Patient Education and Counseling 34 (1998) 43–51
Psychological distress of caregivers: the mediator effect of caregiving appraisal A.M. Pot*, D.J.H. Deeg, R. van Dyck, C. Jonker Department of Psychiatry and Department of General Practice, Nursing Home Medicine and Social Medicine, Vrije Universiteit, Amsterdam, The Netherlands Received 20 October 1997; received in revised form 20 February 1998; accepted 26 February 1998
Abstract This study concerns the role of caregiving appraisal, whether it explains why stressors in the caregiving situation affect caregivers’ psychological distress. This putative mediator effect of caregiving appraisal is separately tested for spouse and non-spouse caregivers of demented elderly persons. Caregiving appraisal is operationalized by a measure of pressure from informal care as perceived by the caregiver. For spouse caregivers, perceived pressure explained the association between their caregiving tasks and psychological distress. However, the strong association found between behavioral problems and psychological distress was not explained by perceived pressure in spouse caregivers. Furthermore, results showed clear mediator effects of perceived pressure for associations between stressors (both behavioral problems of the demented elder and caregiving tasks) and non-spouse caregivers’ psychological distress. Thus, it is inadequate to focus interventions merely on stressors in the caregiving situation, for non-spouse caregivers in particular. A reduction of perceived pressure from informal care is also needed. 1998 Elsevier Science Ireland Ltd. Keywords: Caregivers; Dementia; Stress; Appraisal; Mediator
1. Introduction The negative consequences of providing care to a demented elderly relative are thoroughly investigated [1]. Several studies have shown that informal caregivers for demented elderly people have higher levels of general psychological distress or (syndromal) depression in comparison with the general population or noncaregiving controls [2–11]. Further*Corresponding author. Tel.: 1 31 20 4448237; fax: 1 31 20 4448231; e-mail:
[email protected]
more, several studies showed associations between stressful aspects of the caregiving situation, such as dementia patients’ behavioral problems or the amount of care provided by caregivers, and caregivers’ psychological well-being [12–15]. This study focuses on whether stressors in the caregiving situation affect caregivers’ psychological well-being as a result of their appraisal of these stressors. In other words, the mediator effect of caregiving appraisal is tested (see Fig. 1). Appraisal of stressful aspects of the caregiving situation has received much attention in the caregiv-
0738-3991 / 98 / $19.00 1998 Elsevier Science Ireland Ltd. All rights reserved. PII S0738-3991( 98 )00048-2
44
A.M. Pot et al. / Patient Education and Counseling 34 (1998) 43 – 51
Fig. 1. Mediator effect of caregiving appraisal.
ing literature. A widely used theoretical model is derived from Lazarus and Folkman’s general stress theory which considers appraisal as a cognitive mediational process [16]. In essence, the primary function of appraisal is to integrate environmental realities and personal interests as effectively as possible. If either one dominates at the expense of the other, psychopathology is likely to occur [17]. Several instruments were developed that measure aspects of caregivers’ appraisal such as the stressfulness of care-recipients’ impairment or the degree to which individual behaviors bother or upset the caregiver [18–24]. These instruments refer in particular to what Lazarus calls primary appraisal. ‘Primary appraisal concerns whether something of relevance to the person’s well-being has occurred’ [17]. Lawton and colleagues aimed at developing an instrument for measuring secondary caregiving appraisal, which they defined as cognitive and affective responses to the demands of caregiving and one’s own behavior in relation to those demands [25]. They included items which asked caregivers to directly relate their (mental) health to stressors in the caregiving situation, thereby confusing assumed stressors and their effects. Using such an instrument, no clear understanding can be obtained of the origins of psychological distress of caregivers and of a possible way to control this distress [26]. Although appraisal is considered as a mediational process, most studies focused on the main instead of the mediator effects of caregiving appraisal, e.g. [27,28]. Some support was found for the mediator effect of caregiving appraisal [19,29]. Lawton et al. found a mediator effect for the relationship between help provided by the caregiver and caregiver’s depression, for both spouse caregivers and adultoffspring caregivers [29]. Furthermore, caregivers’ appraisal mediated the relationship between carerecipients’ behavioral problems and caregivers’ depression for spouse caregivers, but not for adultoffspring caregivers [29]. Haley et al. found some support for the mediator effect of subjective stressfulness on the relationship between caregiving stres-
