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Outcomes Among Family Caregivers of Aphasic Versus Nonaphasic Stroke Survivors
Adverse consequences are known to occur in family members responsible for providing care to stroke survivors. However, the differential effect of aphasic versus nonaphasic stroke on caregivers has not been well studied. This study compares selected outcomes (e.g., perceived task difficulty, depressive symptoms, and other negative stroke-related outcomes) among caregivers of aphasic (n = 46) and nonaphasic (n = 113) stroke survivors. Results indicated that caregivers of aphasic survivors perceived greater difficulty with tasks and had more negative stroke-related outcomes than caregivers of nonaphasic survivors. Communication with the survivor was rated as most upsetting and difficult by caregivers in the aphasic group, followed by managing behaviors. Lack of time for family and friends was evident. Female caregivers and caregivers of survivors with self-care deficits also perceived greater difficulty with tasks and negative outcomes. Comprehensive assessment of the unique needs of caregivers of aphasic survivors is suggested for more individualized nursing interventions.
More than two thirds of the nation’s 4.6 million stroke survivors require the daily assistance of a family caregiver (American Heart Association, 2003; Dewey et al., 2002; Dorsey & Vaca, 1998). Caregivers help their loved ones deal with multiple motor, sensory, visual, language, cognitive, and affective impairments inflicted by stroke, with depression being particularly common (Kelly-Hayes et al., 1998).
Research has documented the needs and concerns of stroke caregivers (Bakas, Austin, Okonkwo, Lewis, & Chadwick, 2002), task difficulties (Bakas, Austin, Jessup, Williams, & Oberst, 2004; Bakas & Burgener, 2002; Hartke & King, 2002), high prevalence of caregiver depression (34%–54%; Anderson, Linto, & Stewart-Wynne, 1995; Han & Haley, 1999), social complications (Bakas & Champion, 1999; Hartke & King, 2002), and even deterioration of physical health and increased risk of mortality as a result of providing care (Bakas & Champion, 1999; Schulz & Beach, 1999; Silliman, Fletcher, Earp, & Wagner, 1986; Williams, 1993). Little research, however, has focused specifically on caregivers who provide care for aphasic stroke survivors (Han & Haley, 1999). Aphasia greatly affects communication between stroke survivors and their caregivers (Booth & Swabey, 1999; Kagan et al., 2004), making caregiver tasks more difficult, especially those focused on managing difficult behaviors and providing emotional support. Social isolation and other negative caregiver quality of life (QOL) outcomes are also likely to occur. The one study exploring differences in outcomes between caregivers of aphasic and nonaphasic stroke survivors (McClenahan & Weinman, 1998) found no differences in general health perceptions, dispositional optimism, perceived social support, coping, generalized self-efficacy, or illness perception, although the measures were rather global. No reported study has explored differences in stroke-specific caregiver outcomes in this context.
This article compares differences in perceived task difficulty, depressive symptoms, and other stroke-related outcomes between family caregivers of aphasic and nonaphasic survivors at 1 and 4 months after stroke. Stroke-related outcomes were defined as perceived changes in social functioning, subjective well-being, and physical health as a result of providing care (Bakas & Champion, 1999). A secondary purpose was to identify caregiver tasks perceived as difficult, upsetting survivor communication and behavior problems, and worst stroke-related caregiver outcomes in the aphasic group.
Participants and Data Collection
A convenience sample of 159 family caregivers of aphasic (n = 46) and nonaphasic (n = 113) stroke survivors was recruited from hospitals and clinics after approval from university and hospital institutional review boards. Following informed consent, questionnaires about survivor impairments, perceived task difficulties, depressive symptoms, and other stroke-related caregiver outcomes were administered at 1 and 4 months after stroke. One and 4 months were chosen in order to provide caregivers with the opportunity to provide care. Data collection occurred in the clinical setting or by telephone. Attrition rate between 1 and 4 months was 6.3%.
