Influence of Facility Characteristics on the Quality of Life of Older Adult Residents: A Systematic Review

This review aims to obtain the relationships between characteristics of the facilities and the quality of life of older adult residents, and to obtain the direction in which new studies should be addressed as well as their application to healthcare policies. A systematic review was conducted following PRISMA guidelines. Multiple databases have been used: Scopus, Web of Science, Wiley online library, PubMed, ProQuest, EBSCOhost, and Emerald, from January 1, 2011 to July 1, 2023. Ten studies from 1,037 articles were included. Evidence exists on the positive relationships between quality of life and hours of management, care, activities, and qualified staff, and in general, the characteristics included in the categories of space management, supporting facilities and building services. In contrast charitable and for-profit facilities, Medicaid status, resident acuity, deficiencies, chain affiliation, size, hours of practical nurses, turnover, and financial resources (except occupancy rate) have a negative impact on quality of life or their dimensions.


Introduction
According to the WHO Quality of Life Assessment (WHOQOL) Group (1998), both psychological and social Well-Being (WB) are considered important dimensions of Quality of Life (QoL), along with physical health and the physical environment.
Moreover, there are different systems of care and protection for older adults across countries.In the context of this review, the broad concept of facility is restricted to protection systems for older adult residents which includes Long Term Care Facilities such as Nursing Homes and Assisted Living Facilities, as well as Care and Attention Homes.
The characteristics of the facilities, refer to organizational factors that provide residents with the opportunity to receive care.It basically contains two domains (Campbell et al., 2000): physical characteristics and staff characteristics.Physical and staff characteristics may influence QoL.Physical characteristics can improve QoL (e.g., private rooms).Staff can do things to improve QoL (e.g., satisfactory activities).Although these characteristics do not guarantee the care received or QoL, they have a direct impact on processes and outcomes (Campbell et al., 2000).
The association between facility characteristics and residents' QoL is a topic yet to be determined.It is true that previous work has been developed in which the literature has been systematically reviewed (Xu et al., 2013), this has highlighted the lack of studies in this topic.The study cited above covers papers from 1960 to March 2012 in the United States.On the other hand, studies such as Shin and Bae (2012) focus on the relationship between nurse staffing, QoL and quality of care also in the United States in a period from 1996 to 2011.
The research gap in studies examining the influence of facility characteristics on the QoL of older adult residents is notable.While there is a substantial body of research focused on factors like nurse staffing and care quality in residential facilities, there is a relative scarcity of comprehensive studies that specifically explore the relationship between facility characteristics and QoL outcomes.Many existing studies tend to emphasize aspects related to healthcare provision and clinical outcomes, often overlooking other important dimensions of facility characteristics.Understanding how these facility characteristics influence the QoL of older adult residents is crucial for developing effective interventions and improving the overall well-being of this population.By bridging this research gap and conducting more comprehensive studies that encompass a wide range of facility characteristics, we can gain valuable insights into the multifaceted nature of facility influence on residents' QoL.
By conducting such research, we can identify the specific facility characteristics that are most strongly associated with positive QoL outcomes for older adult residents.This knowledge can inform policy and practice decisions, guide facility design and management strategies, and ultimately enhance the overall living experience for older adults in residential settings.Therefore, further research focusing on the influence of various facility characteristics on the QoL of older adult residents is imperative to fill this research gap and contribute to the advancement of person-centered care in residential facilities.
Due to the lack of further studies, a systematic review of the literature on the characteristics of the facilities and their relationships with the QoL of older adult residents has been carried out from 2011 to the present.It should be known the relationships between facility's characteristics and QoL, their magnitude and significance, as well as to know the direction in which new studies should be focused.The review has considered not only the studies carried out in the United States, but also in other countries.We are aware that the characteristics of facilities and care systems differ between countries, and in many cases the results obtained in terms of QoL are not comparable.Nevertheless, it is important to know the characteristics of the facilities that influence the QoL in these countries or type of facilities, so that in some cases it is possible to establish a common link.Studies related to WB, Family satisfaction (FS) or dimensions associated to QoL, not just QoL, have been included, so throughout this article we can consider the term QoL to include the aforementioned terms or their dimensions.

Materials and Methods
A systematic literature review (Grant & Booth, 2009) was conducted to obtain the relationships between the characteristics of the facilities and the QoL of the older adult residents.This review was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines (Moher et al., 2009;Page et al., 2021).Protocol registered with PROSPERO, no.CRD42022347610.The CADIMA web tool (Kohl et al., 2018) was used to conduct the systematic review.This study did not need ethical approval as it performs a systematic review.

