., Conclusions: Opioid involvement in suicides has doubled since 1999. These analyses underscore the need for health care providers to assess suicidal risk in patients receiving opioids.

Objective: Increasing rates of opioid use disorders (OUDs) (abuse and dependence) among patients prescribed opioids are a significant public health concern. We investigated the association between exposure to prescription opioids and incident OUDs among individuals with a new episode of a chronic noncancer pain (CNCP) condition., Methods: We utilized claims data from the HealthCore Database for 2000 to 2005. The dataset included all individuals aged 18 and over with a new CNCP episode (no diagnosis in the prior 6 mo), and no opioid use or OUD in the prior 6 months (n=568,640). We constructed a single multinomial variable describing prescription on opioid days supply (none, acute, and chronic) and average daily dose (none, low dose, medium dose, and high dose), and examined the association between this variable and an incident OUD diagnosis., Results: Patients with CNCP prescribed opioids had significantly higher rates of OUDs compared with those not prescribed opioids. Effects varied by average daily dose and days supply: low dose, acute (odds ratio [OR]=3.03; 95% confidence interval [CI], 2.32, 3.95); low dose, chronic (OR=14.92; 95% CI, 10.38, 21.46); medium dose, acute (OR=2.80; 95% CI, 2.12, 3.71); medium dose, chronic (OR=28.69; 95% CI, 20.02, 41.13); high dose, acute (OR=3.10; 95% CI, 1.67, 5.77); and high dose, chronic (OR=122.45; 95% CI, 72.79, 205.99)., Conclusions: Among individuals with a new CNCP episode, prescription opioid exposure was a strong risk factor for incident OUDs; magnitudes of effects were large. Duration of opioid therapy was more important than daily dose in determining OUD risk.

Objective: To report chronic opioid therapy discontinuation rates after five years and identify factors associated with discontinuation., Methods: Medical and pharmacy claims records from January 2000 through December 2005 from a national private health network (HealthCore), and Arkansas (AR) Medicaid were used to identify ambulatory adult enrollees who had 90 days of opioids supplied. Recipients were followed until they discontinued opioid prescription fills or disenrolled. Kaplan Meier survival models and Cox proportional hazards models were estimated to identify factors associated with time until opioid discontinuation., Results: There were 23,419 and 6,848 chronic opioid recipients followed for a mean of 1.9 and 2.3 years in the HealthCore and AR Medicaid samples. Over a maximum follow up of 4.8 years, 67.0% of HealthCore and 64.9% AR Medicaid recipients remained on opioids. Recipients on high daily opioid dose (greater than 120 milligrams morphine equivalent (MED)) were less likely to discontinue than recipients taking lower doses: HealthCore hazard ratio (HR) = 0.66 (95%CI: 0.57-0.76), AR Medicaid HR = 0.66 (95%CI: 0.50-0.82). Recipients with possible opioid misuse were also less likely to discontinue: HealthCore HR = 0.83 (95%CI: 0.78-0.89), AR Medicaid HR = 0.78 (95%CI: 0.67-0.90)., Conclusions: Over half of persons receiving 90 days of continuous opioid therapy remain on opioids years later. Factors most strongly associated with continuation were intermittent prior opioid exposure, daily opioid dose ≥ 120 mg MED, and possible opioid misuse. Since high dose and opioid misuse have been shown to increase the risk of adverse outcomes special caution is warranted when prescribing more than 90 days of opioid therapy in these patients.