Caregivers of aphasic survivors also completed questionnaires about upsetting survivor communication and behavior problems. Assignment of caregivers to the aphasic versus nonaphasic groups was based on chart evidence of aphasia (any type noted in the progress notes by physicians, neuropsychologists, or speech therapists) or by caregiver report of aphasia symptoms. Eligibility criteria included being an unpaid family caregiver or significant other of a noninstitutionalized stroke survivor within 1 month after stroke who could read and speak English and who provided at least two different types of caregiver tasks from the Oberst Caregiving Burden Scale (OCBS; Bakas et al., 2004; Carey, Oberst, McCubbin, & Hughes, 1991).
The 5-item language subscale from the Stroke Specific Quality of Life Scale Proxy Version (SSQOL Proxy; Williams, Redmon, Martinez, & Weinberger, 2000; Williams, Weinberger, Harris, Clark, & Biller, 1999) was used to measure communication problems in stroke survivors as rated by their caregivers, with lower scores indicating more impairment. The 6-item mobility subscale and the 5-item self-care subscale were also used. Items are rated on a 5-point scale ranging from couldn’t do it at all to no trouble at all (Williams et al., 1999). Since proxy measures completed by caregivers tend to yield only slightly higher disability scores than disability measures completed by patients (Knapp & Hewison, 1999; Williams et al., 2000), the SSQOL Proxy was chosen as a general indicator of communication, mobility, and self-care impairment. Both the SSQOL and the SSQOL Proxy have good evidence of internal consistency reliability, construct validity, and responsiveness to change for all 12 subscales (Williams et al., 1999; Williams et al., 2000). Cronbach alpha for the SSQOL Proxy subscales used in this study (language, mobility, self-care) ranged between 0.87 and 0.94.
The 15-item difficulty subscale from the OCBS (Bakas et al., 2004; Carey et al., 1991) was used to measure caregiver perceptions of task difficulty. Items are rated on a 5-point scale ranging from not difficult to extremely difficult (Bakas et al., 2004). Evidence of internal consistency reliability, unidimensionality, and content and construct validity for the OCBS has been previously reported (Bakas et al., 2004; Bakas & Burgener, 2002; Bakas & Champion, 1999; Carey et al., 1991; Oberst, 1990). Cronbach alphas for this study at 1 and 4 months were 0.89 and 0.90, respectively.
Depressive symptoms experienced by caregivers were assessed by the 9-item Patient Health Questionnaire Depression Scale (PHQ-9), which has satisfactory evidence of internal consistency reliability, validity, specificity, and sensitivity (Kroenke, Spitzer, & Williams, 2001; Spitzer, Kroenke, & Williams, 1999; Spitzer, Williams, Kroenke, Hornyak, & McMurray, 2000). The PHQ-9 items are the nine DSM-IV depressive disorders criteria rated on a 4-point scale ranging from not at all to nearly every day (Kroenke et al., 2001). Cronbach alphas for the PHQ-9 in this study at 1 and 4 months were 0.80 and 0.86 respectively.
Stroke-related caregiver outcomes were measured by the 15-item Bakas Caregiving Outcomes Scale (BCOS; Bakas & Champion, 1999). Items address perceived changes in social functioning, subjective well-being, and physical health specifically as a result of providing care and are rated on a 7-point scale ranging from changed for the worst to changed for the best (Bakas & Champion). Satisfactory internal consistency reliability and content, criterion-related, and construct validity have been reported (Bakas & Champion). Cronbach alphas for the present sample at 1 and 4 months were 0.85 and 0.90, respectively.
Only caregivers in the aphasic group completed the 24-item Revised Memory and Behavior Problems Checklist Upset Subscale (MBPC), which measures caregiver reaction to problematic behaviors in dementia (Teri et al., 1992). An additional 25 stroke-specific behavior items were added based on a review of the literature (Bakas et al., 2002; Williams, 1994; Williams & Dahl, 2002), as well as three items measuring upsetting survivor communication problems (trouble speaking, trouble understanding, and trouble keeping up with conversation). The MBPC with additional items was analyzed at the item level because psychometric properties have not yet been determined in stroke caregivers at the summative scale level.