Search Strategy
The following databases were used in the searches performed on July 1, 2023 (Table 1): Scopus, Web of Science, Wiley online library, PubMed, ProQuest, EBSCOhost, and Emerald.The search included other databases such as MedLine, APA PsycInfo, Health & Medical Collection, Nursing & Allied Health Premium, among others (32 databases accessible through ProQuest), and CINAHL Complete, Global Health, among others (all accessible through EBSCOhost).
Terms and their related synonyms have been searched for to find studies concerning QoL or WB, facilities and their characteristics.For this, it has been necessary to carry out a previous review of articles related to this topic to find keywords that facilitate the determination of the key characteristics to be used in the searches.For example, keywords found were ''quality of life,'' ''nursing home,'' ''facility,'' ''setting,'' ''residential care,'' ''older adult,'' ''factor,'' ''indicator,'' ''parameter,'' ''characteristic,'' ''staffing,'' ''predictor,'' ''relationship,'' ''management,'' and so on, as well as synonymous and combination of these terms (Table 1).After this initial search, it was determined that the terms selected for searches would be included in the title of the articles, not being necessary to look for them in the abstract.In a test search with these terms in both, abstract and title, all the relevant studies extracted from a representative sample had the appropriate combination of terms in the title.

Eligibility Criteria
All titles and abstracts obtained in the search were independently screened by two authors, searching for the population, phenomenon of interest and context proposed.Discrepancies were resolved by a third author.In this step 36 studies were included for full-text revision attending to the inclusion and exclusion criteria decided by the authors.The inclusion criteria for the full-text revision were: (1) studies about characteristics associated with the facility structure, management, staffing, or services; (2) studies on facilities related to care services for older adult residents (3) studies about the influence of the facility's characteristics in QoL or its dimensions, the wellbeing or other related domains of the residents; (4) relevant studies published in journals or renowned conferences.As exclusion criteria were proposed: (1) studies about factors associated to the residents influencing QoL (active aging, healthy life, mental health, social health, etc.); (2) studies about mental illnesses (dementia, Alzheimer's, etc.) but not related to QoL; (3) studies about physical illnesses (such as cancer, diabetes, or incontinence) but not related to QoL; (4) studies about residential therapies, treatments, palliative care, or death and mourning; (5) studies of residential care for ethnic minorities or other collectives; (6) theses and dissertations; (7) studies where the full text was not available or in a language other than English or the native language of the authors.

Data Collection
Two authors gathered the characteristics of the studies and the main outcome of each one.A data extraction of relevant information of these studies was performed before the final assessment of all the studies selected.To complete this stage, the authors used a standardized data collection form, following the methodological recommendations proposed by Butler et al. (2016).The information extracted from each study was: title, authors, publication data, language, objective or aim, population, sample, methodology, type of study, QoL measure, characteristics of the facility, source of the facility characteristics, and the main outcomes related to QoL or their dimensions.Discrepancies were resolved by consensus, by means of a joint review between the authors.

Data Synthesis and Assessment of Quality
A narrative synthesis was used to identify the main findings of the studies included.Once the studies had been selected, a thematic analysis was carried out using the ''Thematic Synthesis'' protocol (Thomas & Harden, 2008) organizing in themes and subthemes and abstracting the findings related to characteristics of the facilities and the influence in QoL of the residents.The Thematic Synthesis was carried out simultaneously and independently by two authors, and the discrepancies that arose were resolved by consensus.
Two authors independently scored the criteria for the methodological quality of the studies included.The discrepancies that arose in the scoring and rating of the studies were resolved by consensus between them.Studies meeting the inclusion criteria were assessed for methodological quality using the assessment criteria developed by Kmet et al. (2004).The authors in common agreement established the thresholds for deciding the inclusion of the studies.