sors and caregivers’ depression but not on the relationship between caregiving stressors and caregivers’ satisfaction with life [19]. No support was found for the mediator effect of self-efficacy appraisals on the relationship of caregiving stressors and both indicators of caregivers’ well-being. Empirical evidence on the mediator effect of caregiving appraisal is relevant for understanding why specific stressors have a negative effect on caregivers’ psychological functioning. Caregiving appraisal may offer some prospects for intervention beyond stressors of the caregiving situation, because most of these stressors, such as care-recipients’ behavioral problems, can be changed only to a limited degree. Differentiation between spouse and non-spouse caregivers may be necessary in research on mediator effects, because both groups may appraise stressors in the caregiving situation differently, not only quantitively but also qualitatively, due to their different commitment to the demented elder and their different living situations. Whereas caregiving spouses live with their demented spouses, most nonspouse caregivers do not share a household with their demented care-recipients. Therefore, in this study the mediator effect of caregiving appraisal is separately tested for spouse and non-spouse caregivers. Our instrument for measuring caregiving appraisal focuses on an important outcome of the caregivers’ cognitive mediative process described by Lazarus, which we defined as caregivers’ perceived pressure from informal care [26]. Perceived pressure refers to the demands of the caregiving situation in proportion to caregivers’ personal interests, that is the necessary time and space for noncare-related thoughts, activities and roles of the caregiver. It is measured independently from caregivers’ (mental) health.
2. Methods
2.1. Sample We selected 175 demented elderly people and their informal caregivers. All elderly people lived in or near Amsterdam, the Netherlands, and none of them were institutionalized. All caregivers satisfied the following conditions: (1) providing care to the
A.M. Pot et al. / Patient Education and Counseling 34 (1998) 43 – 51
demented elder (personal care, instrumental care and / or supervision); (2) face-to-face contact with the elder at least once every 2 weeks; (3) receiving no financial compensation. If more than one caregiver was involved, the caregiver providing the most care was selected whenever possible. Trained interviewers interviewed subjects during home visits, with the aid of a laptop computer and left questionnaires to be completed and returned by subjects. The baseline data were collected between July 1991 and January 1993. Subjects were derived from two sources: the Amsterdam Study of the Elderly (AMSTEL), an epidemiological study on cognitive decline and dementia; and health care facilities. These two sources enabled us to select demented elderly subjects with various degrees of dementia and helpseeking as well as non-help-seeking demented eldercaregiver dyads. AMSTEL drew an age-stratified sample of elderly people (aged 65–84) from the patient registers of 30 general practitioners in Amsterdam. In total, 4051 elderly people participated in AMSTEL. A subsample was selected from the screening study for a diagnostic study. For more details on the design and sampling methods of AMSTEL, we refer to Jonker and Hooijer [30] and Launer et al. [31] Through AMSTEL, we selected informal caregivers for elderly people diagnosed as having minimal to severe dementia according to the Cambridge Mental Disorders of the Elderly Exam (CAMDEX) [32]. This diagnosis and classification corresponds to the DSM-III-R criteria of dementia. In addition, the CAMDEX guidelines include the category ‘minimal dementia’. All minimally demented elderly people had memory complaints and were suspected of having dementia according to the DSM-III-R criteria. Health care facilities were used as a second source for recruitment: four psychogeriatric day hospitals and an outpatient memory clinic in Amsterdam. Elderly attending a psychogeriatric day hospital were diagnosed as having dementia by an affiliated nursing home physician using DSM-III-R. Subjects referred from the memory clinic were diagnosed by a psychiatrist or neurologist also using DSM-III-R. Whereas caregivers of minimally or mildly demented elderly people were selected in particular through AMSTEL (N 5 75), the majority of elderly people referred from
45
psychogeriatric day hospitals and the memory clinic (N 5 100) were mildly or moderately demented.