Objective: To estimate the prevalence of and risk factors for opioid abuse/dependence in long-term users of opioids for chronic pain, including risk factors for opioid abuse/dependence that can potentially be modified to decrease the likelihood of opioid abuse/dependence, and non-modifiable risk factors for opioid abuse/dependence that may be useful for risk stratification when considering prescribing opioids., Methods: We used claims data from two disparate populations, one national, commercially insured population (HealthCore) and one state-based, publicly insured (Arkansas Medicaid). Among users of chronic opioid therapy, we regressed claims-based diagnoses of opioid abuse/dependence on patient characteristics, including physical health, mental health and substance abuse diagnoses, sociodemographic factors, and pharmacological risk factors., Results: Among users of chronic opioid therapy, 3% of both the HealthCore and Arkansas Medicaid samples had a claims-based opioid abuse/dependence diagnosis. There was a strong inverse relationship between age and a diagnosis of opioid abuse/dependence. Mental health and substance use disorders were associated with an increased risk of opioid abuse/dependence. Effects of substance use disorders were especially strong, although mental health disorders were more common. Concerning opioid exposure; lower days supply, lower average doses, and use of Schedule III-IV opioids only, were all associated with lower likelihood of a diagnosis of opioid abuse/dependence., Conclusion: Opioid abuse and dependence are diagnosed in a small minority of patients receiving chronic opioid therapy, but this may under-estimate actual misuse. Characteristics of the patients and of the opioid therapy itself are associated with the risk of abuse and dependence., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Background: There has been an increase in overdose deaths and emergency department visits (EDVs) involving use of prescription opioids, but the association between opioid prescribing and adverse outcomes is unclear., Methods: Data were obtained from administrative claim records from Arkansas Medicaid and HealthCore commercially insured enrollees, 18 years and older, who used prescription opioids for at least 90 continuous days within a 6-month period between 2000 and 2005 and had no cancer diagnoses. Regression analysis was used to examine risk factors for EDVs and alcohol- or drug-related encounters (ADEs) in the 12 months following 90 days or more of prescribed opioids., Results: Headache, back pain, and preexisting substance use disorders were significantly associated with EDVs and ADEs. Mental health disorders were associated with EDVs in HealthCore enrollees and with ADEs in both samples. Opioid dose per day was not consistently associated with EDVs but doubled the risk of ADEs at morphine-equivalent doses over 120 mg/d. Use of short-acting Drug Enforcement Agency Schedule II opioids was associated with EDVs compared with use of non-Schedule II opioids alone (relative risk range, 1.09-1.74). Use of Schedule II long-acting opioids was strongly associated with ADEs (relative risk range, 1.64-4.00)., Conclusions: Use of Schedule II opioids, headache, back pain, and substance use disorders are associated with EDVs and ADEs among adults prescribed opioids for 90 days or more. It may be possible to increase the safety of chronic opioid therapy by minimizing the prescription of Schedule II opioids in these higher-risk recipients.

The use of chronic opioid therapy (COT) for chronic non-cancer pain (CNCP) has increased dramatically in the past two decades. There has also been a marked increase in the abuse of prescribed opioids and in accidental opioid overdose. Misuse of prescribed opioids may link these trends, but has thus far only been studied in small clinical samples. We therefore sought to validate an administrative indicator of opioid misuse among large samples of recipients of COT and determine the demographic, clinical, and pharmacological risks associated with possible and probable opioid misuse. A total of 21,685 enrollees in commercial insurance plans and 10,159 in Arkansas Medicaid who had at least 90 days of continuous opioid use 2000-2005 were studied for one year. Criteria were developed for possible and probable opioid misuse using administrative claims data concerning excess days supplied of short-acting and long-acting opioids, opioid prescribers and opioid pharmacies. We estimated possible misuse at 24% of COT recipients in the commercially insured sample and 20% in the Medicaid sample and probable misuse at 6% in commercially insured and at 3% in Medicaid. Among non-modifiable factors, younger age, back pain, multiple pain complaints and substance abuse disorders identify patients at high risk for misuse. Among modifiable factors, treatment with high daily dose opioids (especially >120 mg MED per day) and short-acting Schedule II opioids appears to increase the risk of misuse. The consistency of the findings across diverse patient populations and the varying levels of misuse suggest that these results will generalize broadly, but await confirmation in other studies., (Copyright (c) 2010 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.)

