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To understand the factor structure of health-related quality of life specific to caregivers of people living with traumatic brain injury (TBI). Prospective, cross-sectional data collection. Three TBI Model Systems rehabilitation hospitals, an academic medical center, and a military medical treatment facility. Caregivers (N=558) of people who have sustained a TBI (344 caregivers of civilians and 214 caregivers of service members or veterans; 85% women; 58% spouses; mean age, 46.12±14.07y) who have provided care for an average of 5.82±5.40 years. Not applicable. The Traumatic Brain Injury Caregiver Quality of Life (TBI-CareQOL) measurement system including 10 Patient-Reported Outcomes Measurement Information System item banks (anger, anxiety, depression, social isolation, sleep disturbance, fatigue, ability to participate in social roles and activities, satisfaction with social roles and activities, emotional support, informational support) and 5 TBI-CareQOL banks (feelings of loss–self, feelings of loss–person with TBI, feeling trapped, caregiver-specific anxiety, caregiver strain). Confirmatory factor analysis model fit indices were compared for 14 empirically derived and 5 theoretically derived models. Confirmatory factor analysis results indicated that the best model fit was for a 6-factor model with dimensions that included mental health, social support, social participation, social isolation, physical health, and caregiver emotion. Results indicated that a 6-factor model provided the best model fit for health-related quality of life in caregivers of individuals with TBI. These results have utility for both research and clinical applications. Establishing the TBI-CareQOL's factor structure provides preliminary evidence of the measurement system's construct validity, helps inform the selection of measures for specific research or clinical interventions, and informs the development of composite scores. [ABSTRACT FROM AUTHOR]

PLACE/Ladywell is a block of modular and mobile "pop-up" housing, currently occupying a council owned site awaiting redevelopment in Lewisham, South East London. It houses 24 families on the borough's homelessness register. The development has received multiple awards, been highly praised in the media, and cited by the Greater London Authority as prototypical of pop-up housing as a 'solution' to London's housing crisis. Yet amidst the widespread excitement around PLACE/Ladywell, experiences of urban precarity persist for the families living there. In this paper we examine how resident experiences of being 'on-edge' are defined both by personal crises as they await permanent rehousing, by job losses, evictions and school moves, as well as by anxieties relating to the housing crisis as a wider structure of feeling, including fear after the Grenfell Tower fire and anxieties about gentrification. In doing so, we offer a timely conceptualisation of how experiences of urban precarity persist and mutate in a political moment defined by a growing sense of urgency around finding solutions to the housing crisis. [ABSTRACT FROM AUTHOR]

Abstract Objective To develop a new patient-reported outcome measure that captures feelings of being trapped that are commonly experienced by caregivers of individuals with traumatic brain injury (TBI). Design Cross-sectional. Setting Three TBI Model Systems rehabilitation hospitals, an academic medical center, and a military medical treatment facility. Participants Caregivers (N=560) of civilians with TBI (n=344) and caregivers of service members/veterans with TBI (n=216). Interventions Not applicable. Outcome Measures Traumatic Brain Injury Caregiver Quality of Life (TBI-CareQOL) Feeling Trapped item bank. Results From an initial item pool of 28 items, exploratory and confirmatory factor analyses supported the retention of 16 items. After graded response model (GRM) and differential item functioning analyses were conducted, 15 items were retained in the final measure. GRM calibration data, along with clinical expert input, were used to choose a 6-item, static short form (SF), and the calibration data were used for programming of the TBI-CareQOL Feeling Trapped computer adaptive test (CAT). CAT simulation analyses produced an r =0.99 correlation between CAT scores and the full item bank. Three-week short-form test-retest reliability was very good (r =0.84). Conclusions The new TBI-CareQOL Feeling Trapped item bank was developed to provide a sensitive and efficient examination of the effect that feelings of being trapped, due to the caregiver role, have on health-related quality of life for caregivers of individuals with TBI. Both the CAT and corresponding 6-item SF demonstrate excellent psychometric properties. Future work is needed to establish the responsiveness of this measure to clinical interventions for these caregivers. Highlights • Caregivers of persons with traumatic brain injury often feel trapped. • The Traumatic Brain Injury Caregiver Quality of Life Feeling Trapped item bank was developed to assess quality of life in caregivers. • This new measure addresses an important caregiver emotional concern. [ABSTRACT FROM AUTHOR]