2.2. Measures As no Dutch instruments with satisfactory psychometric properties were available, we developed measures of care-recipient behavioral problems as perceived by the caregiver, caregiving tasks and caregiving appraisal. The measure of behavioral problems consisted of 14 items, including being unsafe at home alone, unable to take part in normal conversation, restless or wandering during the day, losing or hiding things. For composing the item pool, English questionnaires were used [33,34]. Caregivers were asked to score the frequency of the behavioral problems on a sevenpoint scale. The total scores ranged 16–86 (M 5 48.4; SD 5 16.4; alpha 5 0.83). The instrument for measuring caregiving tasks comprised 21 tasks. Caregivers were asked to score the frequency of each task on a seven-point scale. The tasks concerned (Instrumental) Activities of Daily Living, derived from Katz et al. [35] and Lawton and Brody [36], and supervision. The total scores on this scale ranged 24–143 (M 5 78.1; SD 5 27.8; alpha 5 0.89). In order to measure caregiving appraisal, we developed an instrument to measure Self-Perceived Pressure from Informal Care (SPPIC: see appendix A). Perceived pressure refers to the demands of the caregiving situation in proportion to caregiver’s personal interests. These interests refer to caregiver’s need for non-care-related thoughts, activities, and roles. Half of the statements were derived from the questionnaire care stress of Janssen and Woldringh [26]. The SPPIC items were scored on a five-point scale. A nine-item Rasch scale was developed, with a satisfactory index of subject separation of 0.66 (which indicates how well items discriminate between subjects) and a reliability (Rho) of 0.79 [26]. Rasch analysis was used instead of more conventional statistical methods like factor analysis, because we wanted to differentiate between caregivers who perceived more pressure and those who perceived less pressure. Our underlying hypothesis was that self perceived pressure from informal care was a one-dimensional latent variable, varying from less to
A.M. Pot et al. / Patient Education and Counseling 34 (1998) 43 – 51
46
more pressure. This hypothesis was confirmed with the aid of Rasch analysis [37]. An important aspect of the SPPIC should be emphasized, especially in connection to the focus of this study, which is to test mediator effects of caregiving appraisal for the relationship between stressors and caregivers’ well-being. SPPIC items do not ask caregivers to relate their psychological distress directly to stressors in the caregiving situation. Thus, cause and effect are not entangled, cf. [38]. Caregivers’ psychological distress was measured using a Dutch translation of the 12-item version of the General Health Questionnaire (GHQ), which has good psychometcic properties [39,40]. Reliability coefficients (Cronbach’s alpha) range from 0.86– 0.97.
2.3. Data analysis To test mediation we followed the procedure formulated by Baron and Kenny [41]. The following regression models were estimated for the outcome variable. The hypothetical mediator (appraisal) was regressed on the stressor (behavioral problems or caregiving tasks), the outcome variable (psychological distress) was regressed on the stressor, and the outcome variable was regressed on both the hypothetical mediator and the stressor. According to Baron and Kenny, the following conditions must be met to establish mediation: first, the stressor must affect the hypothetical mediator in the first regression equation; second, the stressor must be shown to affect the outcome variable in the second regression equation; third, the hypothetical
mediator must affect the outcome variable in the third regression equation. Mediation occurs if the effect of the stressor on the outcome variable is smaller when the mediator is controlled. Perfect mediation means that the stressor has no effect on the outcome variable when the mediator is controlled [41].
3. Results Respondents who missed one of the scores on stressors, mediator or outcome measure were excluded from the analyses (N 5 17). Thus, data of 158 informal caregivers were analyzed. Approximately half of the caregivers were spouses (53.2%), the majority of whom were female (59. 5%). All spouses lived with the demented patient and only one spouse caregiver was employed (1.2%). Their mean age was 73.1 years, while the mean age of care-recipients was 75.6 years. As expected, characteristics of nonspouse caregivers (35% children) were somewhat different from those of spouse caregivers. Nonspouses were younger (50.6 years), more likely to be employed (37.8%) and primarily not sharing a household with the person they cared for (86.5%). Furthermore, non-spouse caregivers cared for relatively few male care-recipients (8.1%). Table 1 shows the mean scores of spouses and non-spouses on stressors, mediator and psychological distress. Spouse caregivers reported less behavioral problems for their demented care-recipients and higher levels of caregiving tasks, as compared to non-spouse caregivers. They also tended to score
Table 1 Means and standard deviations for stressors, mediator and outcomes for spouse and non-spouse caregivers respectively Spouse caregivers (N 5 84)
Measure
Behavioral problems Caregiving tasks b Perceived pressure GHQ-12 c a
a
, t 5 2 2.94, df 5 156, P 5 0.004. , t 5 4.46, df 5 156, P 5 0.000. c , t 5 1.92, df 5 156, P 5 0.057. b
Non-spouse caregivers (N 5 74)
M
SD
M
SD
45.2 87.0 4.8 4.7
(15.4) (28.8) (2.3) (3.8)
52.8 68.1 5.1 3.6
(16.7) (23.5) (2.7) (3.5)
A.M. Pot et al. / Patient Education and Counseling 34 (1998) 43 – 51
47
3.2. Mediator effect of caregiving appraisal
higher on psychological distress as measured using the GHQ-12.
