Impact of a pharmacist-led oral chemotherapy monitoring clinic at the South Texas Veterans Health Care System.

As cancer treatments shift from traditional intravenous chemotherapy to inclusion of oral oncolytics, there is a critical need for structured oral chemotherapy monitoring and follow-up programs. To provide continuous care and minimize clinical gaps to Veterans receiving oral chemotherapy, the hematology/oncology clinical pharmacy practitioners designed and initiated a pilot, pharmacist-driven, Oral Chemotherapy Monitoring Clinic at the South Texas Veterans Health Care System supported by an oral chemotherapy certified pharmacy technician. A retrospective evaluation of patients receiving oral chemotherapy at the South Texas Veterans Health Care System was performed before (Phase I) and after (Phase II) pilot implementation to assess the impact of an Oral Chemotherapy Monitoring Clinic on compliance with drug-specific lab and symptom monitoring. Complete monitoring was defined as 100% of recommended labs and symptoms assessed per cycle, partial monitoring was <100%, but >0%, and incomplete monitoring was defined as 0%. The primary outcome assessed the proportion of patients receiving complete monitoring in Phase II compared to Phase I. Most patients were male (94%), with a median age of 72 years. The most common oncolytic was abiraterone acetate. Overall, drug-specific baseline and follow-up laboratory and symptom monitoring was complete at a statistically significantly higher rate in Phase II compared with Phase I (p-value < 0.01). A significantly higher portion of patients in the Phase II cohort had a clinical pharmacy practitioner intervention (44% vs. 90%; p < 0.01). Monitoring for Veterans receiving oral chemotherapy was optimized with clinical pharmacy practitioner and certified pharmacy technician involvement while simultaneously alleviating Oncologist and nurse oral chemotherapy workload.

Premix versus On-Demand Workflow Models in a Veterans Affairs Hematology/Oncology Pharmacy: Impact on Estimated Waste Costs and Patient Wait Time.

Background: The balance between reducing patient wait time and mitigating waste of parenteral products has not been well described in literature. Objective: Evaluate the patient wait times and cost-effectiveness of employing a premix versus an on-demand workflow model for compounding parenteral admixtures in a hematology/oncology infusion setting. Methods: This single center, retrospective cost analysis compiled manually documented monthly waste reports and estimated drug pricing for the institution to calculate the cost of waste during both premix and on-demand compounding workflows. Time to administration was audited for one week with both models. Results: Over a period of 28.5 months following the premix model, 564 products were documented as wasted ($1,196,014.01 in estimated drug purchasing cost). Over a period of 3 months following the on-demand model, 12 products were wasted ($34,823.98 in estimated drug purchasing cost). Switching models reduced the monthly average number of wasted products from 20 to 4 per month; the average cost of waste was reduced from $41,965.40 to $11,607.99 per month (P < .0001). Overall patient wait time from clearance until administration, excluding any recommended wait times after premedication administration (if applicable), was similar in both models: an average of 38.26 minutes in the premix model and 40.97 minutes in the on-demand model. Conclusion: Premixing parenteral admixtures was not cost effective at our institution. After resuming an on-demand compounding model, the monthly cost of waste (based on drug pricing alone) was reduced by over 70%. The wait time from clearance to treatment administration was similar in both models.

Outcomes in Patients With Curative Malignancies Receiving Filgrastim as Primary Prophylaxis.

Background: Granulocyte colony-stimulating factor prophylaxis has been shown to reduce the risk and duration of chemotherapy-induced neutropenia and febrile neutropenia and is recommended for at-risk patients receiving chemotherapy. Within the South Texas Veterans Health Care System, daily filgrastim injections remain the preferred formulation of granulocyte colony-stimulating factor for primary prophylaxis of febrile neutropenia. Methods: This retrospective, single-center cohort study included 59 patients who received daily filgrastim as primary prophylaxis with a curative cancer diagnosis and a chemotherapy regimen at the South Texas Veterans Health Care System from September 1, 2015 to September 24, 2020. Patients had either a high risk for febrile neutropenia or a chemotherapy regimen with an intermediate risk for febrile neutropenia and additional risk factors. The primary outcome was the incidence of neutropenia/febrile neutropenia leading to treatment delays. Secondary outcomes included chemotherapy dose decreases or discontinuations, hospitalizations, days of hospitalization, infections, extended duration of filgrastim, and transitions to pegfilgrastim due to neutropenia/febrile neutropenia. Results: Patients received a median (IQR) of 7 (5-10) doses of filgrastim for primary prophylaxis. Overall, 10 patients (17%) experienced treatment delays due to neutropenia/febrile neutropenia. Fifteen patients (25%) were hospitalized with a median (IQR) length of stay of 5 (4-7) days, 9 patients (15%) had documented infections, and 2 patients (3%) required a chemotherapy dose reduction. Additionally, 9 patients (15%) required an additional median (IQR) of 2 (2-5) doses of filgrastim, and 9 (15%) patients were transitioned to pegfilgrastim. Conclusions: These results suggest that additional measures such as tracking postnadir absolute neutrophil counts should be performed to ensure patients receive an appropriate number of filgrastim doses to prevent complications associated with neutropenia/febrile neutropenia.

