Background: Frailty is highly prevalent in older people. Its serious adverse consequences, such as disability, are
considered to be a public health problem. Therefore, disability prevention in community-dwelling frail older people is
considered to be a priority for research and clinical practice in geriatric care. With regard to disability prevention, valid
screening instruments are needed to identify frail older people in time. The aim of this study was to evaluate and
compare the psychometric properties of three screening instruments: the Groningen Frailty Indicator (GFI), the Tilburg
Frailty Indicator (TFI) and the Sherbrooke Postal Questionnaire (SPQ). For validation purposes the Groningen Activity
Restriction Scale (GARS) was added.
Methods: A questionnaire was sent to 687 community-dwelling older people (≥ 70 years). Agreement between
instruments, internal consistency, and construct validity of instruments were evaluated and compared.
Results: The response rate was 77%. Prevalence estimates of frailty ranged from 40% to 59%. The highest agreement
was found between the GFI and the TFI (Cohen's kappa = 0.74). Cronbach's alpha for the GFI, the TFI and the SPQ was
0.73, 0.79 and 0.26, respectively. Scores on the three instruments correlated significantly with each other (GFI - TFI, r =
0.87; GFI - SPQ, r = 0.47; TFI - SPQ, r = 0.42) and with the GARS (GFI - GARS, r = 0.57; TFI - GARS, r = 0.61; SPQ - GARS, r =
0.46). The GFI and the TFI scores were, as expected, significantly related to age, sex, education and income.
Conclusions: The GFI and the TFI showed high internal consistency and construct validity in contrast to the SPQ. Based
on these findings it is not yet possible to conclude whether the GFI or the TFI should be preferred; data on the
predictive values of both instruments are needed. The SPQ seems less appropriate for postal screening of frailty among
community-dwelling older people.
CORE (COnnecting REpositories)
CORE (COnnecting REpositories)