For both spouses and non-spouses, the mediator effect of perceived pressure was tested for the combination of behavioral problems and the GHQ-12 and the combination of caregiving tasks and the GHQ-12, because there appear to be a significant association for both groups. For non-spouse caregivers, the mediator effect of perceived pressure could be confirmed for both associations (see Table 3). When the mediator (perceived pressure) was included in the model, the previously significant associations between these stressors and psychological distress were greatly reduced and no longer significant. For spouse caregivers, perceived pressure appeared to be a mediator in the association between their caregiving tasks and the score on the GHQ-12; however, the association between behavioral problems and the GHQ-12 was not mediated by perceived pressure (see Table 3). The stressor ‘behavioral problems’ retained its main effect on the psychological distress of spouse caregivers, whereas
3.1. Bivariate correlations Pearson product–moment correlations between behavioral problems, caregiving tasks, perceived pressure and psychological distress for spouse and non-spouse caregivers are shown in Table 2. For both spouse and non-spouse caregivers, behavioral problems and caregiving tasks correlated positively with their scores on the GHQ-12. Thus, more behavioral problems of the demented care-recipient and more caregiving tasks were associated with more psychological distress. For both groups, the putative mediator ‘perceived pressure’ was also correlated with the GHQ-12 score, indicating that more perceived pressure corresponds to more psychological distress. Strong associations were found between perceived pressure and psychological distress, especially for non-spouse caregivers.
Table 2 Correlations for stressors, mediator and outcomes for spouse and non-spouse caregivers Measures
Behavioral problems
Caregiving tasks
Perceived pressure
GHQ-12
Behavioral problems Caregiving tasks Perceived pressure GHQ-12
– 0.24 a 0.45 b 0.23 a
0.60 b – 0.46 b 0.26 a
0.60 b 0.58 b – 0.50 b
0.44 b 0.24 a 0.39 b –
a
, P , 0.05. , P , 0.001. Correlations for spouses are above the diagonal, correlations for non-spouses are below the diagonal. b
Table 3 Mediator effect of appraisal tested for associations between stressors and the caregivers’ score on the GHQ-12: regression results Non-spouse caregivers (N 5 74)
Behavioral problems Perceived pressure Caregiving tasks Perceived pressure a
R2
– 0.25
0.33a 0.19
– 0.22
– 0.25
0.02 0.38 b
– 0.15
R
2 0.00 0.50
, P , 0.05. , P , 0.01. c , P , 0.001. R 2 is total variance explained by stressor and mediator. b
b
b
0.03 0.49 c
Spouse caregivers (N 5 84) 2
48
A.M. Pot et al. / Patient Education and Counseling 34 (1998) 43 – 51
the impact of perceived pressure on psychological distress was reduced and no longer significant.