Incidence of invasive fungal infections in patients with chronic lymphocytic leukemia receiving ibrutinib within the veteran's healthcare administration.

PURPOSE: Ibrutinib is a tyrosine kinase inhibitor that is increasingly prescribed in chronic lymphocytic leukemia (CLL). Invasive fungal infections (IFIs) have been reported early after ibrutinib initiation. Timing of IFIs is within 6 months and commonly reported fungal infections include Cryptococcus, Aspergillus, and Pneumocystis. Currently, there are no recommendations for routine prophylaxis against IFIs in patients receiving ibrutinib for CLL. OBJECTIVE: The objective of this study was to evaluate the incidence of IFIs in patients receiving ibrutinib for CLL in first-line and relapsed/refractory (R/R) settings. METHODS: This was a retrospective, cohort study of patients diagnosed with CLL and initiated on ibrutinib in the Veterans Health Administration (VHA) from October 1, 2013 to March 31, 2018. Patients were included if diagnosed with a proven or probable IFI from the start date of ibrutinib to 30 days after the last dose of ibrutinib. RESULTS: Fourteen out of 1069 patients met inclusion criteria for IFI while on ibrutinib for CLL. All patients included were male with a median age of 78 years. Fifty percent of patients were initiated on ibrutinib within 3 months of last chemotherapy. IFIs occurred within 3 months (50%) and 6 months (71%) of ibrutinib initiation. Seventy-one percent of patients were continued on ibrutinib with concurrent IFI diagnosis. CONCLUSION: The reported IFI incidence of 1.3% is comparable to current estimates of 1.2%. Future studies should examine the relationship of ibrutinib and incidence of IFIs in first-line and R/R settings in addition to identifying clinical risk factors predisposing patients to IFIs.

Long-Distance Caregivers: What are Their Experiences with Formal Care Providers?

OBJECTIVES: Extensive literature has documented the experiences of informal caregivers and their interactions with formal care providers, yet this research is almost entirely limited to caregivers who live near their care-recipients. This study aims to describe long-distance caregivers' (LDC) experiences (e.g., satisfaction and challenges) with formal care providers. Subgroup differences were examined based on the care-recipient's (CR) dementia status and residential setting (community versus residential care). METHODS: Data were collected from 296 LDCs (Mage = 56.64, SD = 12.40) categorized into four subgroups based on CR dementia status and residential setting. Participants rated their overall satisfaction, satisfaction with communication and information, and described challenges faced in their interactions with formal care providers. RESULTS: Challenges related to formal care providers were significantly greater and satisfaction significantly lower among LDCs of CRs in residential care, irrespective of dementia status, when compared to LDCs of CRs in the community. CONCLUSIONS: This study provides insights into the experiences of a growing segment of the caregiver population managing care from a distance, specifically in their interactions with formal care providers. CLINICAL IMPLICATIONS: The results of this study point to the possible necessity for the development of novel interventions to improve and enhance communication and collaboration between FCPs and informal caregivers.

The impact of formal and informal support on emotional stress among non-co-resident caregivers of persons with dementia.