Results
The literature search and selection of studies can be seen in the PRISMA diagram in Figure 1.In the initial search, 1,037 documents were obtained from the databases.After the elimination of duplicates, 454 documents were obtained and passed to the screening phase.
The screening phase was performed in a randomized manner among the studies, in which 418 papers were removed after independent review by two authors of title and abstract to determine whether or not they met the PICo criteria.Discrepancies were resolved by a third author.A total of 36 studies were selected for full-text review.Of these, six studies were excluded because the full texts were not available or accessible.Of the remaining 30 studies, a total of 20 studies were excluded after applying the inclusion and exclusion criteria.Ten studies met the previously defined inclusion criteria.Finally, 10 studies were included in the content analysis.Although the review studies found have not been included in the results, they have been used as a reference to compare with the outcomes.A summary of the studies included can be found in Table 2.
After reviewing the studies finally included in this systematic review, the QoL measures used were first analyzed, following with the categorization of the characteristics of the facilities.Then, the different studies were analyzed, indicating the significance of each characteristic in relation to different measures of QoL or their dimensions (Table 3).

General Study Characteristics
Only relevant studies have been found from 2013 to 2017 and 2020, distributed over five different countries on three continents.The studies were quantitative research in eight different journals.Two of these studies were published in the journal Research on Aging, two in the Journal of Aging and Health and the remaining in other relevant publications.

Study Quality
A threshold of 75% has been established for the quality of the studies included in the review.All studies exceed this threshold, in a range between 75 and 100%.In general, item 4 ''subject characteristics sufficiently described,'' obtains the lower rating for three studies (Leung, Famakin, & Olomolaiye, 2017;Raes et al., 2020;Shin et al., 2014), due to the fact of not providing baseline/demographic information.Item 8, follows with a low rating for four studies (Kehyayan et al., 2016;Leung, Famakin, & Olomolaiye, 2017;Raes et al., 2020;Shin et al., 2014).In these studies, definitions of outcome measures are not reported in detail.Sample size is appropriate partially in other studies (Leung, Famakin, & Olomolaiye, 2017;Leung, Yu, & Chong, 2017;Shin et al., 2014), the sample seems small and there is no mention of the effect and variance estimated.The worst percentage of quality obtained was 75% (Leung, Famakin, & Olomolaiye, 2017;Shin et al., 2014) and the best was 100% (Shippee et al., 2017).The quality assessment of the studies included is shown in Table 4.

Previous Review Studies
Two studies have performed an analysis in similar terms to this review, one of them was a Systematic Review (Xu et al., 2013) and the other an Integrative Review (Shin & Bae, 2012).The first obtains results on the association between nursing home characteristics and QoL, including QoL measures used and facility characteristics (ownership, affiliation, chain membership, location, percentage of private rooms, facility size, and staffing).This study suggests an inconsistent association between nursing home characteristics and resident QoL.The second relates Nursing Staffing to Quality of Care and QoL in the U.S. Nursing Homes.Inconsistencies among the different studies were found, as the relationships between different levels of nurse-staffing skill mix and specific  structure, process, outcome, and compound quality indicators are not clearly defined.According to Xu et al. (2013), the paradigm to address Quality of Care can also be applied to QoL, so structural elements can improve QoL, staff can do specific things to improve QoL, and QoL and domains are outcomes.The study by Shin and Bae (2012) focuses on staff characteristics and their relationship with outcomes.

