Our findings showed a general tendency for the nursing staff to rate the QoL of residents with dementia as higher than their associated family members do. However, significant differences do not exist across all QoL dimensions. There is variation not only in the average ratings between the two rater groups but also in the extent of agreement between them. For some dimensions, the share of identical ratings and the ICCs are substantially higher than for others. Finally, differences in the average ratings and the agreement, as indicated by the ICCs, seem related, but also show some variation across the QoL dimensions.
For care relationship, we found no significant deviation in means, a strong proportion agreement and a good agreement when we calculated the ICCs, and no significant difference between family member and nursing staff agreement in the combined regression analyses. From this we conclude that the greatest agreement between the nursing staff and family members exists in the assessment of care relationship. For all other dimensions, we found different combinations of significant deviations in means, low proportion agreement, poor to moderate agreement when we calculated the ICCs, and a significant difference between the two groups in the regression analyses. Obviously, the level of QoL assessments depends on whether they were made by the nursing staff or by the family members.
Proxy-ratings for residents’ quality of life
Our results show that the assessment of resident’s QoL tends to be higher when performed by the nursing staff. Higher nursing staff assessments, compared to family members’ assessments, are in line with the findings of other studies [3,13,15,38]. However, Castro-Monteiro et al.  and Clare et al.  used an aggregated score for QoL and therefore did not differentiate between QoL dimensions. Crespo et al.  used the QOL-AD and assessed differences in ratings on the item level. For the 15 items, they found significantly higher scores given by the staff for six items (“physical health”, “energy”, “mood”, “memory”, family”, “ability to take care of himself/herself”) and a significantly higher score by the family members in one case (“ability to do things for fun”). As these items cover distinct topics compared to the items comprising the QUALIDEM dimensions, the results are hardly comparable, and our study provides some additional insights. One potential explanation for the higher nursing staff ratings relies on different perspectives and expectations between the two rater groups. The nursing staff might answer questions regarding QoL while focusing on residents with a more progressive dementia disease, while family members may assess the residents’ current QoL in relation to a former status when psycho-geriatric services had not been necessary [13,14]. Additionally, the residents’ observable behavior may differ when they are being visited by a family member than when they have everyday interactions with the nursing staff.
Factors influencing quality of life
Regarding predictors of QoL, we found that functional independence and fewer challenging behaviors and nursing home suitability were associated with higher QoL among residents; this finding is also consistent with those of prior studies. Functional independence is usually associated with higher QoL or related factors, such as well-being [39,40], while challenging behaviors, such as depression, anxiety, and agitation, are associated with lower QoL [7,21–22,25]. Our study shows that the results of prior research also hold true in the context of German nursing homes, and additionally, addresses how functional independence, challenging behaviors, and the nursing home suitability are related to the various QoL dimensions depending on the dimensions and the rater group.
Our results also show that for the QoL assessment the relevance of functional independence, challenging behavior, and nursing home suitability differs vastly between the two rater groups. The nursing staff attached great importance to residents’ functional independence and the number of challenging behaviors and some importance to the nursing home suitability. In contrast, family members’ QoL assessments seemed to be mostly independent of residents’ functional independence, the number of challenging behaviors, and the nursing home suitability. For them only one QoL dimension, namely less tense behavior, was associated with one predictor variable: functional independence.
Overall, functional independence was most frequently found to have a significant effect on residents’ QoL and should be promoted due to its positive effect. Enabling residents to participate in nursing home activities and helping them to maintain contact with other residents, nursing staff, and visitors might have resulted in a higher QoL score for social relations. Additionally, functional independence was associated with a more frequent display of positive affect. Residents might feel more comfortable, and therefore display more signs of being content and cheerful, when they are able to regulate their toileting and bathing themselves.