Abstract Objective To develop a new measurement system, the Traumatic Brain Injury Caregiver Quality of Life (TBI-CareQOL), that can evaluate both general and caregiving-specific aspects of health-related quality of life (HRQOL) in caregivers of persons with traumatic brain injury (TBI). Design New item pools were developed and refined using literature reviews, qualitative data from focus groups, and cognitive debriefing with caregivers of civilians and service members/veterans with TBI, as well as expert review, reading level assessment, and translatability review; existing item banks and new item pools were assessed using an online data capture system. Exploratory and confirmatory factor analysis, item response theory, and differential item functioning analyses were utilized to develop new caregiver-specific item banks. Known-groups validity was examined using a series of independent samples t tests comparing caregivers of low-functioning vs high-functioning persons with TBI for each of the new measures, as well as for 10 existing Patient-Reported Outcomes Measurement Information System (PROMIS) measures. Setting Three TBI Model Systems rehabilitation hospitals, an academic medical center, and a military medical treatment facility. Participants Caregivers (N=560) of civilians (n=344) or service members/veterans with TBI (n=216). Interventions Not applicable. Main Outcome Measures The TBI-CareQOL measurement system (including 5 new measures and 10 existing PROMIS measures). Results Exploratory and confirmatory factor analysis, item response theory, and differential item functioning analyses supported the development of 5 new item banks for Feelings of Loss-Self, Feelings of Loss-Person with TBI, Caregiver-Specific Anxiety, Feeling Trapped, and Caregiver Strain. In support of validity, individuals who were caring for low-functioning persons with TBI had significantly worse HRQOL than caregivers that were caring for high-functioning persons with TBI for both the new caregiver-specific HRQOL measures, and for the 10 existing PROMIS measures. Conclusions The TBI-CareQOL includes both validated PROMIS measures and newly developed caregiver-specific measures. Together, these generic and specific measures provide a comprehensive assessment of HRQOL for caregivers of civilians and service members/veterans with TBI. Highlights • The TBI-CareQOL measurement system includes new and existing self-report measures. • Measures were developed specific to caring for someone with traumatic brain injury. • Generic measures also evaluate important quality of life constructs for caregivers. [ABSTRACT FROM AUTHOR]

Abstract Objective To examine the reliability and validity of the short form (SF) and computer adaptive test (CAT) versions of the Patient-Reported Outcomes Measurement Information System (PROMIS) measures of social health of caregivers of civilians and service members/veterans (SMVs) with traumatic brain injury (TBI). Design Self-report questionnaires administered through an online data collection platform. Setting Hospital and community-based outreach at 3 TBI Model Systems rehabilitation hospitals, an academic medical center, and a military medical treatment facility. Participants Caregivers (N=560) (344 civilians and 216 military) of individuals with a documented TBI. Intervention Not applicable. Main Outcome Measures A total of 5 PROMIS social health measures. Results All 5 PROMIS social health measures exceeded the a priori criterion for internal consistency reliability (≥0.70); most PROMIS measures met the criterion for test-retest reliability (≥0.70) in the civilian sample; in the SMV sample, test-retest reliability was generally below this criterion, except for social isolation. For both samples, convergent validity was supported by moderate correlations between the 5 PROMIS social health measures and related measures, and discriminant validity was supported by low correlations between PROMIS social health measures and measures of dissimilar constructs. Most PROMIS scores indicated significantly worse social health in both samples of those caring for individuals who were low functioning. Finally, impairment rates in social health were elevated for those caring for low-functioning individuals, especially in the SMV sample. Conclusions The PROMIS CAT and SF social health measures have potential clinical utility for use in caregivers of civilians and SMVs with TBI. Highlights • Patient-Reported Outcomes Measurement Information System (PROMIS) social health measures are both reliable and valid in caregivers. • PROMIS social health measures are brief (<45s for each measure). • Caring for an individual with a brain injury can significantly affect social health. [ABSTRACT FROM AUTHOR]