QoL Measurement
Various measures of QoL, as well as WB or FS, have been used in the studies included in this review.This gives us an idea of the most used standards when they have been related to the characteristics of facilities.
QoL definition by WHOQOL Group (1998) is used by Leung, Yu, and Chong (2017), Leung, Famakin, and Olomolaiye (2017).This measure covers the key physical, psychological, social, and environmental life domains.It refers to the subjective evaluation of individual overall life satisfaction and wellbeing.Include several dimensions: physical health, psychological health, social relationships, and their relationship to the salient features of their environment.In Leung, Famakin, and Olomolaiye, (2017) independence is included as an attribute to ensure autonomy.
The conceptual work by R. A. Kane et al. (2003), R. L. Kane et al. (2004) is used to measure QoL by Shippee, Hong, et al. (2015), Shippee, Henning-Smith, et al. (2015).They used their adaptation of QoL with six domains: environment, personal attention, food enjoyment, engagement, negative mood, and positive mood.A summary score was constructed that included all domains.In the same way, Shin et al. (2014) used 44 items to create 11 domains in a minimum data set.The self-reported QoL instrument was developed from a review of the literature, opinions of professionals, group discussion, and stakeholders' discussions (R. A. Kane et al., 2003).Domains cover comfort, functional competency, privacy, meaningful activity, autonomy, food enjoyment, spiritual WB, individuality, dignity, relationships, and security.On the other hand, Abrahamson et al. (2013) adapted the QoL survey with 35 items representing 10 equally-weighted domains, creating a composite measure of QoL based upon the domains of meaningful activities, autonomy, privacy, relationships, and individuality.
The interRAI Self-Report Nursing Home Quality of Life Survey consists of 11 domains with 4 to 6 items or components within each domain.These domains include access to services, activities, autonomy, comfort and environment, empowerment and support, food and meals, personal relationships, privacy, respect, safety and security, and staff-resident bonding.Raes et al. (2020) uses  this instrument to analyze the association between the price of the facility and the commented dimensions of QoL.Kehyayan et al. (2016) only uses an overall QoL of residents associated with the facility characteristics.Psychological and social WB are considered to be important dimensions of QoL, together with physical health and the physical environment (WHOQOL Group, 1998).Nordin et al. (2017) uses the psychological WB assessed by the World Health Organisation-5 Well-being index (WHO-5;Heun et al., 2001) and the resident's social WB by the Pleasant Events Schedule-AD (PES-AD; Logsdon & Teri, 1997).
Family members have a different perception and perspective on nursing home from residents.Usually, residents' perspective is required, while residents' opinion is the primary concern, increasing attention is given to the perspective of family members.Shippee et al. (2017) adapts the Zubritsky et al. (2013) model of QoL for selecting predictors of FS.The FS instrument was designed to correspond wherever feasible to measures in previously validated resident QoL surveys with items related to each of the domains with the exception of negative and positive moods.Four distinct domains were identified: care, staff, environment, and food.They do not match exactly, but refer to similar concepts to allow comparisons with residents QoL.
In the review by Xu et al. (2013), it is evident that the work of R. A. Kane et al. (2003), R. L. Kane et al. (2004) is taken as a reference to measure QoL of residents, adapted to 11, 10, and 7 domains.In addition to the above, many studies use the deficiencies in the Online Survey Certification and Reporting (OSCAR) data set.We must consider that this data set is specific to the United States and that the OSCAR system was replaced by the Certification and Survey Provider Enhanced Reporting (CASPER) system and the Quality   5.If interventional and random allocation was possible, was it described? 6.If interventional and blinding of investigators was possible, was it reported? 7. If interventional and blinding of subjects was possible, was it reported? 8. Outcome and (if applicable) exposure measure(s) well defined and robust to measurement / misclassification bias?Means of assessment reported? 9. Sample size appropriate? 10.Analytic methods described/justified and appropriate? 11.Some estimate of variance is reported for the main results? 12. Controlled for confounding? 13. Results reported in sufficient detail? 14. Conclusions supported by the results?This method uses 14 items to be scored depending on the degree to which the specific criteria are met (''yes'' = 2, ''partial'' = 1, ''no'' = 0).Items not applicable to a particular study design are marked ''n/a'' and are excluded from the calculation of the summary score.A summary score is calculated for each paper by summing the total score obtained across relevant items and dividing by the total possible score (i.e., 28-[number of ''n/a'' 3 2]).
Improvement Evaluation System (QIES) in mid-2012.The review by Shin and Bae (2012), does not include information on QoL metrics used, but does comment on the use of the OSCAR data set in some studies.