Context: Although opioids are increasingly used for chronic noncancer pain (CNCP), we know little about opioid dosing patterns among individuals with CNCP in usual care settings, and how these are changing over time., Objectives: To investigate the distribution of mean daily dose and mean days supply among patients with CNCP in two disparate populations, one national and commercially insured population (HealthCore) and one state based and publicly insured (Arkansas Medicaid), for years 2000 and 2005., Methods: For individuals with any opioid use, we calculated the distribution of mean daily dose (in milligram morphine equivalents), mean days supply in a year, mean annual dose, and patient characteristics associated with heavy utilizers of opioids., Results: Between 2000 and 2005, across all percentiles, there was little change in the mean daily opioid dose. In HealthCore, mean days supply increased most rapidly at the top end of the days supply distribution, whereas in Arkansas Medicaid, the greatest increases were near the median of days supply. In HealthCore, the top 5% of users accounted for 70% of total use (measured in milligram morphine equivalents), and the top 5% of Arkansas Medicaid users accounted for 48% of total use. The likelihood of heavy opioid utilization was increased among individuals with multiple pain conditions, and in HealthCore, among those with mental health and substance use disorders., Conclusion: Opioid use is heavily concentrated among a small percent of patients. The characteristics of these high utilizers need to be further established, and the benefits and risks of their treatment evaluated., (Copyright (c) 2010 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.)

Background: Opioids have been linked to increased risk of fractures, but little is known about how opioid dose affects fracture risk., Objective: To assess whether risk of fracture increases with opioid dose among older patients initiating sustained use of opioids for chronic non-cancer pain., Design: A cohort study that uses Cox proportional hazards models to compare fracture risk among current opioid users vs. persons no longer using opioids., Participants: Members of an integrated health care plan (N = 2,341) age 60 years and older who received 3+ opioid prescriptions within a 90-day period for chronic, non-cancer pain between 2000 and 2005., Measurements: Time-varying measures of opioid use and average daily dose in morphine equivalents were calculated from automated data. Fractures were identified from automated data and then validated through medical record review., Results: Compared with persons not currently using opioids, opioid use was associated with a trend towards increased fracture risk (1.28 (95% CI (0.99, 1.64 )). Higher dose opioid use (>or=50 mg/day) was associated with a 9.95% annual fracture rate and a twofold increase in fracture risk (2.00 (95% CI (1.24, 3.24)). Of the fractures in the study cohort, 34% were of the hip or pelvis, and 37% were associated with inpatient care., Conclusions: Higher doses (>or=50 mg/day) of opioids for chronic non-cancer pain were associated with a 2.00 increase in risk of fracture confirmed by medical record review. Clinicians should consider fracture risk when prescribing higher-dose opioid therapy for older adults.

Objective: To estimate recent age- and sex-specific changes in long-term opioid prescription among patients with chronic pain in two large American Health Systems., Design: Analysis of administrative pharmacy data to calculate changes in prevalence of long-term opioid prescription (90 days or more during a calendar year) from 2000 to 2005, within groups based on sex and age (18-44, 45-64, and 65 years and older). Separate analyses were conducted for patients with and without a diagnosis of a mood disorder or anxiety disorder. Changes in mean dose between 2000 and 2005 were estimated, as were changes in the rate of prescription for different opioid types (short-acting, long-acting, and non-Schedule 2)., Patients: Enrollees in HealthCore (N = 2,716,163 in 2000) and Arkansas Medicaid (N = 115,914 in 2000)., Results: Within each of the age and sex groups, less than 10% of patients with a chronic pain diagnosis in HealthCore, and less than 33% in Arkansas Medicaid, received long-term opioid prescriptions. All age, sex, and anxiety/depression groups showed similar and statistically significant increases in long-term opioid prescription between 2000 and 2005 (35-50% increase). Per-patient daily doses did not increase., Conclusions: No one group showed especially large increases in long-term opioid prescriptions between 2000 and 2005. These results argue against a recent epidemic of opioid prescribing. These trends may result from increased attention to pain in clinical settings, policy or economic changes, or provider and patient openness to opioid therapy. The risks and benefits to patients of these changes are not yet established.

Objective: We report trends in long-term opioid use among patients with a history of depression from two large health plans., Methods: Using claims data, age- and gender-adjusted rates for long-term (>90 days) opioid use episodes were calculated for 1997-2005, comparing those with and without a depression diagnosis in the prior 2 years. Opioid use characteristics were calculated for those with a long-term episode in 2005., Results: Incident and prevalent long-term opioid use rates were three times higher in those with a history of depression. Prevalent long-term use per 1000 in patients with a history of depression increased from 69.8 to 125.9 at Group Health and from 84.3 to 117.5 at Kaiser Permanente of Northern California between 1997 and 2005. Those with a history of depression were more likely to receive a higher average daily dose, greater days supply, and Schedule II opioids than nondepressed persons., Conclusion: Persons with a history of depression are more likely to receive long-term opioid therapy for noncancer pain than those without a history of depression. Results suggest that long-term opioid therapy for noncancer pain is being prescribed to a different population in clinical practice than the clinical trial populations where opioid efficacy has been established.