Descriptive statistics were used to summarize caregiver and stroke survivor characteristics and measures. Longitudinal data were analyzed using two-way repeated measures analysis of variance (ANOVA) for each dependent variable. Dependent variables were survivor communication as well as caregiver task difficulty, depressive symptoms, and stroke-related outcomes. Independent variables were time (1 versus 4 months after stroke) and group (aphasic versus nonaphasic). Post-hoc paired t tests measured within-group differences over time, and independent samples t tests measured between group differences at 1 and 4 months. With four post-hoc comparisons for each dependent variable, a more stringent alpha of p < .0125 was used based on the Bonferroni correction for multiple comparisons (Munro, 2001). Assumptions for compound symmetry and equality of variance- covariance matrices were tested (Munro) and corrected for if necessary. Although a few measures were skewed, there were no changes in the results when these scales were transformed using recommended procedures (Tabachnick & Fidell, 1996). SSQOL Proxy ratings for mobility and self-care at 1 month were added as covariates, and caregiver gender was added as another independent variable using repeated measures analysis of covariance (ANCOVA). Item frequency distributions from the OCBS, the MBPC (with added items), and the BCOS were inspected to determine difficult caregiver tasks, upsetting survivor communication and behavior problems, and the worst caregiver outcomes in the aphasic group.
Caregiver and Stroke Survivor Characteristics
Most caregivers were female and either spouses or adult children (Table 1). The proportion of female caregivers was larger in the aphasic group than in the nonaphasic group (Chi Square = 6.20, p < .05). Using the total sample, female caregivers had significantly more difficulty with tasks (t = –3.23; –4.12, p < .01), more depressive symptoms (t = –3.43; –4.70, p < .001), and more negative stroke-related outcomes (t = 2.88; 2.81, p <.01) than male caregivers at both 1 and 4 months after stroke. Caregivers of aphasic survivors rated survivor mobility (t = –3.86, p < .001) and self-care (t = –4.86, p < .001) as being significantly more severe than caregivers of nonaphasic survivors using the 1-month SSQOL Proxy. Therefore, these variables were entered as covariates in subsequent analyses using ANCOVA, with caregiver gender added as an additional independent variable. The remaining demographic characteristics for caregivers and stroke survivors were similar for both groups (Table 1).
With both groups combined, caregivers rated survivors’ communication impairments as mild, on average, at both 1 and 4 months (Table 2). As expected, two-way repeated measures ANOVA revealed relatively more severe communication problems for the aphasic group, F(1,146) = 96.12, p < .001, although the ratings did improve significantly over time, F(1,146) = 13.19, p < .001. There were no significant time-by-group interaction effects. Post-hoc independent samples t tests were significant, indicating that communication problems were more severe for the aphasic group at both 1 and 4 months after stroke (t = –7.52; –7.40, p < .001). Paired t tests of within-group changes over time were significant for the aphasic group (t = –2.67, p < .01), but not for the nonaphasic group using the Bonferroni corrected alpha of p < .0125. Subsequent ANCOVA revealed significant main effects for group, F(1,141) = 51.5, p < .001; caregiver gender, F(1,141) = 10.93, p < .01; survivor self-care, F(1,141) = 7.46, p < .01; and time, F(1,141) = 6.16, p < .05; but not for survivor mobility. Only the time by self-care interaction was significant, F(1,141) = 4.29, p < .05. In other words, the ANCOVA revealed that survivor communication was rated more severe by caregivers in the aphasic group, female caregivers, and by caregivers of survivors with more self-care deficits, although communication did improve over time. More severe survivor communication problems were significantly related to increased caregiver task difficulty (r = –.38, –.29, p < .001), caregiver depressive symptoms (r = –.18, –.20, p <.05), as well as more negative stroke-related caregiver outcomes (r = .23, .31, p < .01) at both 1 and 4 months after stroke.