OBJECTIVES: The purpose of this study was to examine the prevalence of formal and informal support between non-co-resident and co-resident family caregivers of persons with dementia and to investigate the impact of receiving formal or informal assistance on family caregivers' residential status and their perceived emotional stress. METHOD: We used secondary data from the 2018 National Survey of Older American Act conducted by the Administration for Community Living. We selected 751 primary family caregivers of persons with dementia and conducted regression analyses to explore our research questions. RESULTS: Non-co-resident caregivers of persons with dementia were younger, racially and ethnically diverse, employed, and had higher income than co-resident caregivers. They were less likely to utilize formal support, such as caregiver training or education (p = .005) and respite care (p = .019) but more likely to rely on informal support in their social networks (p = .002), compared to co-resident caregivers. Non-co-resident caregivers who had better informal support systems showed less emotional stress than co-resident caregivers (p = .024). CONCLUSION: Findings from our study suggest the importance of engaging informal networks to alleviate emotional stress of non-co-resident caregivers of persons with dementia. Furthermore, it is critical to help them utilize adequate caregiver training and education as well as respite care before their loved ones experience dramatic functional and health declines.

Use of Home Care Services Reduces Care-Related Strain in Long-Distance Caregivers.

BACKGROUND AND OBJECTIVES: Prior work examining the role of older adult home care service use in alleviating strain in family caregivers has resulted in contradictory findings. However, prior research has been entirely limited to caregivers who live within close geographical proximity to their care recipients. Long-distance caregivers are a unique caregiving subgroup that has remained understudied. Guided by the stress process model, this study examined if the association between primary caregiving stressors (the care recipient's functional and cognitive status) and secondary stressors (perceived role strains related to work and to other family responsibilities) in long-distance caregivers was mediated by the care recipient's utilization of home care services. RESEARCH DESIGN AND METHODS: The sample included 166 long-distance caregivers in the United States who provide and manage care to a community-dwelling care recipient living 2 or more hours away. Participants reported on their care recipient's cognitive and functional status, perceived interference of caregiving with work and other family responsibilities, and the care recipient's use of home care services. RESULTS: Path analyses show that home care use by the care recipient fully mediated the association between care recipients' functional impairment and caregiver strains (work and family). Furthermore, home care use partially mediated the effects of care recipients' cognitive impairment on caregiver strains. DISCUSSION AND IMPLICATIONS: Results indicate that the care recipient's home care service utilization may serve as a protective factor against care-related strain in long-distance caregivers. These findings can be used to inform intervention efforts focused on a family-centered care approach that can be specifically tailored to long-distance caregivers.

The Social Context of Driving Cessation: Understanding the Effects of Cessation on the Life Satisfaction of Older Drivers and Their Social Partners.

Older adults with vision loss and a friend or family member were interviewed over a 2-year period. We examined the effects of driving cessation on life satisfaction among older adults and a social contact. Drivers' use of public transportation was examined as a moderator. Driving cessation was associated with a decline in life satisfaction among social partners but not for the drivers. Drivers' use of public transportation at baseline moderated the effects of cessation on changes in well-being among social partners, but had little effect on the life satisfaction of the drivers. Life satisfaction was greater among the social partners of ex-drivers who used public transportation more frequently. The association between driving cessation and well-being should be studied in the context of older drivers' social networks. Infrastructure (e.g., subways and buses) that supports transportation needs plays an important role in mitigating the effects of cessation on older adults' social networks.

Transportation and Aging: An Updated Research Agenda to Advance Safe Mobility among Older Adults Transitioning From Driving to Non-driving.

Engagement in civic, social, and community life plays an important role in health, well-being, and quality of life, and requires individuals to be mobile in their environment. In this article, we review what is currently known about 2 areas relevant to safe mobility for older drivers and identify future research in these areas. Using a framework for transportation and safe mobility, 2 key areas were selected for review: the process of transitioning to non-driving and the maintenance of mobility after driving has ceased. This article serves as a companion to another article that used the same approach to explore safe mobility issues for older adults who are still driving. We found that although there has been progress in supporting transitioning process to non-driving and improving mobility options for older adults following driving cessation, many knowledge gaps still exist. We identified several research topics that would benefit from continued scientific inquiry. In addition, several themes emerged from the review, including the need for: multidisciplinary, community-wide solutions; large-scale, longitudinal studies; improved education and training for older adults and the variety of stakeholders involved in older adult transportation; and the need for programs and interventions that are flexible and responsive to individual needs and situational differences.

A population study of correlates of social participation in older adults with age-related vision loss.