Facility Characteristics Classification
According to Campbell et al. (2000), structural characteristics in a health care service, can be categorized into two domains: physical characteristics and staff characteristics.Characteristics can be also categorized based on the study by Zubritsky et al. (2013).They contemplate structural characteristics, financial resources, and staffing and administrative resources (Shippee, Henning-Smith, et al., 2015).
On the other hand, structural characteristics can be subdivided into three groups, including space management, building services, and supporting facilities (Leung, Yu, & Chong, 2017).Space management denotes the management of available space taking into account the number of end users, their requirements, and the size allowances for personal and common areas (Robson et al., 1998).Building services are concerned with how the building functions and meets the needs of the older adults (Bitner, 1995).Supporting facilities aim to satisfy older adults and improve their QoL (Leung, Yu, & Chong, 2017).
Structural Characteristics.It is noted that ownership significantly predicts the overall QoL, in the case of municipal and private facilities with reference to charitable facilities (Kehyayan et al., 2016), as well as all the dimensions of FS in the case of government and non for profit facilities with reference to for profit facilities (Shippee et al., 2017).Non for profit facilities also predict the environment dimension of QoL (Shippee, Henning-Smith, et al., 2015).A stronger negative impact of resident acuity is observed in the summary QoL (Shippee, Hong, et al., 2015) and in the summary and all the dimensions of FS (Shippee et al., 2017).Deficiencies and chain affiliation have a negative effect on the summary and all the dimensions of FS (Shippee et al., 2017).All these findings are supported by three studies from one author (Shippee, et al., 2017;Shippee, Henning-Smith, et al., 2015;Shippee, Hong, et al., 2015).
There is a negative and significant contribution of the size (large size of the facility and number of beds) in the summary of QoL and FS measures and in some dimensions: personal attention, food enjoyment and engagement for QoL, and care, staff, environment and food for FS.These findings are supported by three studies from the same author (Shippee, et al., 2017;Shippee, Henning-Smith, et al., 2015;Shippee, Hong, et al., 2015).On the other hand, percent of private rooms contributes significantly and positively to the negative mood dimension of QoL (Shippee, Henning-Smith, et al., 2015).
In relation to location characteristic, we must be cautious.Although facilities located in rural areas compared to urban show an improvement in the overall QoL (Kehyayan et al., 2016), according to Shippee et al. (2017) there is less FS in all the dimensions considered.However, there is better FS in relation to care, environment and food in the case of facilities located in suburban areas (Shippee et al., 2017), but less FS in relation to staff.Facilities attached to a hospital are negatively associated with the environment dimension of QoL (Shippee, Henning-Smith, et al., 2015), but no other studies have been found for comparison.
Space Management Characteristics.Space identification contributes significantly and positively to some dimensions of QoL (Physical health and living environment).Distance contributes to social relationships (Leung, Yu, & Chong, 2017) and to psychological health and living environment (Leung, Famakin, & Olomolaiye, 2017).This fact does not give us a reliable and complete support of the dimensions it influences despite being indicated in two studies by the same author.Space identification is the only characteristic that contributes to the overall QoL.
Supporting Facilities Characteristics.All the characteristics related to supporting facilities with a significant impact (nonslip floor, furniture, recreation facilities, handrails, accessibility, doors and windows, and signage) have a positive relationship with QoL (Leung, Famakin, & Olomolaiye, 2017;Leung, Yu, & Chong, 2017), and in the case of cognitive support with the Social WB (Nordin et al., 2017).It should be noted that only one author in two studies considers the supporting facilities (Leung, Famakin, & Olomolaiye, 2017;Leung, Yu, & Chong, 2017).Recreation facilities obtain different relationships in the mentioned studies: with psychological health and living environment dimensions (Leung, Yu, & Chong, 2017) and with the overall QoL in Leung, Famakin, and Olomolaiye (2017).It is striking that both studies obtain different characteristics with significance related to QoL, except for the case of recreation facilities.
Building Services Characteristics.There are not a greater number of building services with significance related to QoL: ventilation, lighting, and water supply (Leung, Famakin, & Olomolaiye, 2017), the last with negative impact on some dimensions of QoL (psychological health and independence).Lighting and ventilation have a positive influence in the overall QoL, and in the dimensions of social relationships, independence and living environment.It is noteworthy that ventilation obtains relationships with different dimensions of QoL in two studies of Leung, Yu, and Chong (2017;Leung, Famakin, & Olomolaiye, 2017).
Financial Resource Characteristics.The study by Raes et al. (2020) proves a significant small and negative association between price and QoL domains of access to services, comfort and environment, food and meals, respect, and safety and security.
Occupancy rate contributes significantly and positively to personal attention dimension of QoL (Shippee, Henning-Smith, et al., 2015).On the other hand, there are facility characteristics with negative effects on QoL or FS.Medicaid status has a negative impact on personal attention and engagement dimension, as well as in the summary QoL (Shippee, Henning-Smith, et al., 2015) as well as in the environment dimension of FS (Shippee et al., 2017).
In relation to types of staff, the Hours Per Resident Day (HPRD) of Registered Nurses (RNs) and Certified Nurse Assistants (CNAs) have a positive effect on QoL (Abrahamson et al., 2013;Shippee, Hong, et al., 2015) and in some dimension of QoL: personal attention and food enjoyment in the study of Shippee, Hong, et al. (2015) for RNs, as well as spiritual WB in the study of Shin et al. (2014) for CNAs.HPRD of Licensed Social Workers (LSWs) also has a positive influence on personal attention, food enjoyment, and engagement (Shippee, Henning-Smith, et al., 2015).On the other hand, HPRD of Licensed Practical Nurses (LPNs) has a negative effect on the summary of QoL and on negative and positive mood.Furthermore, in the same way, administrative turnover in last year has a negative effect on negative and positive mood dimensions (Shippee, Henning-Smith, et al., 2015).
There are certain characteristics that have a negative influence on QoL, such as the turnover of RNs (Shin et al., 2014), with a negative influence in several dimensions of QoL, including dignity, meaningful activity, and security (Shin et al., 2014).Turnover of CNAs affects negatively on spiritual WB (Shin et al, 2014).Similarly, there are ratios with a negative effect, like the relationship between the amount of LPNs and the skill mix (ratio of more RNs to fewer LPNs and CNAs), the first (amount of LPNs) in the food enjoyment dimension, and the last (skill mix) in the meaningful activity, food enjoyment, and security dimensions (Shin et al., 2014).Finally, staff retention influences positively in the dimensions of FS: care, staff, and environment; but negatively in food dimension (Shippee et al., 2017).