4. Discussion The results of this study showed mediator effects of caregiving appraisal as measured by perceived pressure from informal care, in three out of four associations between stressors and caregivers’ psychological distress. This indicates that the effects of stressors on caregivers’ psychological distress in the caregiving situation, can be explained by the fact that caregivers have (too) little time and space for noncare related thoughts, activities and roles. The prominent mediator effects of perceived pressure on nonspouse caregivers’ psychological distress are particularly notable. However, there is one exception that also requires attention and stresses the importance of differentiating between spouse and nonspouse caregivers for investigating the mediator effects of appraisal in the caregiving stress process. For spouse caregivers, perceived pressure did not mediate the association between demented care-recipients’ behavioral problems, such as their being suspicious, hiding things, behaving in an embarrassing or unusual way, or their inability to take part in normal conversation, and spouse caregivers’ psychological distress. Thus, spouse caregivers did not report more psychological distress because they could not think of anything else or had little opportunity for other activities or roles due to demented spouses’ behavioral problems. Strong associations of behavioral problems with distress remained, while associations of perceived pressure with distress were greatly reduced. Contrary to our results, Lawton et al. did find a mediator effect of caregiving appraisal for the relationship between symptoms of demented elderly care-recipients and depression of spouse caregivers [29]. However, whether their measure of caregiving appraisal (burden) can be viewed as a complete mediator is questionable, because it was strongly correlated with the outcome measure (depression) (r 5 0.63). It included affective responses (i.e. (mental) health problems) to the demands of the caregiving situation. The finding of Haley et al. that caregivers’ appraisal of stressfulness mediates the effect of caregiving stressors on their depression is
difficult to compare with our findings [19]. Caregiving stressors included not only behavioral problems, but also patients’ ADL and IADL impairment and no difference was made between spouse and non-spouse caregivers. The results of our study emphasize the importance of distinguishing different kind of stressors and caregivers. A question arises concerning why demented spouses’ behavioral problems affect caregiving spouses’ psychological distress without mediation of perceived pressure. An explanation may be that behavioral problems poses (too) great demands on the quality of the spousal relationship for caregiving spouses. Another explanation for the association between behavioral problems and spouses’ psychological distress may be that spouse caregivers are less capable of stepping back from the caregiving situation and maintaining a feeling of control with respect to their demented spouses’ behavioral problems, merely because they share a household with the demented elderly person. In addition to Lazarus’ stress model, Pearlin’s model on the caregiving stress process also describes a mediating process between stressors and outcomes [42]. In this model, primary stressors affect secondary role strains, which in turn affect secondary intrapsychic strains. Intrapsychic strains affect outcomes such as caregivers’ depression of the caregiver. For example, family conflicts and job–caregiving conflicts are indicators of secondary role strains, and role captivity and loss of self are indicators of secondary intrapsychic strains. Relational deprivation and overload are included as subjective indicators of primary stressors. For this model, main effects rather than mediator effects were tested [43,44]. Our measure of caregiving appraisal touches some of the concepts of this theory as the examples indicate. Thus, the mediator effects of perceived pressure found in our study lead us to expect mediator effects of Pearlin and colleagues’ measures of the mediating process between caregiving stressors and outcomes [42]. Information on the severeness and duration of the disease and its effects on caregivers’ distress was not included in this study. In most previous studies the general severity of dementia is not associated with indicators of caregivers’ burden or psychological well-being. For testing the mediator effect of
A.M. Pot et al. / Patient Education and Counseling 34 (1998) 43 – 51
caregiving appraisal, stressors with a strong association with caregivers’ psychological well-being are needed. Results of previous studies show that patients’ behavioral problems are most strongly associated with caregivers’ psychological well-being in comparison with other indicators of dementia [1].
5. Practice implications The relevance of the findings on the mediator effect of perceived pressure is that they clarify the caregiving stress process and indicate what should be a focus for interventions to prevent or delay the deteriorating psychological well-being of informal caregivers. For both non-spouse and spouse caregivers, it is inadequate to direct interventions merely at stressors, i.e. the behavioral problems of demented care-recipients or the caregiving tasks carried out by caregivers. Reducing confrontation with behavioral problems or caregiving tasks by, for instance, respite care may not be enough. What is also needed is a reduction of perceived pressure from informal care. For example, caregivers can be taught to create more time for themselves or for other activities and roles, or taught conflict management in order to reduce family or work conflicts, using such techniques as training in management skills and assertiveness training. Management-skills training is already part of intervention studies, e.g., [45]. Based on our findings, we may expect these kinds of interventions to reduce non-spouse caregivers’ psychological distress in particular.
Acknowledgements This project was supported by a grant from the University Stimulation Fund, Amsterdam, and the Prevention Fund, The Hague, the Netherlands.
Appendix 1 Items concerning ‘ Self-perceived Pressure from Informal Care’ ( SPPIC): Translated in English 1. Owing to the situation of my... I have too little time for myself
49
2. Combining the responsibility for my... and for my job and / or family is not easy 3. Because of my involvement with my... I don’t pay enough attention to others 4. I must always be available for my... 5. My independence is suffering 6. The situation of my... constantly demands my attention 7. Because of my involvement with my... I am getting into conflicts at home and / or at work 8. The situation of my.. is a constant preoccupation 9. Generally speaking I feel very pressured by the situation of my... Items concerning ‘ Self-perceived Pressure from Informal Care’ ( SPPIC): Original Dutch version 1. Door de situatie van mijn .. kom ik te weinig aan mijn eigen leven toe 2. Het combineren van de verantwoordelijkheid voor mijn .. en de verantwoordelijkheid voor mijn werk en / of gezin valt niet mee 3. Door mijn betrokkenheid bij mijn .. doe ik anderen tekort 4. Ik moet altijd maar klaarstaan voor mijn .. 5. Mijn zelfstandigheid komt in de knel 6. De situatie van mijn .. eist voortdurend mijn aandacht 7. Door mijn betrokkenheid bij mijn .. krijg ik konflikten thuis en / of op mijn werk 8. De situatie van mijn .. laat mij nooit los 9. Ik voel me over het geheel genomen erg onder druk staan door de situatie van mijn ..