Abstract Objectives To establish the reliability and validity of the newly developed TBI-CareQOL patient-reported outcome (PRO) measures in caregivers of civilians and service members/veterans (SMVs) with traumatic brain injury (TBI) so that they can be used with confidence in clinical research and practice. Design Computer-based surveys delivered through an on-line data capture platform. Setting Three TBI Model Systems rehabilitation hospitals, an academic medical center, and a military medical treatment facility. Participants Caregivers (N=560) of individuals with TBI; this included 2 different study samples: 344 caregivers of civilians with TBI and 216 caregivers of SMVs with TBI. Intervention Not Applicable. Main Outcome Measures Five Traumatic Brain Injury Caregiver Quality of Life (TBI-CareQOL) item banks. Results Reliabilities for the TBI-CareQOL measures were excellent (all Cronbach's α >.88); 3-week test-retest reliability ranged from.75 to.90 across the 2 samples. Convergent validity was supported by moderate to high associations among the TBI-CareQOL measures and moderate correlations between the TBI-CareQOL measures and other measures of health-related quality of life (HRQOL) and caregiver burden. Discriminant validity was supported by low correlations between the TBI-CareQOL measures and less-related constructs (eg, caregiver satisfaction). Known-groups validity was supported: caregivers of individuals that were low functioning had worse HRQOL than caregivers of high-functioning individuals. Conclusions Results provide psychometric support for the new TBI-CareQOL item banks. As such, these measures fill a significant gap in the caregiver literature where sensitive PRO measures that capture changes in HRQOL are needed to detect improvements for interventions designed to assist family caregivers. [ABSTRACT FROM AUTHOR]

Abstract Objective To develop a new measure of caregiver strain for use in caregivers of individuals with traumatic brain injury (TBI), Traumatic Brain Injury Caregiver Quality of Life (TBI-CareQOL) Caregiver Strain. Design Qualitative data, literature reviews, and cross-sectional survey study. Setting Three TBI Model Systems rehabilitation hospitals, an academic medical center, and a military medical treatment facility. Participants Caregivers (N=560) of civilians (n=344) or service members/veterans (SMVs) with TBI (n=216). Interventions Not applicable. Main Outcome Measure TBI-CareQOL Caregiver Strain Item Bank. Results Exploratory and confirmatory factor analyses, a graded response model (GRM) and differential item functioning supported the retention of 33 items in the final measure. GRM calibration data was used to inform the selection of a 6-item static short form, and to program the TBI-CareQOL Caregiver Strain computer-adaptive test (CAT). CAT simulation analyses indicated a 0.97 correlation between the CAT scores and the full item-bank. Three-week test-retest reliability was strong (r =0.83). Conclusions The new TBI-CareQOL Caregiver Strain CAT and corresponding 6-item short form were developed using established rigorous measurement development standards; this is the first self-reported measure developed to evaluate caregiver strain in caregivers of individuals with TBI. Highlights • The Traumatic Brain Injury Caregiver Quality of Life (TBI-CareQOL) measurement system includes new and existing self-report measures. • Measures were developed specific to caring for someone with traumatic brain injury. • Generic measures also evaluate important quality of life constructs for caregivers. [ABSTRACT FROM AUTHOR]

Abstract Objective To design a new measure of caregiver-specific anxiety for use in caregivers of individuals with traumatic brain injury (TBI), the Traumatic Brain Injury Caregiver Quality of Life (TBI-CareQOL) Caregiver-Specific Anxiety item bank. Design Cross-sectional survey study. Setting Three TBI Model Systems rehabilitation hospitals, an academic medical center, and a military medical treatment facility. Participants Three hundred forty-four caregivers of civilians with TBI and 216 caregivers of service members/veterans with TBI (N=560). Interventions Not applicable. Main Outcome Measures TBI-CareQOL Caregiver-Specific Anxiety item bank. Results The retention of 40 Caregiver-Specific Anxiety items was supported by exploratory and confirmatory factor analyses. Graded response model (GRM) and differential item functioning analyses supported the retention of 33 items in the final measure. Expert review and GRM calibration data was used to select a 6-item static short form, and GRM calibration data was used to program the TBI-CareQOL Caregiver-Specific Anxiety computer adaptive test (CAT). Conclusions Established, rigorous measurement development standards were used to develop the new TBI-CareQOL Caregiver-Specific Anxiety CAT and corresponding 6-item short form. This measure is the first patient-reported outcome measure designed to assess caregiver-specific anxiety in caregivers of individuals with TBI. The measure exhibits strong psychometric properties. Highlights • Caregivers of persons with traumatic brain injury often have heightened anxiety. • A new self-report measure of caregiver-specific anxiety was developed. • This new measure can help identify caregivers with significant anxiety. [ABSTRACT FROM AUTHOR]

