3.1 | Aim
This study aims to explore the following questions: (1) What factors influence the positive aspects of caring for dementia patients by family caregivers? (2) Among the factors that influence the positive aspects of caring, what are the facilitators and barriers? (3) What are the dependent variables associated with the positive aspects of caring? (4) Among the factors that indirectly influence the positive aspects of caring, what are the mediators of the dependent variables?
3.2 | Design/methodology
A mixed-method systematic review that will include both quantitative and qualitative studies was chosen for its ability to find as many factors that influence the PAC as possible. This study intends to obtain a broader understanding of the PAC by integrating various approaches and analyzing and synthesizing the data, the findings of which will then be presented.
3.2.1 | Registration
This study protocol was registered with PROSPERO (CRD42022364445).
3.2.2 | Eligibility criteria
Both PEOS (population, exposure, outcome, study characteristics) and PICOS (population, phenomenon of interest, context, outcome, study characteristics) search strategy tools will be employed in this review to determine the eligibility criteria, as outlined in the following.
(1) Population
In this systematic review, eligible studies will be those that include caregivers of dementia patients as the population. Eligible participants include family caregivers of dementia patients in two settings—not stated or community-dwelling. “Family caregivers” are considered informal (i.e., unpaid) caregivers, such as spouses and adult children, who are currently providing caregiving support to patients with dementia.
(2) Exposure/phenomenon of interest
“Exposure” in this systematic review refers to the factors that are recognized as those associated with the PAC and their facilitators and/or barriers. For descriptive or phenomenological qualitative studies, if the objectives’ focus is on the feelings, experiences, and perspectives of the positive aspects of caring for dementia patients, they will be included.
(3) Context
Community-dwelling patients diagnosed with dementia will be included, whereas those with mild stages of disease progression from the outpatient/inpatient departments of geriatric psychiatry and neuropsychiatry and those receiving 24/7 care in institutions will be excluded.
(4) Outcome
The primary outcome of this systematic review will be the influencing factors of the positive aspects of caring, which are comprised of four domains: (1) personal accomplishment and gratification in the fulfillment of caregiving for others; (2) mutual support in the caregiver-patient relationship; (3) closer family ties and functionality; and (4) personal growth and finding a purpose in life. Therefore, the concepts of the PAC will include uplifting, gratification, rewarding, growth, satisfaction, etc. In line with the systematic review questions, various definitions/concepts/domains of the PAC proposed in the articles will be searched. Studies that measured outcomes from various data sources, including self-reporting, will be extracted for further consideration.
(5) Study characteristics
Mixed-methods study designs—cross-sectional, cohort, and case-control studies—will be included, while reviews will be excluded for their lack of strong evidence. Randomized controlled trials will also be excluded as they are more likely to focus on the effectiveness of interventions. Due to available resources and feasibility, only articles reported in the English language, with the limitation of the timeframe of 1997 to the present, will be included.
3.2.3 | Information sources
Peer-reviewed studies found in the electronic bibliographic databases of PubMed, Web of Science, PsycINFO, EMBASE, and the Cochrane Central Register of Controlled Trials will be searched from 1997, when the topic was first identified [3], to the present. Unpublished information sources in gray literature databases, such as Proquest Dissertations & Theses Global and OpenGrey, as well as the clinical trial databases of ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform, will also be searched for valid studies. The reference lists of the extracted studies will be scanned to confirm the saturation of literature, and the search procedure will be updated to ensure the retrieval of as many eligible studies as possible. Finally, a search of the authors’ personal files will be made to obtain any remaining material relevant to the search.
3.2.4 | Search strategy
The four main search concepts will be factor, dementia, caregiver, and positive aspects. An initial search of the medical subject headings and text words related to the topic in each database and information source will be undertaken to find specific terms related to these concepts, and the titles, abstracts, and index terms used in the articles will be analyzed during the search strategy. Two researchers (LLC, MQZ) will conduct the title, abstract, and full-text screening independently. Table 1 illustrates the search concepts and the list of search terms, and Table 2 shows the results of the search strategy for one of the databases.
