ReviewChallenges and strategies pertaining to recruitment and retention of frail elderly in research studies: A systematic review
Introduction
The term “frail older adults” refers to a population with reduced reserves and resistance to stressors, and thus at increased risk of falls, disability, hospitalization and institutionalization (Fried et al., 2001). Based on recent studies, they represent 7–23% of community-dwelling older adults (Song et al., 2010, Syddall et al., 2010) and this proportion is likely to increase as the population ages (Collard, Boter, Schoevers, & Oude Voshaar, 2012). Frail elders account for a large proportion of patients enrolled in rehabilitation programs (Wells, Seabrook, Stolee, Borrie, & Knoefel, 2003) and are major consumers of home care services (Rochat et al., 2010). Despite their growing numbers, little is known about the complex needs of this population (Rockwood & Mitnitski, 2011). This lack of knowledge could lead to providing inappropriate health care services to vulnerable older people (Bergman et al., 2007).
Although more research is needed with this population, recruitment and retention of frail elderly in research studies represents a challenge. Some studies have reported lower rates of enrollment and higher drop-out rates in this group (Chatfield et al., 2005, Harris and Dyson, 2001), especially in longitudinal studies on health and function (Kempen & van Sonderen, 2002). This could lead to misrepresentation of frail older adults in research studies and, ultimately, to erroneous conclusions about the effects of interventions on them (Barry, 2005). On one hand, since frail older adults are at a higher risk of adverse outcomes, interventions may not be as effective for them and may even produce worse side effects (Bergman et al., 2007, Ferrucci et al., 2003). For example, due to their vulnerability, frail older adults may have more difficulty coping with the consequences of surgery following a hip fracture than non-frail older adults (Menzies, Mendelson, Kates, & Friedman, 2012). More specifically, in this population, prolonged hospitalization is more likely to lead to deconditioning (Dasgupta, Rolfson, Stolee, Borrie, & Speechley, 2009) and anesthesia is more likely to trigger cognitive impairments (delirium) (Leung, Tsai, & Sands, 2011). On the other hand, since even minor changes may have a huge impact on their functional outcomes, small improvements may be clinically significant (Gitlin et al., 2008, Lally and Crome, 2007). For example, it is expected that some interventions (e.g., nutrition or exercise programs, extended rehabilitation, and environmental home modifications tailed to their specific needs) may lead to modest improvements of their function or autonomy (Kelaiditi et al., 2014, Theou et al., 2011, Wells et al., 2003), which can be sufficient to enable them remain at home (Mann et al., 1999, Ryburn et al., 2009). It is thus important to know how to adapt existing interventions to minimize complications and to measure the real impact of preventative disability programs in this population. However, such knowledge cannot be generalized to older frail individuals unless this subpopulation is included in these studies.
In research with older adults, frailty may contribute to increased rates of refusal or drop-out (Kempen & van Sonderen, 2002). However, little is known about the barriers to participation that pertain specifically to this subpopulation. Since frailty is a complex multidimensional condition (Gobbens et al., 2010, Rockwood and Mitnitski, 2011), many factors could adversely affect their participation in research. For example, physical (e.g., decreased gate speed, fatigue) and psychosocial factors (e.g., decreased attention, living alone) may increase respondent burden and pose methodological challenges in terms of measure selection and transportation (Ferrucci et al., 2004, McNeely and Clements, 1994). There is thus a need to know more about the specific factors that impede participation of frail older adults in research, which will be useful to design effective recruitment and retention strategies.
Thus, it is important to identify challenges that may prevent participation of frail older adults in research studies, especially those pertaining to interventions preventing adverse outcomes such as falls, disability, (re) hospitalization or institutionalization (e.g., changes in environment, organization of services, case management, exercise program, surgery, nutritional supplementation) (Ferrucci et al., 2004). Improving recruitment and retention among the frail elderly will help to determine if results from studies conducted with older adults may apply to this specific population. To the best of our knowledge, no previous study systematically reviewed the challenges encountered and the strategies used specifically with frail older adults. Therefore, the aim of this systematic review was to identify the type and the impact of challenges and strategies pertaining to recruitment and retention of frail elderly in research studies.
Section snippets
Search strategy
The methods used for this systematic review were based on a standardized protocol that was described by Pai et al. (2004).
Literature searches were performed in four databases (Medline, CINALH, Ageline, Embase). As there is no widely accepted definition of frailty in the literature, a broader search including related concepts (i.e., vulnerable, homebound) was conducted. For each database, a core set of medical subject headings was identified (cf. Appendix A). To capture any further relevant
Results
The electronic search strategy yielded 916 potentially relevant articles. Screening of the titles and abstracts identified 33 full-text publications for further review. A manual search of the reference lists of selected articles resulted in one additional study. Fifteen of the 34 met all the inclusion criteria and were retained for assessment of their level of evidence and data abstraction (see Fig. 1).