Abstract Objective To develop new patient-reported outcome (PRO) measures to better understand feelings of loss in caregivers of individuals with traumatic brain injury (TBI). Design Cross-sectional survey study. Setting Three TBI Model Systems rehabilitation hospitals, an academic medical center, and a military medical treatment facility. Participants Caregivers (N=560) of civilians with TBI (n=344) or service members/veterans (SMVs) with TBI (n=216). Interventions Not applicable. Main Outcome Measures Traumatic Brain Injury Caregiver Quality of Life (TBI-CareQOL) Feelings of Loss-Self and TBI-CareQOL Feelings of Loss-Person with Traumatic Brain Injury item banks. Results While the initial exploratory and confirmatory factor analyses of the feelings of loss item pool (98 items) potentially supported a unidimensional set of items, further analysis indicated 2 different factors: Feelings of Loss-Self (43 items) and Feelings of Loss-Person with TBI (20 items). For Feelings of Loss-Self, an additional 13 items were deleted due to item-response theory-based item misfit; the remaining 30 items had good overall model fit (comparative fit index [CFI]=0.96, Tucker-Lewis index [TLI]=.96, root mean squared error of approximation [RMSEA]=.10). For Feelings of Loss-Other, 1 additional item was deleted due to an associated high correlated error modification index value; the final 19 items evidenced good overall model fit (CFI=0.97, TLI=.97, RMSEA=.095). The final item banks were developed to be administered as either a Computer Adaptive Test (CAT) or a short-form (SF). Clinical experts approved the content of the 6-item SFs of the 2 measures (3-week test-retest was r =.87 for Feelings of Loss-Self and r =.85 for Feelings of Loss-Person with TBI). Conclusions The findings from this study resulted in the development of 2 new PROs to assess feelings of loss in caregivers of individuals with TBI; TBI-CareQOL Feelings of Loss-Self and TBI-CareQOL Feelings of Loss-Person with TBI. Good psychometric properties were established and an SF was developed for ease of use in clinical situations. Additional research is needed to determine concurrent and predictive validity of these measures in the psychological treatment of those caring for persons with TBI. Highlights • Feelings of loss are common in caregivers of persons with traumatic brain injury. • Two new self-report measures of caregiver feelings of loss were developed. • These self-report measures can help identify feelings of entrapment in caregivers. [ABSTRACT FROM AUTHOR]

Abstract Objective To provide important reliability and validity data to support the use of the Patient-Reported Outcomes Measurement Information System (PROMIS) mental health measures in caregivers of civilians or service members/veterans (SMVs) with traumatic brain injury (TBI). Design Patient-reported outcome surveys administered through an electronic data collection platform. Setting Three TBI model systems rehabilitation hospitals, an academic medical center, and a military medical treatment facility. Participants Caregivers (N=560) of individuals with a documented TBI (344 civilians and 216 military). Intervention Not applicable. Main Outcome Measures PROMIS anxiety, depression, and anger item banks. Results Internal consistency for all the PROMIS Mental Health item banks was very good (all α>.86) and 3-week test-retest reliability was good to adequate (ranged from.65 to.85). Convergent validity and discriminant validity of the PROMIS measures were also supported. Caregivers of individuals who were low functioning had worse emotional health-related quality of life (HRQOL) (as measured by the 3 PROMIS measures) than caregivers of high-functioning individuals, supporting known groups validity. Finally, levels of distress, as measured by the PROMIS measures, were elevated for those caring for low-functioning individuals in both samples (rates ranged from 26.2% to 43.6% for caregivers of low-functioning individuals). Conclusions Results support the reliability and validity of the PROMIS anxiety, depression, and anger item banks in caregivers of civilians and SMVs with TBI. Ultimately, these measures can be used to provide a standardized assessment of HRQOL because it relates to mental health in these caregivers. [ABSTRACT FROM AUTHOR]