Table 1
Concepts of the review and the list of search terms that will be used in the literature search
| Factor Terms | Caregiver Terms | Dementia Terms | Positive Aspects Terms |
| Factor* Influenc* Relate* Predict* Relevan* Contribut* | Caregivers/ Carer* Caregiver* Care partner* Care provider* | Dementia/ Alzheimer* Cognitive decline Cognitive impairment/ Corticobasal degeneration/ Creutzfeldt Jakob syndrome/ Dementia with Lewy bodies/ Early onset dementia Frontotemporal dementia Frontotemporal lobar degeneration Late onset dementia Memory disorders/ Nerve Degeneration/ Neurodegenerative diseases/ Parkinson’s dementia Picks disease/ Semantic dementia/ Senile dementia/ Vascular dementia Young onset dementia MCI | Positive aspect* Positive experience* Positive feeling* Positive dimension* Positive emotion* Positive psychology/ Positive outcome* Caregiving benefit* Caregiving gain* Accomplishment gratification Autonomy/ Contentment/ Empowerment Reward/ Finding meaning Intrinsic motivation Life satisfaction/ Meaning/ Meaningfulness/ Motivation/ Optimism/ Persistence/ Posttraumatic growth/ Resilience/(psychological Satisfaction/ Self-affirmation Self-confidence/ Self-determination/ Self-efficacy/ Self-evaluation/ Self-perception/ Well-being/ |
Table 2
Search strategy and results in PubMed
| Number | Search Terms | |
| #1 | Factor* OR Influenc* OR Relate* OR Predict* OR Relevan* OR Contribut* | 12,658,232 |
| #2 | Caregivers [MeSH Terms] OR Carer* OR Caregiver* OR Care partner* OR Care provider* | 360,139 |
| #3 | Dementia [MeSH Terms] OR Corticobasal degeneration [MeSH Terms] OR Creutzfeldt Jakob syndrome [MeSH Terms] OR Frontotemporal dementia [MeSH Terms] OR Frontotemporal lobar degeneration [MeSH Terms] OR Memory disorders [MeSH Terms] OR Nerve Degeneration [MeSH Terms] OR Neurodegenerative diseases [MeSH Terms] OR Vascular dementia [MeSH Terms] OR Cognitive decline OR Late onset dementia OR Dementia with Lewy bodies OR Early onset dementia OR Cognitive impairment OR Alzheimer* OR Parkinson’s dementia OR Picks disease OR Semantic dementia OR Senile dementia OR Young onset dementia OR MCI | 675,671 |
| #4 | Empowerment [MeSH Terms] OR Reward [MeSH Terms] OR Motivation [MeSH Terms] OR Optimism [MeSH Terms] OR Resilience psychological [MeSH Terms] OR Self-efficacy [MeSH Terms] OR Positive psychology [MeSH Terms] OR Posttraumatic growth [MeSH Terms] OR Positive aspect* OR Positive experience* OR Positive feeling* OR Positive dimension* OR Positive emotion* OR Positive outcome* OR Caregiving benefit* OR Caregiving gain* OR Accomplishment gratification OR Autonomy OR Contentment OR Finding meaning OR Intrinsic motivation OR Meaning OR Meaningfulness OR Persistence OR Satisfaction OR Self-affirmation OR Self-confidence OR Self-determination OR Self-evaluation OR Self-perception OR Well-being | 10,774,883 |
| #5 | #1 AND #2 AND #3 AND #4 | 11,136 |
| #6 | Limit #5 to (English language and publication date “from 1997 to the present”) | 10,379 |
| #7 | Limit #6 to (observational study) | 195 |
| #8 | qualitative* OR phenomenology OR observation OR interview* | 4,724,326 |
| #9 | #6 and #8 | 3,708 |
| #10 | #9 or #7 | 3,823 |
3.2.5 | Data management and study selection
Identified articles will be downloaded to Endnote X20, which will be used to categorize, collate, and upload the identified citations; any duplicates found will be removed. Only the authors will have access to this password-protected file. Two researchers (LLC, MQZ) will independently screen the titles and abstracts first, followed by the full texts of the selected articles, to assess them against the inclusion criteria, and those of which do not meet the criteria will be excluded after they have been recorded and reported. If the two researchers encounter any disagreements during each stage of the selection process, they will be discussed until they are resolved. The results of the search process and study inclusion criteria will be shown in a flow diagram following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).