OBJECTIVE: To examine personal characteristics, disease-related impairment variables, activity limitations, and environmental factors as correlates of social participation in older adults with vision loss guided by the World Health Organization's International Classification of Functioning, Disability and Health Model. DESIGN: Baseline data of a larger longitudinal study. SETTING: Community-based vision rehabilitation agency. SUBJECTS: A total of 364 older adults with significant vision impairment due to age-related macular degeneration. MAIN MEASURES: In-person interviews assessing social participation (i.e. frequency of social support contacts, social/leisure challenges faced due to vision loss, and of social support provided to others) and hypothesized correlates (e.g. visual acuity test, Functional Vision Screening Questionnaire, ratings of attachment to house and neighborhood, environmental modifications in home). RESULTS: Regression analyses showed that indicators of physical, social, and mental functioning (e.g. better visual function, fewer difficulties with instrumental activities of daily living, fewer depressive symptoms) were positively related to social participation indicators (greater social contacts, less challenges in social/leisure domains, and providing more support to others). Environmental factors also emerged as independent correlates of social participation indicators when functional variables were controlled. That is, participants reporting higher attachment to their neighborhood and better income adequacy reported having more social contacts; and those implementing more environmental strategies were more likely to report greater challenges in social and leisure domains. Better income adequacy and living with more people were related to providing more social support to others. CONCLUSION: Environmental variables may play a role in the social participation of older adults with age-related macular degeneration.

Developmental regulation with progressive vision loss: Use of control strategies and affective well-being.

The present study addresses older adults' developmental regulation when faced with progressive and irreversible vision loss. We used the motivational theory of life span development as a conceptual framework and examined changes in older adults' striving for control over everyday goal achievement, and their association with affective well-being, in a sample of 364 older adults diagnosed with age-related macular degeneration. Using longitudinal data from 5 occasions at 6-month intervals, we examined intraindividual change in control strategies, and how it was related to change in affective well-being, in terms of self-rated happiness and depressive symptoms. Mixed model analyses confirmed our hypotheses that (a) intraindividual change, particularly in selective primary control and in compensatory secondary control (CSC), predict change toward higher happiness ratings and lower depression; and (b) as functional abilities (instrumental activities of daily living) declined, CSC became increasingly predictive of better affective well-being. Overall, the findings suggest that CSC strategies are essential for maintaining affective well-being when physical functioning declines. Intensified selective primary control striving may be effective to achieve goals that have become difficult to reach but are not associated with affective well-being, possibly because struggling with difficulties undermines the experience of enjoyable mastery. In contrast, goal adjustments and self-protective thinking may help to find pleasure even from restricted daily activities.

Anxiety and depression in patients with advanced macular degeneration: current perspectives.

Age-related macular degeneration (AMD) - despite advances in prevention and medical treatment options - remains prevalent among older adults, often resulting in functional losses that negatively affect the mental health of older adults. In particular, the prevalence of both anxiety and depression in patients with AMD is high. Along with medical treatment options, low vision rehabilitation and AMD-specific behavioral and self-management programs have been developed and have demonstrated effectiveness in improving the mental health of AMD patients. This article reviews the prevalence of anxiety and depression in patients with advanced AMD, discusses potential mechanisms accounting for the development of depression and anxiety in AMD patients, presents the state-of the-art of available interventions for addressing anxiety and depression in AMD patients, and delineates recommendations for eye care professionals regarding how to screen for these two prevalent mental health problems and how to facilitate appropriate treatment for patients with AMD.

Addressing depression in a long-term care setting: a phase II pilot of problem-solving treatment.

PURPOSE: This was a Phase II pilot study of a problem-solving treatment (PST) to address subsyndromal depression in residents of long-term care facilities. Our goal was to demonstrate PST implementation feasibility and to identify PST's potential for reducing depressive symptoms in this geriatric health care setting. METHODS: Eligible participants were randomized to receive a PST treatment (six 1-hour sessions) or a social contact comparison (6 "friendly" visits) after an initial baseline assessment. Follow-up assessments occurred 7 weeks later (after treatment) and 2 months posttreatment. The basic analytic approach was based on an intention-to-treat analysis. FINDINGS: We enrolled 21 elderly subjects in the PST group and 16 elderly subjects in the social contact comparison group. The PST group experienced a decline in depression scores compared with the social contact group. Although not statistically significant (likely due to the small sample size), PST was associated with decreased depressive symptom scores for those who were able to complete the intervention. Implementation proved to be difficult in terms of study recruitment and intervention acceptance and adherence. IMPLICATIONS: These study findings point to the potential benefits of an integrated mental health component in long-term care, involving rehabilitation professionals who are already working with the older adults in both postacute/short-stay and long-stay settings.