Caregiver Task Difficulty
With both groups combined, the OCBS scores were fairly low, indicating that tasks were perceived as only slightly to moderately difficult overall (Table 2). Two-way repeated measures ANOVA revealed that caregivers in the aphasic group experienced relatively more difficulty with tasks, F(1,144) = 16.89, p < .001. Across both groups, tasks also became less difficult between 1 and 4 months after stroke, F(1,144) = 5.14, p < .05, and there were no significant interaction effects. Post-hoc t tests showed greater task difficulty for the aphasic group at both 1 and 4 months after stroke. Paired t tests of within-group changes between 1 and 4 months failed to reach significance for either group based on the corrected alpha of p <.0125 (Figure 1). Subsequent ANCOVA revealed significant main effects for survivor self-care, F(1,139) = 23.26, p < .001; and caregiver gender, F(1,139) = 8.85, p < .01; but not for group, time, or survivor mobility. There were no significant interactions. In other words, the ANOVA revealed that caregivers in the aphasic group experienced relatively more difficulty with tasks. The ANCOVA revealed that female caregivers and those caring for survivors with self-care deficits also experienced more difficulty with tasks.
Difficult Tasks and Problematic Behaviors
Because tasks were significantly more difficult for the aphasic group at both 1 and 4 months in the initial ANOVA, item distributions from the OCBS and the MBPC (with added items) in this group were inspected to determine which caregiver tasks and survivor communication and behavior problems were perceived as most problematic (Table 3). Only items rated moderately, very, or extremely difficult or upsetting are listed in Table 3. Communication with the stroke survivor was difficult for approximately half of the caregivers, followed by managing difficult behaviors and finances and talking with health professionals. The survivors’ trouble speaking was upsetting for about half of the caregivers. Sad or depressed survivor behaviors were rated as upsetting by close to 40% of caregivers at both 1 and 4 months after stroke. Additional difficult tasks and upsetting survivor behaviors are detailed in Table 3.
Caregiver Depressive Symptoms
The overall PHQ-9 means were relatively low at both 1 and 4 months (Table 2), although 18.1% of the caregivers scored in the moderately depressed range (PHQ-9 score > 10; Kroenke et al., 2001). An additional 18.1%, although scoring in the nondepressed range, were currently taking antidepressant medications, suggesting that as many as 36% of the caregivers suffered from depression. There were no significant main or time-by-group effects. Despite these findings, post-hoc paired t tests for the nonaphasic group showed a significant improvement in depressive symptoms over time, whereas the aphasic group remained unchanged (Figure 2). Subsequent ANCOVA revealed significant main effects for survivor gender, F(1,142) = 11.93, p < .01; and survivor self-care, F(1,142) = 5.34, p < .05; but not for group, time, or survivor mobility. There were no significant interactions. In other words, the ANCOVA revealed that female caregivers and caregivers of survivors with more self-care deficits experienced relatively more depressive symptoms. Depressive symptoms, however, were similar for caregivers of aphasic and nonaphasic survivors.
Stroke-Related Caregiver Outcomes
The BCOS means for the combined groups at both 1 and 4 months (57.2 and 58.4, respectively) were less than the scale midpoint of 60 for possible scores, indicating that caregiver lives on average had changed for the worst (Table 2). Although there were no significant changes in outcomes from 1 to 4 months after stroke, caregivers in the aphasic group experienced relatively more negative outcomes, F(1,147) = 4.17, p < .05. A post-hoc t test indicated that this difference was significant at 1 month after stroke, but not at 4 months, based on the corrected alpha of p < .0125 (Figure 3). Subsequent ANCOVA revealed significant main effects for survivor gender, F(1,142) = 8.84, p < .01; and survivor self-care, F(1,142) = 6.38, p < .05; but not for group, time, or survivor mobility. Time by self-care, F(1,142) = 7.19, p < .01; and time by mobility, F(1,142) = 5.74, p < .05, interactions were significant. In other words, the ANOVA revealed that caregivers in the aphasic group experienced relatively more negative caregiver outcomes. The ANCOVA revealed that female caregivers and caregivers of survivors with self-care deficits also experienced relatively more negative caregiver outcomes.