Table 1 presents the relevance, the methodological quality and the main characteristics of
Discussion
Underrepresentation of frail individuals in research studies about interventions preventing falls, disability, hospitalization and institutionalization may lead to inaccurate conclusions about either their negative impact (unexpected adverse outcomes) or positive effect (unrecognized benefits). Thus, it is important to know more about the specific factors that impede participation of frail older adults in research, and to identify ways to increase their inclusion in research studies. This study
Conclusion
The review highlights the need to improve knowledge about the impact of barriers and strategies on recruitment and retention of a well-defined frail population, based on validated frailty criteria. A better understanding of the challenges and the ways to improve the recruitment and retention of frail older adults in research studies should lead to a better representation of this subpopulation in larger studies on aging. We thus emphasize the need for more transparency in research by providing
Conflict of interest statement
None.
Funding sources
The authors gratefully acknowledge the financial support provided by the Centre de recherche sur le vieillissement de Québec. Personal financial support for Dr. Mortenson was provided by a Banting postdoctoral fellowship. The sponsors did not have any role on the conduct, analysis or reporting of the study.
References (56)
- et al.
Recruiting older adults for clinical trials
Controlled Clinical Trials
(1997) - et al.
A systematic literature review of attrition between waves in longitudinal studies in the elderly shows a consistent pattern of dropout between differing studies
Journal of Clinical Epidemiology
(2005) - et al.
Frailty is associated with postoperative complications in older adults with medical problems
Archives of Gerontology and Geriatrics
(2009) - et al.
The frailty syndrome: A critical issue in geriatric oncology
Critical Reviews in Oncology/Hematology
(2003) - et al.
Determinants of frailty
Journal of the American Medical Directors Association
(2010) - et al.
Effective recruitment of minority populations through community-led strategies
American Journal of Preventive Medicine
(2009) - et al.
Psychological attributes and changes in disability among low-functioning older persons: Does attrition affect the outcomes?
Journal of Clinical Epidemiology
(2002) - et al.
Frailty defined by deficit accumulation and geriatric medicine defined by frailty
Clinics in Geriatric Medicine
(2011) - et al.
How should we grade frailty in 15 nursing home patients?
Journal of the American Medical Directors Association
(2007) - et al.
State of the art in geriatric rehabilitation. Part I: Review of frailty and comprehensive geriatric assessment
Archives of Physical Medicine and Rehabilitation
(2003)
A randomized, controlled trial of disability prevention in frail older patients screened in primary care: The FRASI Study. Design and baseline evaluation
Aging Clinical and Experimental Research
Detecting and categorizing frailty status in older adults using a self-report screening instrument
Archives of Gerontology and Geriatrics
How attrition impacts the internal and external validity of longitudinal research
Journal of School Health
Frailty: An emerging research and clinical paradigm—Issues and controversies
Journal of Gerontology: Medical Sciences
Prevalence of frailty in community-dwelling older persons: A systematic review
Journal of the American Geriatrics Society
An innovative approach to recruiting homebound older adults
Research in Gerontological Nursing
Recruitment of rural community-dwelling older adults: Barriers, challenges and strategies
Aging and Mental Health
Internet, mail, and mixed-mode surveys: The tailored design method
The feasibility of creating a checklist for the assessment of the methodological quality both of randomized and non-randomized studies of health care interventions
Journal of Epidemiology and Community Health
Identifying frailty: Do the Frailty Index and Groningen Frailty Indicator cover different clinical perspectives? A cross-sectional study
BMC Family Practice
Subject recruitment, retention and protocol feasibility in a prospective study of nutritional risk among urban, frail homebound elders
Journal of Nutrition for the Elderly
Designing randomized, controlled trials aimed at preventing or delaying functional decline and disability in frail, older persons: A consensus report
Journal of the American Geriatrics Society
Frailty and failure to thrive
Frailty in older adults: Evidence for a phenotype
Journals of Gerontology. Series A: Biological Sciences and Medical Sciences
Psychological well-being and incident frailty in men and women: The English Longitudinal Study of Ageing
Psychological Medicine
Gaining and sustaining minority participation in longitudinal research projects
Alzheimer Disease and Associated Disorders
Two recruitment strategies for a clinical trial of physically frail community-living older persons
Journal of the American Geriatrics Society
Variation in response to a home intervention to support daily function by age, race, sex, and education
Journals of Gerontology. Series A: Biological Sciences and Medical Sciences
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