Perceived overprotection, instrumental support and rehabilitation use in elders with vision loss: a longitudinal perspective.

OBJECTIVES: This study's purpose was to investigate changes in perceived overprotection - a problematic aspect of close relationships - over time in relationship to instrumental support receipt and vision rehabilitation service use in a sample of older adults with vision impairment. METHODS: Participants were 584 older adults with chronic vision impairment who were interviewed three times over a 12-month period. Longitudinal data were analysed using a latent growth curve methodology to examine change over time in perceived overprotection and instrumental support in relation to vision rehabilitation service use. MAIN OUTCOME MEASURES: Self-reported levels of overprotection and receipt of instrumental support. Results. Over time perceived overprotection increased but not instrumental support. While perceived overprotection was positively associated with instrumental support initially, over time this relationship did not emerge. Perceived overprotection and instrumental support functioned as predictors of vision rehabilitation hours. However, over time vision rehabilitation service use did not influence these social supports. CONCLUSIONS: Perceived overprotection increases over time, yet this change is unaffected by rehabilitation service use and instrumental support. Both family members and elders need to be involved in the vision rehabilitation process and educated about how some level of independence can be regained.

Change in psychological control in visually impaired older adults over 2 years: role of functional ability and depressed mood.

OBJECTIVES: The life-span theory of control is applied to study change in vision-specific control strategies in visually impaired older individuals, depending on performance in instrumental activities of daily living (IADL) and depressed mood. METHOD: Longitudinal data from visually impaired individuals (at baseline: N = 364; mean age = 82.8 years; visual acuity less than 20/60) measured at three occasions with 1-year intervals in-between were analyzed. A newly established vision-specific control scale to assess selective primary control (SPC), selective secondary control (SSC), compensatory primary control (CPC), and compensatory secondary control (CSC) was used. Linear and nonlinear (quadratic and piecewise) generalized mixed models with gamma response distribution to fit the skewed data were applied. RESULTS: CPC progressively increased as IADL capacity decreased up to a turning point, at which CPC plateaued, whereas all other strategies declined linearly with IADL decrease. Controlling for depressed mood did not change these relationships for CPC, SPC, and SSC but absorbed IADL-related decline of CSC. Higher depression was associated with less SPC, SSC, and CSC, but only slightly with less CPC. DISCUSSION: IADL plays an important role triggering a shift in adaptational strategies from selective control to CPC in visually impaired older adults and possibly other disabled populations.

The Vision-Specific Optimization in Primary and Secondary Control (OPS) Scale.

OBJECTIVE: To successfully address the challenges of age-related visual impairment in rehabilitation and health care settings, it is crucial to gain a better understanding of the psychological and behavioral adaptations that occur in these populations. The purpose of this study was to modify the Optimization in Primary Secondary Control Scale (OPS) (Heckhausen Schulz and Wrosch 1999) to assess the utilization of lifespan control strategies among older adults with visual impairment. METHOD: The Optimization in Primary and Secondary Control Scale (OPS) (Heckhausen et al. 1999) was used to develop a vision-specific version of this measure (i.e., VIS-OPS). The VIS-OPS was administered to older adults with recent vision loss (N = 364; Mean age = 82.9 years). Theory-driven confirmatory factor analysis was used to help refine the instrument and confirm the scale's four-factor structure. RESULTS: Items were removed from three of the four VIS-OPS subscales due to low squared-multiple correlations and poor model fit. Inter-item reliabilities for the resultant subscales ranged from 0.61 to 0.72. The final four-factor model fit the data well (RMSEA = .06, 90% CI .05--.06), with all items loading significantly on their associated factors (i.e. subscales). Correlational analyses provided criterion-related validity for the VIS-OPS with disability and psychosocial functioning measures in the expected directions. CONCLUSIONS: The VIS-OPS will allow researchers to more systematically and precisely measure control strategy use in reference to specific challenges associated with visual impairment, and may serve as a model for examining control strategy use in the context of other disabilities.

Impact of vision impairment on intensity of occupational therapy utilization and outcomes in subacute rehabilitation.