Abstract Objective To examine the reliability and validity of Patient-Reported Outcomes Measurement Information System (PROMIS) measures of sleep disturbance and fatigue in traumatic brain injury (TBI) caregivers and to determine the severity of fatigue and sleep disturbance in these caregivers. Design Cross-sectional survey data collected through an online data capture platform. Setting A total of 4 rehabilitation hospitals and Walter Reed National Military Medical Center. Participants Caregivers (N=560) of civilians (n=344) and service member/veterans (SMVs) (n=216) with TBI. Intervention Not applicable. Main Outcome Measures PROMIS sleep and fatigue measures administered as both computerized adaptive tests (CATs) and 4-item short forms (SFs). Results For both samples, floor and ceiling effects for the PROMIS measures were low (<11%), internal consistency was very good (all α≥0.80), and test-retest reliability was acceptable (all r ≥0.70 except for the fatigue CAT in the SMV sample r =0.63). Convergent validity was supported by moderate correlations between the PROMIS and related measures. Discriminant validity was supported by low correlations between PROMIS measures and measures of dissimilar constructs. PROMIS scores indicated significantly worse sleep and fatigue for those caring for someone with high levels versus low levels of impairment. Conclusions Findings support the reliability and validity of the PROMIS CAT and SF measures of sleep disturbance and fatigue in caregivers of civilians and SMVs with TBI. Highlights • The Patient-Reported Outcomes Measurement Information System (PROMIS) sleep and fatigue measures are both reliable and valid. • The PROMIS sleep and fatigue measures are clinically relevant for caregivers. • Caregivers of persons with brain injury have problems with sleep and fatigue. [ABSTRACT FROM AUTHOR]

To describe and compare cohorts between 2 large, longitudinal, federally-funded TBI studies of Service members and veterans across demographic, self-report, and neuropsychological variables. Analysis of data from the DVBIC-TBICoE and LIMBIC-CENC prospective longitudinal studies (PLS). Recruitment locations spanning Department of Defense and Veterans Affairs hospitals across the U.S. 1463 participants (N=1463) enrolled in the DVBIC-TBICoE study and divided among non-injured (NIC) (n=191), injured control (IC) (n=349), mild TBI (mTBI) (n=682), and (severe, moderate, penetrating, and complicated mild traumatic brain injury (smcTBI) (n=241) subgroups. 1550 participants enrolled in the LIMBIC-CENC study and divided between IC (n=285) and mTBI (n=1265) subgroups. IC and mTBI study groups were compared across demographic and military characteristics, self-reported symptoms, and neuropsychological test scores. None. Neurobehavioral Symptom Inventory, PTSD Checklist-Military Version, TBI quality of life, Test of Premorbid Functioning, Wechsler Adult Intelligence Scale-IV Visual Puzzles, Symbol Search, Coding, Letter-Number Sequencing, and Digit Span, Trail Making Test, Delis-Kaplan Executive Functioning System Verbal Fluency, Letter Fluency, and Category Fluency, California Verbal Learning Test-II, and Grooved Pegboard. Compared with DVBIC-TBICoE, LIMBIC-CENC participants have higher enrollment age, education level, proportion of Black race, and time from injury as well as less combat deployments and are less likely to be married. The distribution of military service branches also differed. Further, symptom profiles differed between cohorts. LIMBIC-CENC participants endorsed higher posttraumatic stress disorder symptomatology. DVBIC-TBICoE study IC participants endorsed higher somatosensory and vestibular symptoms (medium effect sizes). Other symptom measure differences had very small effect sizes (≤0.2). Differences were found on many cognitive test results, but are difficult to interpret given the demographic differences and generally very small effect sizes. The heavy use of National Institutes of Health common data elements in both studies and collaboration with the DVBIC-TBICoE study team on development of the LIMBIC-CENC assessment battery enabled this comparative analysis. Results highlight unique differences in study cohorts and add perspective and interpretability for assimilating past and future findings. [ABSTRACT FROM AUTHOR]