Challenging behaviors were significantly negatively associated with care relationship, negative affect, restless tense behavior, and social isolation. In particular, agitation and irritability can complicate the care relationship between residents and nursing staff, while aberrant motor behavior, as a component of challenging behaviors, can lead to more restless tense behavior. At the same time aberrant behavior can lead to social isolation by means of residents rejecting contact with others, or being rejected.
For both factors, functional independence and challenging behaviors, the question might be whether they are actually linked to residents’ QoL, or whether both are used as a 'proxy' in the assessment of QoL, so that raters simply assume that residents with lower functional abilities and more challenging behaviors must have a lower QoL. While it is possible that raters’ assessments are influenced by those factors, we also believe that the QUALIDEM’s response scale (how often raters observed specific behaviors of residents over the last two weeks, such as smiling or calling out) offers the objectivity needed to rate QoL independently.
In the literature, the influence of nursing home characteristics, such as the spatial and process suitability of the nursing home and sufficient staffing levels, has not yet been conclusively clarified. It is to be expected that nursing homes focusing on the care of residents with dementia will be able to adapt their care processes, premises, and their resident and staff composition and thus offer a better working and living environment, which in turn can benefit the QoL of the residents. In addition, nursing staff who is specialized in caring for residents with dementia may be more experienced and more confident in working with this group of residents. To add to the literature, we included nursing home suitability as a third predictor and found a significant positive association on social isolation, but only in the nursing staff assessments. However, the instrument used in this study combining nursing home characteristics and staffing levels cannot be directly compared to instruments used in prior research.
Our results indicate that promoting functional independence, reducing the prevalence of challenging behaviors, and a better nursing home suitability is associated with higher QoL for nursing home residents. Nursing homes should therefore promote measures that help residents maintain or regain functional independence and also create an environment that supports an adequate approach to deal with or reduce challenging behaviors. The systematic measurement of functional independence and challenging behavior with validated instruments might be a good starting point to identify residents who display challenging behaviors and whose functional independence might be improved by training and therapy.
At the same time, QoL assessments are a useful way to identify areas where quality of care and QoL in the long-run can be improved. Low scores for the care relationship, for example, can hint at ongoing conflicts between the nursing staff and residents, while low scores for social isolation can reveal that attempts should be made to promote interactions between residents. In addition, a cooperation between nursing homes and external organizational units, e.g. church groups or schools, could be beneficial to combat social isolation.
An inclusion of the residents’ family members may provide an assessment of QoL from a different perspective. While similar assessments between both groups could serve as a validation, deviations might open a discussion about expectations and appropriate measures to reduce them. This approach can result in concrete actions for each resident while accounting for the different perspectives and individual characteristics of residents in terms of personality, type and severity of illness, and general needs.
A regular assessment of residents’ QoL could remind the nursing staff of its multidimensional nature, the manner in which different dimensions should be addressed during the daily care process, and how QoL is changing over time for each resident specifically. However, in order for positive results to unfold, a process of QoL assessments, rounds of discussion, and derivations of recommendations for action must be conducted regularly. Nursing home care is often focused on physical care and food supply due to time pressures and high workloads, leaving less time for the staff to meet the other demands and needs of residents with dementia. Demands and needs such as social and physical contact, affection, and self-determination are independent of the presence of dementia. However, declining communication skills, impaired memory and judgement as well as personality changes of residents with dementia make it difficult for the staff to understand and fulfill those demands and needs. Thus, sufficient training and staffing are needed to respond to those situations and improve overall care.
Limitations and future research considerations
The limitations of our study are consistent with those of other papers in this area. Studies to investigate Qol in residents with dementia are usually cross-sectional and characterized by small sample sizes due to an old and multimorbid population [4,7,12]. When comparing the rater assessments for the same resident, more observations would have been desirable, and longitudinal data could have provided insight into the changes in the QoL of residents and the QoL assessments over time. Another difficulty is that data collection on site is cumbersome, involving nursing staff and family members. Finally, as with similar studies, the generalization of our results is limited by the particular setting of nursing homes and a potential self-selection bias [6-7,13].