Discussion
In this work we have carried out a systematic review of the literature of those studies that attempt to identify the characteristics of the facilities that influence or are related to QoL of the older adult residents.The main objective has been to obtain new evidence that can strengthen the determination of QoL through the characteristics of the facilities.

Summary of Characteristics of the Facilities Related to QoL
According to the results obtained, we can indicate that municipal and private facilities compared with charitable facilities, and government and non-profit facilities referenced to for-profit facilities obtain improvements in QoL or FS.Space identification, distance, and supporting facilities such as cognitive support, non-slip floor, furniture, recreation facilities, handrails, accessibility, doors and windows, and signage contribute significantly and positively to QoL.Similarly, ventilation and lighting, occupancy rates and the percentage of private rooms all contribute to improved QoL.In addition, in relation to staffing management, management hours, total hours of care, activity staffing, and HPRD of LSWs, RNs, CNAs, as well as staff retention contribute to QoL improvement.
On the other hand, facility price, Medicaid status, resident acuity, deficiencies, chain affiliation, size of the facility, water supply, attached to a hospital, HPRD of LPNs, administrative turnover, turnover of RNs, and turnover of CNAs obtains a negative relationship with QoL.The amount of LPNs HPRD, and ratio of more RNs to fewer LPNs and CNAs contribute to worsening of QoL.
Only the characteristics referred to ownership in reference to for profit, Medicaid status, resident acuity, distance, size of facility, recreation facilities, ventilation, rural location in reference to urban settings, activities staff, and HPRD of CNAs are included in at least two studies, but in most of them conducted by the same authors.Only the characteristics of rural location in reference to urban settings (Kehyayan et al, 2016;Shippee et al., 2017), activities staff (Abrahamson et al., 2013;Shippee, Henning-Smith, et al., 2015;Shippee, Hong, et al., 2015), and HPRD of CNAs (Abrahamson et al., 2013;Shin et al., 2014) are included in studies by different authors.
In the aforementioned studies there are no discrepancies regarding positive and negative contribution to QoL, except in the studies by Kehyayan et al. (2016) and Shippee et al. (2017), referring to settings located in rural areas compared to urban settings, with an improvement in the overall QoL in the first study and a worsening of FS in the second.These studies are carried out in Canada and Minnesota respectively.At this point it should be mentioned that there may be an important bias due to the scarcity of different locations in the studies, as only six countries are reflected, with Minnesota being reflected in four of the studies.

Comparative With Previous Studies
If the significant results obtained in the study by Xu et al. (2013) are contrasted with the present study, it can be seen that both agree that non-profit facilities have better QoL than for-profit facilities (Shippee et al., 2017).Both also agree that rural facilities improve QoL (Kehyayan et al., 2016).On the other hand, a higher percentage of private rooms, although it obtains an improvement in QoL, only does so in the negative mood dimension (Shippee, Henning-Smith, et al., 2015).In contrast, the study by Xu et al. (2013) indicates that HPRD of RNs has no significant relationship with QoL, but Shippee, Hong, et al. (2015) obtains a positive and significant relationship.
In relation to the results of Shin and Bae (2012), it did not clearly define the relationship between different levels of nursing staff skill mix and indicators of QoL.In the present study, management hours and total hours of care (Kehyayan et al., 2016), activity staff (Abrahamson et al., 2013;Shippee, Henning-Smith, et al., 2015;Shippee, Hong, et al., 2015), HPRD of RNs (Shippee, Hong, et al., 2015), and HPRD of CNAs (Abrahamson et al., 2013;Shin et al., 2014), as well as staff retention (Shippee et al., 2017) clearly contribute to better QoL or FS.On the other hand, HPRD of LPNs (Shippee, Henning-Smith, et al., 2015) and turnover of RNs (Shin et al., 2014) negatively contributes to QoL.