Because overall stroke-related caregiver outcomes were significantly worse for the aphasic group in the initial ANOVA, item distributions from the BCOS were inspected to determine which aspects of caregiver lives had deteriorated most. Time for family and social activities had deteriorated for most (55%–85%) caregivers in the aphasic group at both time points. Negative changes in level of energy, financial well-being, emotional well-being, and roles in life were found in approximately half of the caregivers. Roughly 24% at 1 month and 21% at 4 months indicated their physical health had worsened from providing care. Additional negative changes in caregiver lives are detailed in Table 3.
This study found that survivor communication was rated more severely for the caregiver in the aphasic group, even when adding covariates in subsequent analyses. Survivor communication problems were also associated with more task difficulty, caregiver depressive symptoms, and negative stroke-related caregiver outcomes. These findings support the challenges that caregivers must face in communicating with aphasic survivors (Booth & Swabey, 1999; Kagan et al., 2004). In fact, the survivors’ trouble with speaking was upsetting for a larger proportion of caregivers in the aphasic group than any of the other problem behaviors or caregiver tasks. Past studies have found that managing problem behaviors and providing emotional support are among the most difficult tasks for stroke caregivers (Anderson et al., 1995; Bakas et al., 2002; Bakas et al., 2004; Williams, 1994). Without exploring the effect of aphasic versus nonaphasic stroke on caregivers, the unique difficulties related to communicating with aphasic survivors would not be fully appreciated.
This study also found that caregivers of aphasic survivors experienced more difficulty with tasks than caregivers of nonaphasic survivors, although caregiver gender and survivor self-care prevailed in subsequent analyses. These findings suggest that female caregivers and those caring for survivors with self-care deficits were also likely to perceive tasks as being difficult. Again, the most difficult tasks for caregivers of aphasic survivors were communicating with the survivor, managing difficult behaviors such as sadness or depression, dealing with finances, and talking with health care professionals. Comprehensive assessment and individualized interventions are needed, particularly because mobility and self-care impairments were significantly more severe in the aphasic group. Better communication with healthcare professionals is also needed (Bakas et al., 2002). The OCBS (Bakas et al., 2004; Carey et al., 1991) or the Caregiver Needs and Concerns Checklist (CNCC; Bakas et al., 2002) could be used to help nurses identify particular areas where caregivers might require assistance.
The severity of caregiver depressive symptoms was very similar for both the aphasic and nonaphasic groups, although communication problems as measured by the SSQOL Proxy were mildly related to caregiver depressive symptoms (p < .05). Depression can be attributed to many causes outside of the caregiving situation, which may have overshadowed the effect of aphasia, but a substantial proportion of caregivers were experiencing moderate depression and would have benefited from antidepressant therapy or counseling. This is particularly important because caregiver stress is a leading cause of costly long-term institutionalization of stroke survivors (Han & Haley, 1999). Female caregivers and those dealing with survivor self-care deficits were especially prone to depressive symptoms in this study. The PHQ-9 (Kroenke et al., 2001) is a brief instrument that could be used to screen caregivers for depressive symptoms in practice settings.
Caregivers of aphasic survivors had more negative stroke-related outcomes; however, these findings were no longer significant in subsequent analyses. Caregiver gender and survivor self-care were more strongly associated with caregiver outcomes than the presence of aphasia. Nevertheless, substantial proportions of caregivers in the aphasic group experienced negative stroke-related caregiver outcomes. Similar to the findings of other studies (Bakas & Champion, 1999; Hartke & King, 2002; Schulz & Beach, 1999; Silliman et al., 1986; Williams, 1993), well over half of the caregivers in the aphasic group reported a lack of time for social activities with family and friends, and almost a quarter indicated that their physical health had deteriorated as a result of providing care. To protect QOL for stroke caregivers, nursing assessment of stroke-related outcomes is an essential prerequisite to intervention. One brief scale to quickly assess these factors is the BCOS (Bakas & Champion, 1999).