References [1] Pot AM, van Dyck R. Belastende factoren in de zorg voor een dement familielid: een literatuuroverzicht [The impact of care for a demented family member: a review of the literature]. Tijdschr Psychiatr 1992;34:627–36. [2] Anthony-Bergstone CR, Zarit SH, Gatz M. Symptoms of psychological distress among caregivers of dementia patients. Psychol Aging 1988;3:245–8. [3] Bodnar JC, Kiecolt-Glaser JK. Caregiver depression after bereavement: chronic stress isn’t over when it’s over. Psychol Aging 1994;9:372–80. [4] Cohen D, Eisdorfer C. Depression in family members caring for a relative with Alzheimer’s disease. J Am Geriatr Soc 1988;36:885–9.
50
A.M. Pot et al. / Patient Education and Counseling 34 (1998) 43 – 51
[5] Coppel DB, Burton C, Becker J, Fiore J. Relationships of cognitions associated with coping reactions to depression in spousal caregivers of Alzheimer’s disease patients. Cogn Ther Res 1985;9:253–66. [6] Fitting M, Rabins P, Lucas MJ, Eastham J. Caregivers for dementia patients: a comparison of husbands and wives. Gerontologist 1986;26:248–52. [7] Gilleard CJ, Belford H, Gilleard E, Whittick JE, Gledhill K. Emotional distress amongst the supporters of the elderly mentally infirm. Br J Psychiatr 1984;145:172–7. [8] Haley WE, Levine EG, Brown SL, Berry JW, Hughes GH. Psychological, social, and health consequences of caring for a relative with senile dementia. J Am Geriatr Soc 1987;35:405–11. [9] Morris LW, Morris RG, Britton PG. The relationship between marital intimacy and perceived strain and depression in spouse caregivers of dementia sufferers. Br J Med Psychol 1988;61:231–6. [10] Pot AM, Deeg DJH, van Dyck R. Psychological well-being of informal caregivers of elderly people with dementia. Aging Ment Health 1997;1:261–8. [11] Pruchno RA, Potashnik SL. Caregiving spouses. Physical and mental health in perspective. J Am Geriatr Soc 1989;37:697–705. [12] Eagles JM, Craig A, Rawlinson F, Restall DB, Beattie JAG, Besson JAO. The psychological well-being of supporters of demented elderly. Br J Psychiatr 1987;150:293–8. [13] Harper S, Lund DA. Wives, husbands, and daughters caring for institutionalized and noninstitutionalized dementia patients: toward a model of caregiver burden. Int J Aging Hum Dev 1990;30:241–62. [14] Pruchno RA, Resch NL. Mental health of caregiving spouses: coping as mediator, moderator, or main effect?. Psychol Aging 1989;4:454–63. [15] Schulz R, Williamson GM. A 2-year longitudinal study of depression among Alzheimer’s caregivers. Psychol Aging 1991;6:569–78. [16] Lazarus RS, Folkman S. Stress, appraisal, and coping. New York: Springer Publishing Company, 1984. [17] Lazarus RS. Emotion and adaptation. New York: Oxford University Press, 1991. [18] Haley WE, Brown SL, Levine EG. Family caregiver appraisals of patient behavioral disturbance in senile dementia. Clin Gerontol 1987;6:25–34. [19] Haley WE, Roth DL, Coleton MI et al. Appraisal, coping, and social support as mediators of well-being in black and white family caregivers of patients with Alzheimer’s disease. J Consult Clin Psychol 1996;64:121–9. [20] Kasper JD, Steinbach U, Andrews J. Caregiver role appraisal and caregiver tasks as factors in ending caregiving. J Aging Health 1994;6:397–414. [21] Please supply copy for this ref. [22] Kinney J, Stephens MAP. Caregiving hassles scale: assessing the daily hassles of caring for a family member with dementia. Gerontologist 1989;29:328–32. [23] Vitaliano PP, Russo J, Young HM, Becker J, Maiuro RD. The screen for caregiver burden. Gerontologist 1991;31:76–83.