Differences Between Geographical Areas and Type of Facility
In this review, studies have been found in different countries and regions such as Hong Kong, Sweden, and Flanders, as well as in Canada and US, the latter where most of the studies have been found.It should be considered that each country has a different health care system, as well as different protection mechanisms for the older adults.The characteristics of the facilities may be different, with a greater or lesser impact on the residents.Only ownership and location has been studied in Long-term Care Facility and Medicaid-certified Nursing Homes (Kehyayan et al., 2016;Shippee et al., 2017), as well as HPRDs of CNAs in Nursing Homes and Medicaid-certified Nursing Homes (Abrahamson et al., 2013;Shin et al., 2014).
Broadly speaking, studies in the US and Canada have focused on Nursing Homes or Medicaid certified nursing homes, analyzing mainly structural characteristics, financial resources, and staffing.Studies outside North America, on the other hand, focus mainly on the relationship between characteristics related to space management, supporting facilities, and building services and the QoL of residents.We can consider that the results obtained should be limited to the type of facility and geographical area in which the outcomes have been obtained.

Concluding Remarks
Apart from the categories of staff-related, financial resource and structural, which are the most studied in the literature, more studies are generally needed on other characteristics related to the categories of space management, supporting facilities, and building services, as researchers have paid little attention.The construction of facilities should be planned, as well as the design of spaces and supporting facilities, since they could condition an improvement of QoL, as reflected in this study.This would contribute to a possible improvement of QoL from an early stage.Although the environment contributes to QoL, sometimes it is not possible to make decisions in this regard and, for example, location in rural or urban environments is necessary.Government decisions about ownership, chain affiliation, or Medicaid are often not intended to improve QoL, but these decisions may be necessary.On the other hand, staffing decisions influence the QoL and can be taken to improve it, but they cannot always be taken in that spirit, due to economic interests.
QoL domains based on the work of R. A. Kane et al. (2003), R. L. Kane et al. (2004) are confirmed as a good basis for its use in future works, although the interRAI Self-Report Nursing Home Quality of Life Survey or the WHOQOL Group (1998) definition are widely used.FS and psychological and social WB are also considered, with similar dimensions for the definition of QoL.

Limitations
The present study has several methodological limitations that should be acknowledged.Firstly, potential bias could have been present in the data extraction process, as it relied on the efforts of two authors.Secondly, the use of a narrative synthesis instead of a meta-analysis limited the ability to quantitatively synthesize the results.Furthermore, there is a possibility of publication bias as only published studies were included, potentially overlooking relevant unpublished research.It is important to note that the authors of the study acknowledged these limitations and made efforts to address them whenever possible.
This study also has limitations in terms of the scarcity of papers which analyze the relationship between facility characteristics and QoL in the last decade.It can be observed that the number of authors present in the results obtained is also scarce, that is, there are authors with several contributions.However, efforts have been made to address these limitations by incorporating and comparing the results with two previous reviews (Shin & Bae, 2012;Xu et al., 2013), thereby extending the temporal scope of the analysis.
In addition, the geographical scope is also limited, as there is little diversity of locations, highlighting that four of the studies have been carried out in Minnesota nursing homes.It can be stated that there are insufficient studies that allow comparison and delimitation of the characteristics of the facilities that reliably influence QoL.It is not always possible to extrapolate the results to other geographical areas or types of facilities, the protection systems for the older adults and their characteristics differ between countries.
One potential limitation of this study is the utilization of diverse measures of QoL across the included studies, which may hinder the comparability of findings.However, in order to address this limitation, the present study provides a clear rationale for the chosen measures and thoroughly discussing their strengths and limitations.This approach helps to mitigate the potential impact on comparability.
It is important to note that only facility characteristics demonstrating a significant relationship have been included in this study, which introduces the possibility of publication bias.It is possible that studies with significant findings are more likely to be published, while those with null findings may remain unpublished or unnoticed.
Furthermore, the inclusion of cross-sectional studies in this analysis poses a limitation in establishing causality between facility characteristics and QoL.Future research could incorporate longitudinal or experimental study designs, which allow for the examination of changes over time and provide stronger evidence for establishing causal relationships between facility characteristics and QoL.