This study has several limitations. The SSQOL Proxy language ratings of communication impairment supported the assignment of caregivers to aphasic versus nonaphasic groups. Because the specific types of aphasia exhibited by the stroke survivors were not assessed, some types of aphasia may not have been well represented. Male caregivers were underrepresented in the aphasic group, limiting generalizability of the findings to primarily female caregivers. Exploring group-by-group gender interactions was also not possible. Other than African Americans, minorities were underrepresented as well.
Also noteworthy is the mean age of survivors (M = 62.5 years, range 27–89) and caregivers (M = 51.7 years, range 21–78). Findings may not fully represent survivors and caregivers 65 years and older. Approximately one-third of the caregivers in the study were adult children, and another 15% were relatives other than spouses. This lowered the mean age for caregivers. A little under half of the caregivers were employed either full or part time showing that many had competing demands for their time. This was especially the case with the adult child caregivers.
Last, many of the findings were not significant after subsequent analyses, possibly because of the modest size of the sample, but also because caregiver gender and survivor self-care might be more important than the presence of aphasia in this context. This supports the need for individualized assessment and interventions rather than providing generic one-size-fits-all interventions for family caregivers. Nurses are in an ideal position to assess, intervene, or refer caregivers to other professionals for specific needs they have, particularly because nurses interact with families during rehabilitation.
This study revealed that family caregivers of aphasic survivors experienced relatively poorer communication with the survivor, perceived more difficulty with tasks, and had more negative stroke-related caregiver outcomes than family caregivers of nonaphasic survivors. These findings were also more evident in female caregivers and caregivers of survivors with self-care deficits. Tasks that were particularly difficult or upsetting for caregivers in the aphasic group were communicating with the survivor, managing survivor behaviors, such as sadness or depression, managing finances, and talking with healthcare professionals about the survivor’s condition. Deterioration of family and social activities, lack of energy, and poor emotional and financial well- being were also common. Almost a quarter of caregivers in the aphasic group reported that their physical health had changed for the worse.
The wide array of caregiver difficulties and negative outcomes makes it challenging for rehabilitation nurses to intervene and support caregivers. Detailed assessment of family caregiver needs, difficulties, and outcomes are suggested as a way of selecting individualized nursing interventions or referrals to appropriate resources. The 32-item CNCC (Bakas et al., 2002), 15-item OCBS (Bakas et al., 2004), 15-item BCOS (Bakas & Champion, 1999), or the 9-item PHQ-9 (Kroenke et al., 2001) are examples of tools that could be used in practice settings to identify specific areas where individual caregivers need help. Once problem areas for caregivers have been identified, rehabilitation nurses in both inpatient and outpatient settings can then focus their efforts on specific individualized interventions or referrals for family caregivers of stroke survivors.
This study provides important preliminary data comparing caregivers of aphasic with nonaphasic stroke survivors regarding tasks they perceive as difficult, depressive symptoms, and stroke-related outcomes. Further study is recommended using larger, more representative samples to explore differences between caregivers of aphasic and nonaphasic stroke survivors matched in terms of caregiver gender and survivor self-care. Studies should also be conducted that test multicomponent interventions based on detailed assessments of individual caregiver needs. Individualized multicomponent interventions that are feasible in practice settings are greatly needed. Meanwhile, nurses should consider comprehensive assessment of the unique needs of caregivers of aphasic stroke survivors in order to select more individualized nursing interventions and referrals for this vulnerable population.