[24] Teri L, Truax P, Logsdon R, Uomoto J, Zarit S, Vitaliano PP. Assessment of behavioral problems in dementia: the revised memory and behavior problems checklist. Psychol Aging 1992;7:622–31. [25] Lawton MP, Kleban MH, Moss M, Rovine M, Glicksman A. Measuring caregiving appraisal. J Gerontol 1989;44:P61–71. [26] Pot AM, vanDyck R, Deeg DJH. Ervaren druk door informele zorg: constructie van een schaal [Self-perceived pressure from informal care: construction of a scale). Tijdschr Gerontol Geriatc 1995;26:214–9. [27] Haley WE, Levine EG, Brown SL, Bartolucci AA. Stress, appraisal, coping, and social support as predictors of adaptational outcome among dementia caregivers. Psychol Aging 1987;2:323–30. [28] Kinney J, Stephens MAP. Hassles and uplifts of giving care to a family member with dementia. Psychol Aging 1989;4:402–8. [29] Lawton MP, Moss M, Kleban MH, Glicksman A, Rovine M. A two-factor model of caregiving appraisal and psychological well-being. J Gerontol 1991;46:P181–9. [30] Jonker C, Hooijer C. The Amstel project: design and first findings: The course of mild cognitive impairment of the aged; a longitudinal 4-year study. Psychiatr J 1990;25:207– 11. [31] Launer LJ, Dinkgreve MAHM, Jonker C, Hooijer C, Lindeboom J. Are age and education independent correlates of the Mini-Mental State Exam performance of communitydwelling elderly?. J Gerontol 1993;48:P271–7. [32] Roth M, Tym E, Mountjoy CQ et al. CAMDEX. A standardized instrument for the diagnosis of mental disorder in the elderly with special reference to the early detection of dementia. Br J Psychiatr 1986;149:698–709. [33] Gilleard CJ. Living with dementia. Community care of the elderly mentally infirm. London: Croom Helm, 1984. [34] Levin E, Sinclati I, Gorbach P. Families, services and confusion in old age. Aldershot: Avebury, 1989. [35] Katz S, Ford AB, Moskowitz RW, Jackson BA, Jaffe MW. Studies of illness in the aged. The index of ADL: a standardized measure of biological and psychosocial function. J Am Med Assoc 1963;185:914–9. [36] Lawton MP, Brody EM. Assessment of older people: selfmaintaining and instrumental activities of daily living. Gerontologist 1969;9:179–86. ¨ [37] Niemoller C, Schuur van WH. Stochastic models for unidimensional scaling: Mokken and Rasch. In: McKay D, Schofield N, Whiteley P, editors. Data analysis and the social sciences. London: Frances Pinter, 1983:120–170. [38] George L.K., Gwyther L.P. Caregiver well-being: a multidimensional examination of family caregivers of demented adults. Gerontologist 1986; 26: 253–259. [39] Goldberg DP, Williams P. A users guide to the General Health Questionnaire. Windsor: Nfer Nelson, 1988. [40] Koeter MWJ, Ormel J. General Health Questionnaire, Nederlandse bewerking handleiding [General Health Questionnatie, Dutch version manual). Lisse: Swets and Zeitlinger, 1991. [41] Baron RM, Kenny DA. The moderator-mediator variable
A.M. Pot et al. / Patient Education and Counseling 34 (1998) 43 – 51 distinction in social psychological research: conceptual, strategic, and statistical considerations. J Person Soc Psychol 1986;51:1173–82. [42] Pearlin LI, Mullan JT, Semple SJ, Skaff MM. Caregiving and the stress process: an overview of concepts and their measures. Gerontologist 1990;30:583–94. [43] Semple SJ. Conflict in Alzheimer’s caregiving families: its
51
dimensions and consequences. Gerontologist 1992;32:648– 55. [44] Skaff MM, Pearlin LI. Caregiving: role engulfment and the loss of self. The Gerontologist 1992;32:656–64. [45] Brodaty H, Gresham M. Effects of a training programme to reduce stress in carers of patients with dementia. Br Med J 1989;299:1375–9.