Objectives To identify aspects of health-related quality of life (HRQOL) that are relevant to caregivers of individuals with traumatic brain injury (TBI) and to propose an integrated conceptual framework based on this information. Design Nine focus groups with caregivers of individuals with moderate-to-severe TBI were qualitatively analyzed to ascertain the effect that caring for an individual with a TBI has on caregiver HRQOL. Setting University hospitals and rehabilitation treatment centers. Participants Caregivers (N=55) of individuals with moderate-to-severe TBI. Interventions Not applicable. Main Outcome Measures Not applicable. Results Qualitative analysis indicated that caregivers were most concerned about their social health (42% of comments). Other important issues were emotional health (34%), physical health (11%), cognitive health (3%), and feelings of loss (9%; feelings of loss related to changes in the future/potential of the care recipient or related to the caregiver). Areas of concern that were discussed that were specific to the caregiver and not fully evaluated by existing patient-reported outcomes (PROs) included feelings of loss, anxiety related to the caregiver role (reinjury concerns, worry about leaving the person alone, etc), and caregiver strain (burden, stress, feeling overwhelmed, etc). Conclusions Although existing PROs capture relevant aspects of HRQOL for caregivers, there are HRQOL domains that are not addressed. A validated and sensitive HRQOL tool for caregivers of individuals with TBI will facilitate initiatives to improve outcomes in this underserved group. [ABSTRACT FROM AUTHOR]

Abstract: ‘Plates in a basket will rattle’ is a Cambodian proverb which infers that for those who live in the same household, collisions and conflicts between one another are to be expected. Focusing on marital dissolution as one consequence of such discordance, this paper draws on in-depth qualitative research conducted in 2004–2005 and 2011 with ever-married women who have experienced abandonment, separation or divorce in Siem Reap Province. The paper contends that the paucity of scholarly and policy understanding surrounding marital dissolution in Cambodia can also be witnessed in Geography as a disciplinary neglect of theories and empirical instances of domestic rupture. The paper contributes to rectifying this lacuna by reading experiences of marital dissolution through material and symbolic dimensions of domestic space and by opening up discussion on the politics and practices of home ‘unmaking’. [Copyright &y& Elsevier]

Abstract: After decades of turmoil and international isolation, Cambodia has embarked on a threefold transition: from armed conflict to peace, from political authoritarianism to liberal democracy, and from a socialist economic system to one based on market-driven capitalist growth. In this context of transition, the paper explores the perceived linkages that exist between drinking, drunkenness and gender-based violence in rural and urban Siem Reap, home to the global tourism site of Angkor. By considering the ways in which men and women relate alcohol use with violence, the paper questions what implications these social constructions have for tackling gender-based violence and concludes that challenging such external explanations for violence is needed in order for gender-based violence to be understood as the struggle for equality in men and women’s everyday lives. [Copyright &y& Elsevier]

Abstract: In 2003 the World Calibration Centre for volatile organic compounds (WCC-VOC) which forms part of the Global Atmosphere Watch (GAW) program coordinated the first comprehensive intercomparison exercise among the GAW-VOC community. The intercomparison focused on a synthetic C2–C11 VOC standard mixture in nitrogen (N2) and involved nine different stations/laboratories (10 instruments) from seven countries (Brazil, Canada [two labs], Czech Republic, Finland, Germany [two labs; three instruments], Ireland, and Slovakia), representing four measurement programs (GAW, EMEP, CAPMoN, LBA). These sites either run canister or online measurements. WCC-VOC provided each participant of the intercomparison exercise with standard gas canisters which contained 73 VOCs prepared and certified by the National Center for Atmospheric Research (NCAR), Boulder. The participating laboratories were expected to identify and quantify as many compounds of the WCC-VOC standard canister as possible based on their routine identification and calibration methods. The primary objective of this first intercomparison was to examine the current performance status of the analytical facilities of each laboratory and to check whether the results meet the Data Quality Objectives (DQO) developed by WCC-VOC. An additional objective was to establish a ranking of properly determined compounds among all laboratories in order to identify compounds which could be most accurately determined by all laboratories. Due to the variety of sampling and analytical methods among the participants both the number of identified species (16–150 VOCs) and their proper quantification differed largely. Focusing on a subset of 28 VOCs recognized as primary GAW target compounds the results show that the DQOs for repeatability are met in most cases. However for the deviation from the WCC-VOC reference values the picture is different. For some VOCs the concentrations differed significantly among the different laboratories. In terms of both uncertainty and repeatability a significant number of atmospherically relevant VOCs (e.g. propane, propylene, isoprene, and benzene) are properly determined by most labs. However, difficulties occur with other important VOCs (e.g. acetylene, i-pentane, toluene). From this subset of VOC results it appears imperative to strengthen harmonization procedures particular with regard to real air samplings. These processes have been initiated and include more frequent intercomparisons also covering ambient air samples, individual performance audits, and a future networkwide calibration standard. [Copyright &y& Elsevier]