Funding for this study was provided by the Center for Enhancing Quality of Life in Chronic Illness, National Institute for Nursing Research, NIH #P30 NR05035 (Center PI: Joan K. Austin, Pilot PI: Tamilyn Bakas), and the National Institute for Neurological Disorders and Stroke, NIH #R01 NS39571-01 (PI: Linda S. Williams). Joan K. Austin, DNS RN FAAN, and Carol J. Farran, DNSc RN FAAN, are acknowledged for their consultation and mentoring. Phyllis Dexter, PhD RN, is acknowledged for her editorial assistance. Approvals for the protection of human subjects used in this manuscript have been obtained from IUPUI and Clarian/Methodist Hospital Institutional Review Boards filed under study numbers 0106-11B and 9903-06, and from Community Hospitals Indianapolis, Community Medical Research Institute Institutional Review Board filed under study number 0106-11B/Bakas.
About the Authors
Tamilyn Bakas, DNS RN FAHA, is an associate professor in the Indiana University School of Nursing, Indianapolis, IN.
Kurt Kroenke, MD, is a senior scientist at Regenstrief Institute and Department of Medicine, Indiana University School of Medicine, Indianapolis, IN.
Laurie D. Plue, MA, is an assistant implementation research coordinator for VA Stroke QUERI in the Roudebush Veterans Administration Medical Center, IN.
Susan M. Perkins, PhD, is an associate professor in the division of biostatistics at the Indiana University School of Medicine, Indianapolis, IN.
Linda S. Williams, MD FAHA, is chief of neurology in the Roudebush Veterans Administration Medical Center, and associate professor in the Indiana University School of Medicine, Indianapolis, IN.
Direct correspondence to Tamilyn Bakas, DNS RN FAHA, Associate Professor, Indiana University School of Nursing, 1111 Middle Drive, NU 417, Indianapolis, IN 46202-5107, or to firstname.lastname@example.org.
American Heart Association. (2003). 2004 Heart and Stroke Statistical Update. Dallas: Author.
Anderson, C. S., Linto, J., & Stewart-Wynne, E. G. (1995). A population-based assessment of the impact and burden of caregiving for long-term stroke survivors. Stroke, 26(5), 843–849.
Bakas, T., Austin, J. K., Jessup, S. L., Williams, L. S., & Oberst, M. T. (2004). Time and difficulty of tasks provided by family caregivers of stroke survivors. Journal of Neuroscience Nursing, 36(2), 95–106.
Bakas, T., Austin, J. K., Okonkwo, K. F., Lewis, R. R., & Chadwick, L. (2002). Needs, concerns, strategies, and advice of stroke caregivers the first 6 months after discharge. Journal of Neuroscience Nursing, 34(5), 242–251.
Bakas, T., & Burgener, S. C. (2002). Predictors of emotional distress, general health, and caregiving outcomes in family caregivers of stroke survivors. Topics in Stroke Rehabilitation, 9(1), 34–45.
Bakas, T., & Champion, V. (1999). Development and psychometric testing of the Bakas Caregiving Outcomes Scale. Nursing Research, 48(5), 250–259.
Booth, S., & Swabey, D. (1999). Group training in communication skills for carers of adults with aphasia. International Journal of Language and Communication Disorders, 34(3), 291–309.
Carey, P. J., Oberst, M. T., McCubbin, M. A., & Hughes, S. H. (1991). Appraisal and caregiving burden in family members caring for patients receiving chemotherapy. Oncology Nursing Forum, 18(8), 1341–1348.
Dewey, H. M., Thrift, A. G., Mihalopoulos, C., Carter, R., Macdonell, R. A., McNeil, J. J., et al. (2002). Informal care for stroke survivors: Results from the North East Melbourne Stroke Incidence Study (NEMESIS). Stroke, 33(4), 1028–1033.
Dorsey, M. K., & Vaca, K. J. (1998). The stroke patient and assessment of caregiver needs. Journal of Vascular Nursing, 16(3), 62–67.