Conclusions
In this review, in addition to extracting the main characteristics of the facilities that are related to QoL, the characteristics have been categorized into: Structural, Space Management, Supporting Facilities, Building Services, Financial Resources, and Staff-related.The main QoL measures used were extracted and related with facility's characteristics, finding that social and psychological WB, as well as FS are measures on comparable dimensions of QoL.Significant positive and negative relationships with QoL have been determined, in general terms.These relationships have been compared with previous reviews, indicating their correspondences and discrepancies, pointing out which characteristics should be focused on to find relationships with QoL in future studies.
From the analysis of 10 papers found in an extensive international bibliographic search in the last decade, we can conclude that there are few papers that relate the characteristics of the facility with QoL.More studies are needed to corroborate the findings of this review.This review has found that, in general, space management, supporting facilities, and building services categories have a positive relationship with QoL, as expected.Hours of management, care and activities, and hours of qualified staff affect positively to QoL.On the other hand, it is clear that charitable and for-profit facilities, Medicaid status, resident acuity, deficiencies, chain affiliation, and size, have a negative impact on QoL, as well as the financial resources (except occupancy rate) and HPRD of LPNs and turnover.
Further research is needed to study the relationship between QoL and the characteristics of space management, supporting facilities, and building services, in order to contribute to an improvement in QoL from the earliest stages of the conception of any type of facility.In addition, further studies on structural characteristics, financial resources, and staffing management are needed to support previous research in order to include new relationships with QoL.These studies should cover more geographical areas and corroborate their extension to other geographical areas and types of facilities.Finally, it can be considered that the work of R. A. Kane et al. (2003), R. L. Kane et al. (2004) is established as a good basis for the measuring of QoL, although other studies on WB and FS emerge as important contributors to QoL, and are used to associate the characteristics of the facilities with QoL.
This study highlights the need for more research on the relationship between facility characteristics and the QoL of older adult.While previous studies have explored this relationship, many of these studies have limitations such as small sample sizes, inconsistent measures of QoL, and a lack of consideration for important facility characteristics such as staffing levels and ownership status.This study aims to address these limitations and provide a more comprehensive understanding of the relationship between facility characteristics and QoL for older adult residents.In terms of social or academic influence, this study has important implications for healthcare policies and practices related to facilities for older adults.By identifying the facility characteristics that have a significant impact on QoL, this study can inform efforts to improve the quality of care and QoL for older adults in residential facilities.Additionally, this study contributes to the broader academic literature on aging and healthcare by providing a comprehensive review of previous research on this topic and highlighting areas for future research.
Studies on the influence of facility characteristics on the QoL of older adult residents have both social and academic influences.From a social perspective, these studies contribute to the improvement of care practices and policies in nursing homes and other residential facilities.By identifying the factors that affect the QoL of older adults, such as the physical environment, social interactions, and person-centered care approaches, these studies provide valuable insights for enhancing the wellbeing and satisfaction of residents.
Academically, these studies contribute to the body of knowledge in the field of gerontology and long-term care.They add to the existing literature by providing empirical evidence and a deeper understanding of the relationship between facility characteristics and QoL outcomes.This research helps to inform future research directions and guide the development of evidence-based interventions and practices in the field of older adults' care.
Furthermore, these studies can have broader societal implications, as they provide valuable information for policymakers, healthcare professionals, and facility administrators in their decision-making processes.Ultimately, the social and academic influence of these studies lies in their potential to improve the quality of care and QoL for older adults in residential settings, promoting better outcomes and experiences for this vulnerable population.
The findings of this study have important implications for healthcare providers, policymakers, and other stakeholders involved in the care of older adults in residential facilities.By prioritizing facility characteristics that promote QoL, these stakeholders can help to improve the overall well-being and satisfaction of older adult residents in these settings.This study can help managers and governors to improve the QoL of residents, with new perspectives associated with the characteristics of the facilities, with a direct implication for the improvement of the health care policy, so that governors can make decisions on the design of the facilities and their characteristics by means of regulatory frameworks to improve the QoL of residents from early stages.

Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Figure 1 .
Figure 1.Reporting items for systematic reviews and meta-analysis (PRISMA) flow chart.

Table 2 .
Summary of Studies Included in the Review.

Table 3 .
Summary of Facility Characteristics and Their Relationships With QoL.