3.2.6 | Data extraction
Guidelines for data extraction will be developed to minimize errors during the extraction procedure and to facilitate the standardization of the process. Two researchers (LLC, MQZ) will independently conduct data extraction using standardized Joanna Briggs Institute (JBI) data extraction tools and the JBI System for the Unified Management of the Assessment and Review of Information software. The systematic review will be comprised of mixed-methods studies (i.e., both qualitative and quantitative studies), which will be recorded on a data extraction sheet. The data will include each study’s characteristics (i.e., author, country, publication year) and the study design/methods, population/participants, sample sizes, study settings, measurement tools, dependent/independent variables, factors, and primary outcomes. To ensure the accuracy of the data extraction, the eligible studies’ titles and abstracts will first be screened by two researchers (LLC, MQZ) independently for review. Any discrepancies will be resolved by a third researcher (JYZ). All the results will be presented and verified using tools such as forms and figures; for example, PRISMA flowchart, data extraction form, and quality assessment form.
For the quantitative studies, raw data will include specific details about the participants, study methods, and outcomes of significance. The qualitative studies’ data will include details such as population, setting, culture, geographic location, study methods, and the phenomena of interest relevant to the aim of the systematic review. In the mixed-method qualitative and quantitative studies, the factors and their perceived influence will be coded and subsequently recorded on the data extraction sheet. All extracted findings will be categorized based on the literature. When extracting the findings, the exact numbers and/or words will be reported without interpreting the data. If necessary, the authors of the eligible papers will be contacted to request missing or additional data for clarification.
3.2.7 | Quality appraisal assessment
After establishing the final list of references, the quantitative and qualitative mixed-methods studies selected will be critically assessed by two researchers (LLC, MQZ) independently. Prior to inclusion in the systematic review, the Newcastle-Ottawa Scale for case-control and cohort studies, as well as the JBI quality scale (i.e., “yes”, “no”, “unclear”, or “not applicable”) for cross-sectional studies, will be consulted. The Joanna Briggs Institute Critical Appraisal Checklist for Qualitative Research (CASP) will be used for the qualitative studies. For all the mixed-method studies, the Mixed Method Appraisal Tool will be used [23]. The eligible studies will be randomly selected by drawing lots, and then allocated to two researchers (LLC, MQZ) for quality appraisal assessment. Using Covidence functionality, inter-rater reliability for overlapping articles will be calculated. A “substantial” threshold of Kappa’s Cohen 0.61–0.80 will be set. Any disagreements encountered by the two researchers (LLC, MQZ) will be resolved through discussion or by a third researcher (JYZ). All studies will be subjected to data extraction and synthesis (when possible), and those that fail to meet the designated quality threshold will be excluded. The results will be presented in both narrative form and a table.
3.2.8 | Synthesis of results
The studies will be analyzed using a mixed-methods thematic synthesis, with the aim of integrating the results from both qualitative and quantitative research [24]. A confirmation synthesis will be undertaken to find out whether both types of studies address the same research question, and whether the same findings are repeated or refuted based on divergent findings [24]. Key differences in factors that emerged as influences on caregivers of dementia patients will be summarized. After comparing the quantitative and qualitative themes, how these findings confirmed or contradicted each other will be explored.
The findings of the qualitative studies will, when possible, use the meta-aggregation approach to generate a set of statements that will represent the aggregation by assembling the findings and categorizing them on the basis of similarity in meaning. These categories will then be synthesized into a single set of findings that will be used as a basis for evidence-based practice. The narrative form of the findings will be presented in the absence of textual pooling. The synthesis of results will include only unequivocal and credible findings. A configurative approach will be used for the synthesis of heterogeneous sources, which will be slotted together in an interpretive manner to expand and explain the sources, instead of confirming each source [25]. A mixed-methods synthesis table will be created; column headings will consist of one each of the four research questions guiding this review [26]. The segregated synthesis of the findings will be listed in their respective columns. The final synthesis of the quantitative and qualitative findings will produce a set of conclusions reflecting the narrative synthesis of the findings, which will then be used to configure the mixed-methods synthesis.
3.3 | Validity and reliability/rigor
To maintain rigor, a systematic review process will be followed [27]. The accuracy of the data (i.e., descriptive validity) will be maintained by the comprehensiveness of the search strategy and keeping a clear trail of search decisions. Interpretive validity will be maintained by the primary researchers’ viewpoints. Two reviewers will extract the data without interpretation, integrating all the study results as evenly as possible and considering the quality assessment to ensure that the conclusions were not overstated [28]. The credibility of the data interpretations (i.e., theoretical validity) will be maintained by keeping analytical memos of the interpretations and regular team discussions about the outputs of the synthesis. Finally, the utility and transferability of the findings (i.e., pragmatic validity) will be enhanced by providing data extraction tables, including the contexts of the studies, which will allow readers to judge the usefulness of the findings of the setting [28].