Han, B., & Haley, W. E. (1999). Family caregiving for patients with stroke. Review and analysis. Stroke, 30(7), 1478–1485.
Hartke, R. J., & King, R. B. (2002). Analysis of problem types and difficulty among older stroke caregivers. Topics in Stroke Rehabilitation, 9(1), 16–33.
Kagan, A., Winckel, J., Black, S., Duchan, J. F., Simmons-Mackie, N., & Square, P. (2004). A set of observational measures for rating support and participation in conversation between adults with aphasia and their conversation partners. Topics in Stroke Rehabilitation, 11(1), 67–83.
Kelly-Hayes, M., Robertson, J. T., Broderick, J. P., Duncan, P. W., Hershey, L. A., Roth, E. J., et al. (1998). The American Heart Association Stroke Outcome Classification. Stroke, 29(6), 1274–1280.
Knapp, P., & Hewison, J. (1999). Disagreement in patient and care assessment of functional abilities after stroke. Stroke, 30(5), 934–938.
Kroenke, K., Spitzer, R. L., & Williams, J. B. (2001). The PHQ-9: Validity of a brief depression severity measure. Journal of General Internal Medicine, 16(9), 606–613.
McClenahan, R., & Weinman, J. (1998). Determinants of carer distress in non-acute stroke. International Journal of Language and Communication Disorders, 33(Suppl.), 138–143.
Munro, B. H. (2001). Statistical Methods for Health Care Research (4th ed.). Philadelphia: Lippencott.
Oberst, M. T. (1990). Unpublished data.
Schulz, R., & Beach, S. R. (1999). Caregiving as a risk factor for mortality: The Caregiver Health Effects Study. Journal of the American Medical Association, 282(23), 2215–2219.
Silliman, R. A., Fletcher, R. H., Earp, J. L., & Wagner, E. H. (1986). Families of elderly stroke patients. Effects of home care. Journal of American Geriatrics Society, 34(9), 643–648.
Spitzer, R. L., Kroenke, K., & Williams, J. B. (1999). Validation and utility of a self-report version of PRIME-MD: The PHQ primary care study. Primary Care Evaluation of Mental Disorders. Patient Health Questionnaire. Journal of the American Medical Association, 282(18), 1737–1744.
Spitzer, R. L., Williams, J. B., Kroenke, K., Hornyak, R., & McMurray, J. (2000). Validity and utility of the PRIME-MD patient health questionnaire in assessment of 3000 obstetric-gynecologic patients: The PRIME-MD Patient Health Questionnaire Obstetrics-Gynecology Study. American Journal of Obstetrics and Gynecology, 183(3), 759–769.
Tabachnick, B. G., & Fidell, L. S. (1996). Using Multivariate Statistics (3rd ed.). New York: HarperCollins.
Teri, L., Truax, P., Logsdon, R., Uomoto, J., Zarit, S., & Vitaliano, P. P. (1992). Assessment of behavioral problems in dementia: The revised memory and behavior problems checklist. Psychology and Aging, 7(4), 622–631.
Williams, A. (1994). What bothers caregivers of stroke victims? Journal of Neuroscience Nursing, 26(3), 155–161.
Williams, A. M. (1993). Caregivers of persons with stroke: Their physical and emotional wellbeing. Quality of Life Research, 2(3), 213–220.
Williams, A. M., & Dahl, C. W. (2002). Patient and caregiver perceptions of stroke survivor behavior: A comparison. Rehabilitation Nursing, 27, 19–24.
Williams, L. S., Redmon, G., Martinez, B., & Weinberger, M. (2000). Proxy ratings of Stroke-Specific Quality of Life (SS-QOL) scores. Oral abstracts of the 25th International Stroke Conference. Stroke, 31, 301.
Williams, L. S., Weinberger, M., Harris, L. E., Clark, D. O., & Biller, J. (1999). Development of a stroke-specific quality of life scale. Stroke, 30(7), 1362–1369.