Unlabelled: We sought to examine whether the presence of a noncancer pain condition is independently associated with an increased risk for suicidal ideation, plan, or attempt after adjusting for sociodemographic and psychiatric risk factors for suicide and whether risk differs by specific type of pain. We analyzed data from the National Comorbidity Survey Replication, a household survey of U.S. civilian adults age 18 years and older (n = 5692 respondents). Pain conditions, nonpain medical conditions, and suicidal history were obtained by self-report. DSM-IV mood, anxiety, and substance use disorders were assessed using the World Health Organization's Composite International Diagnostic Interview. Antisocial and borderline personality traits were assessed with the International Personality Disorder Examination screening questionnaire. In unadjusted logistic regression analyses, the presence of any pain condition was associated with lifetime and 12-month suicidal ideation, plan, and attempt. After controlling for demographic, medical, and mental health covariates, the presence of any pain condition remained significantly associated with lifetime suicidal ideation (odds ratio, 1.4; 95% confidence interval, 1.1-1.8) and plan. Among pain subtypes, severe or frequent headaches and "other" chronic pain remained significantly associated with lifetime suicidal ideation and plan; "other" chronic pain was also associated with attempt., Perspective: The risk for suicidal thoughts and behaviors that may accompany back, neck, and joint pain can be accounted for by comorbid mental health disorders. There may be additional risk accompanying frequent headaches and "other" chronic pain that is secondary to psychosocial processes not captured by the mental disorders assessed.

Unlabelled: Use of prescription opioids for noncancer pain has increased significantly in recent years, but it is not known if trends differ among the most common noncancer pain conditions. We examined trends in opioid prescribing for the years 2000 through 2005 for individuals with arthritis/joint pain, back pain, neck pain, and headaches by type and number of pain diagnoses, using data from claims records from 2 health insurers: HealthCore commercially insured members (N = 3,768,223) and Arkansas Medicaid (N = 127,866). Rates of headache, back pain, and neck pain diagnoses increased significantly in Arkansas Medicaid enrollees but more modestly among HealthCore enrollees. Rates of opioid use increased in both groups, with long-term use (>90 days' supply per year) increasing at twice the rate of any use. Rates of opioid use did not differ widely between noncancer pain conditions, but long-term opioid use rates doubled with each additional pain diagnosis. Mean days supply and cumulative yearly dose increased between 2000 and 2005 for all pain types and with increasing number of pain diagnoses, but dose per day supply remained relatively stable. The greatest increases in dose among all the pain conditions were seen in short-acting DEA Schedule II opioids., Perspective: This study demonstrates increased use of opioids, particularly long-term use, in noncancer pain over a 6-year period among those with multiple pain types. These results appear to reflect a general increase in use of prescription opioids for noncancer pain rather than a condition-specific change in prescribing practices.

Opioids are widely prescribed for non-cancer pain conditions (NCPC), but there have been no large observational studies in actual clinical practice assessing patterns of opioid use over extended periods of time. The TROUP (Trends and Risks of Opioid Use for Pain) study reports on trends in opioid therapy for NCPC in two disparate populations, one national and commercially insured population (HealthCore plan data) and one state-based and publicly-insured (Arkansas Medicaid) population over a six year period (2000-2005). We track enrollees with the four most common NCPC conditions: arthritis/joint pain, back pain, neck pain, headaches, as well as HIV/AIDS. Rates of NCPC diagnosis and opioid use increased linearly during this period in both groups, with the Medicaid group starting at higher rates and the HealthCore group increasing more rapidly. The proportion of enrollees receiving NCPC diagnoses increased (HealthCore 33%, Medicaid 9%), as did the proportion of enrollees with NCPC diagnoses who received opioids (HealthCore 58%, Medicaid 29%). Cumulative yearly opioid dose (in mg. morphine equivalents) received by NCPC patients treated with opioids increased (HealthCore 38%, Medicaid 37%) due to increases in number of days supplied rather than dose per day supplied. Use of short-acting Drug Enforcement Administration Schedule II opioids increased most rapidly, both in proportion of NCPC patients treated (HealthCore 54%, Medicaid 38%) and in cumulative yearly dose (HealthCore 95%, Medicaid 191%). These trends have occurred without any significant change in the underlying population prevalence of NCPC or new evidence of the efficacy of long-term opioid therapy and thus likely represent a broad-based shift in opioid treatment philosophy.