OBJECTIVE: To examine whether vision impairment is a predictor of intensity of occupational therapy utilization and outcomes in a sample of older adults ages ≥55 receiving subacute rehabilitation in a long-term care setting. METHOD: Data for this cohort study were collected by means of structured, in-person interviews with 100 older adult rehabilitation patients at admission to a subacute unit in a long-term care facility and by medical chart review after discharge. RESULTS: Regression analyses indicated that after controlling for sociodemographic, health, and social support variables, worse contrast sensitivity was a significant predictor of decreased time in occupational therapy, and worse visual acuity was a significant predictor of higher functional dependency at discharge. CONCLUSION: Vision impairment may prevent full use of occupational therapy and hinder occupational therapy efficacy in subacute care settings. Study findings underscore the importance of developing low vision rehabilitation interventions that can be delivered in conjunction with more traditional subacute rehabilitation.

Challenges faced by older adults with vision loss: a qualitative study with implications for rehabilitation.

OBJECTIVE: To provide an in-depth assessment of challenges faced by older adults with recent vision loss and to determine changes in the nature of these challenges over time for the purpose of informing the design of vision rehabilitation services. DESIGN: Longitudinal, qualitative study with three time points. SETTING: Vision rehabilitation agency. SUBJECTS: Three hundred and sixty-four older adults aged 65 with significant vision impairment due to age-related macular degeneration. INTERVENTIONS: In-person interviews conducted at baseline, one year and two years and coded using a qualitative analytical approach. MAIN MEASURES: Open-ended questions assessing challenges faced due to vision loss in functional, social and psychological life domains. RESULTS: Almost all participants reported a wide variety of challenges across all three domains with the most variety in the functional domain. Over a two-year period, functional challenges (e.g. using transportation) increased, social challenges (e.g. recognizing people) remained stable, and psychological challenges (e.g. negative affect) decreased overall. CONCLUSIONS: Although functional challenges are predominant, social and psychological challenges are quite common and need to be addressed in vision rehabilitation. Rehabilitation planning should also consider that vision-related challenges can change over time.

The adaptation dynamics of chronic functional impairment: what we can learn from older adults with vision loss.

This study used vision loss due to age-related macular degeneration to learn about adaptation processes related to chronic functional impairment, focusing on Horowitz and Reinhardt's (1998) concept of Adaptation to Age-related Vision Loss (AVL) as the outcome. We hypothesized that impacts of visual acuity on AVL are mediated by perceived functional vision losses and functional abilities, and tested for "adaptive" weakening of this impact with ongoing loss. Longitudinal data covering a one-year interval from samples with age-related macular degeneration gathered in New York (N = 361) and Heidelberg (Germany, N = 90) were used. We analyzed the hypothesized causal structure by modeling latent change scores, and checked if those with low, medium, and high levels of vision loss at baseline differ in the relations between one-year change scores. Results confirmed that impacts of vision loss on AVL are mediated by decline in functional ability. However, under the most severe levels of vision loss at baseline, functional decline showed only a minor impact on AVL change not explained by a lack of further decline in vision. Findings confirm the effectiveness of adaptation in terms of reduced reactivity to functional losses across increasing level of chronic impairment. Thus, adaptation, weakening the impact of chronic functional impairment on psychological outcomes over time with disease progression, deserves consideration in the study of psychological consequences of chronic physical health conditions in old age.

Tackling vision-related disability in old age: an application of the life-span theory of control to narrative data.

This study used the life-span theory of control (Heckhausen, J., & Schulz, R.) to examine adaptation to disability in old age. A narrative approach to data collection was used to assess the strategies employed by 364 older adults with macular degeneration to deal with daily challenges. Findings revealed a rich array of strategies. Compensatory Primary Control was reported by nearly all respondents, Compensatory Secondary Control by a majority, and Selective Primary Control by half of the participants. Selective Secondary Control was the least reported. Differences in strategy use depending on level of vision impairment were the most pronounced within the category of Compensatory Primary Control for strategies that involved using help from others and alternative means. Within the category of Selective Secondary Control, effort to maintain a positive outlook was associated with higher impairment levels, whereas within the category of Compensatory Secondary Control, attempts not to dwell on problems related to vision were associated with lower impairment levels. Implications for conceptual development and future research are discussed.