Objective: This study examined the independent and interactive effects of common mental disorders and chronic pain conditions on employment and work outcomes among individuals under 65 years old., Methods: Cross-sectional data were analyzed from the second wave of Healthcare for Communities (HCC2), a household telephone survey of U.S. civilian adults conducted in 2000-2001 (N=5,328). Common mental disorders were assessed by using the short-form version of the World Health Organization's Composite International Diagnostic Interview. Chronic pain conditions and employment outcomes were identified by self-report. Logistic and linear regression analyses were used to provide estimates for work impairment on the basis of the presence of a mental disorder or a chronic pain condition or both., Results: The interaction between presence of a mental disorder and presence of a chronic pain condition was significantly associated with no work for pay in the past 12 months (odds ratio=2.3, 95% confidence interval=1.2-4.2) and number of days of work missed in the past month because of health (regression coefficient=1.47, SE=.59). In stratified analyses this effect persisted for women but not for men. The presence of a mental disorder and the presence of a chronic pain condition were each independently associated with limitations in work and any work missed in the past 30 days because of health, although the interaction was not significant., Conclusions: Mental disorders and chronic pain are each associated with work disability. Mental disorders are more strongly associated with some work disability outcomes when they are accompanied by chronic pain, especially among women.

Objective: Mental health disorders commonly co-occur in patients with chronic pain, but little is known about the role of chronic pain in mental health service use. In this study, the authors explored the role of chronic pain in mental health service use by adults according to age group., Method: The authors conducted a cross-sectional analysis of survey data from the second wave of the Health Care for Communities telephone survey collected in 2000-2001. Participants consisted of U.S. civilian adults (N = 6629) from randomly selected U.S. households. Common mental disorders were assessed using the short-form versions of the World Health Organization's Composite International Diagnostic Interview. Chronic pain conditions and mental health services received were identified by self-report. Physical and mental functioning was assessed using the Short Form-12., Results: Adults older than age 60 had higher rates of chronic pain and lower rates of mental health service use compared with those aged 18-60 years. In multiple logistic regression models, an interaction effect was found between age and chronic pain (odds ratio: 3.0 [1.1-8.0]) with chronic pain significantly increasing the odds of any mental health care in the past year in adults older than 60 years of age., Conclusions: Chronic pain increases the likelihood of mental health service use among older adults. Chronic pain may facilitate the presentation of distress in medical settings for these adults.

The Federal Aviation Administration's effort to automate air traffic control (ATC) requires that the functionality provided today be captured in future systems. We report the first quantitative naturalistic observation of paper flight progress strip interactions during operational use. Strip use was similar in a variety of situations, but some uses varied as a function of altitude, staffing, or the cooperative style used by controller teams. Design of automation should proceed by prioritizing changes based on frequency of use and importance and should ensure that an effective method of interacting with flight information is incorporated. In addition to applied relevance to the ATC domain, the results touch on several theoretical concerns relevant to dynamic environments. Actual and potential applications of this research include the establishment of a database of strip activity and an arsenal of information valuable to system designers.

Market-type mechanisms have been introduced and are being explored for various environmental programs. Several existing programs, however, have not attained the cost savings that were initially projected. Modeling that acknowledges the role of transactions costs and the discrete, bilateral, and sequential manner in which trades are executed should provide a more realistic basis for calculating potential cost savings. This paper presents empirical evidence on potential cost savings by examining a market for the abatement of sediment from farmland. Empirical results based on a market simulation model find no statistically significant change in mean abatement costs under several transaction cost levels when contracts are randomly executed. An alternative method of contract execution, gain-ranked, yields similar results. At the highest transaction cost level studied, trading reduces the total cost of compliance relative to a uniform standard that reflects current regulations.