The validity and reliability of a digital Ruff Figural Fluency Test (RFFT)

Background The Ruff Figural Fluency Test (RFFT) is a valid but time-consuming and labour-intensive cognitive paper-and-pencil test. A digital RFFT was developed that can be conducted independently using an iPad and Apple Pencil and RFFT scores are computed automatically. We investigated the validity and reliability of this digital RFFT. Methods We randomly allocated participants to the digital or paper-and-pencil RFFT. After the first test, the other test was performed immediately (cross-over). Participants were invited for a second digital RFFT 1 week later. For the digital RFFT, an (automatic) algorithm and two independent raters (criterion standard) assessed the number of unique designs (UD) and perseverative errors (PE). These raters also assessed the paper-and-pencil RFFT. We used Intraclass correlation coefficients (ICC), sensitivity, specificity, %-agreement, Kappa, and Bland–Altman plots. Results We included 94 participants (mean (SD) age 39.9 (14.8), 73.4% follow-up). Mean (SD) UD and median (IQR) PE of the digital RFFT were 84.2 (26.0) and 4 (2–7.3), respectively. Agreement between manual and automatic scoring of the digital RFFT was high for UD (ICC = 0.99, 95% CI 0.98, 0.99, sensitivity = 0.98; specificity = 0.96) and PE (ICC = 0.99, 95% CI 0.98, 0.99; sensitivity = 0.90, specificity = 1.00), indicating excellent criterion validity. Small but significant differences in UD were found between the automatic and manual scoring (mean difference: − 1.12, 95% CI − 1.92, − 0.33). Digital and paper-and-pencil RFFT had moderate agreement for UD (ICC = 0.73, 95% CI 0.34, 0.87) and poor agreement for PE (ICC = 0.47, 95% CI 0.30, 0.62). Participants had fewer UD on the digital than paper-and-pencil RFFT (mean difference: − 7.09, 95% CI − 11.80, − 2.38). The number of UD on the digital RFFT was associated with higher education (Spearman’s r = 0.43, p < 0.001), and younger age (Pearson’s r = − 0.36, p < 0.001), showing its ability to discriminate between different age categories and levels of education. Test–retest reliability was moderate (ICC = 0.74, 95% CI 0.61, 0.83). Conclusions The automatic scoring of the digital RFFT has good criterion and convergent validity. There was low agreement between the digital RFFT and paper-and-pencil RFFT and moderate test–retest reliability, which can be explained by learning effects. The digital RFFT is a valid and reliable instrument to measure executive cognitive function among the general population and is a feasible alternative to the paper-and-pencil RFFT in large-scale studies. However, its scores cannot be used interchangeably with the paper-and-pencil RFFT scores.

TREATABLE VASCULAR RISK AND COGNITIVE PERFORMANCE IN PERSONS AGED 35 YEARS OR OLDER: LONGITUDINAL STUDY OF SIX YEARS

Background: Poor cognitive performance is associated with high vascular risk. However, this association is only investigated in elderly. As neuropathological changes precede clinical symptoms of cognitive impairment by several decades, it is likely that cognitive performance is already associated with vascular risk at middle-age. OBJECTIVES: To investigate the association of cognitive performance with treatable vascular risk in middle-aged and old persons. DESIGN: Longitudinal study with three measurements during follow-up period of 5.5 years. SETTING: City of Groningen, the Netherlands. PARTICIPANTS: Cohort of 3,572 participants (age range, 35-82 years; mean age, 54 years; men, 52%). EXPOSURE: Treatable vascular risk as defined by treatable components of the Framingham Risk Score for Cardiovascular Disease at the first measurement (diabetes mellitus, smoking, hypercholesterolemia and hypertension). MEASUREMENTS: Change in cognitive performance during follow-up. Cognitive performance was measured with Ruff Figural Fluency Test (RFFT) and Visual Association Test (VAT), and calculated as the average of the standardized RFFT and VAT score per participant. RESULTS: The mean (SD) cognitive performance changed from 0.00 (0.79) at the first measurement to 0.15 (0.83) at second measurement and to 0.39 (0.82) at the third measurement (Ptrend<0.001). This change was negatively associated with treatable vascular risk: the change in cognitive performance between two measurements decreased with 0.004 per one-point increment of treatable vascular risk (95%CI, -0.008 to 0.000; P=0.05) and with 0.006 per one-year increment of age (95%CI, -0.008 to -0.004; P<0.001). CONCLUSIONS: Change in cognitive performance was associated with treatable vascular risk in persons aged 35 years or older.

Cognitive engagement profile of the fluency tasks performance by patients with schizophrenia

IntroductionFluency tasks, e.g. verbal, design fluency test, etc. are often used in the evaluation of cognitive function in patients with schizophrenia. In the standard approach, the test result is the sum of stimuli generated in a given time period. However, this approach does not allow to determinate of what strategies are used by subjects to regulate the cognitive engagement during task execution.AimTo investigate the specific dynamic profile of fluency tests performance comparing with healthy controls.MethodsThirty patients diagnosed with schizophrenia and 30 demographically matched healthy controls took part in the study. Participants performed two tests: COWAT (3 trials) and Ruff Figural Fluency Test in accordance with the original instructions. During the generation of these stimuli, the investigator wrote down their quantity in 15-second intervals, which enables the assessment of cognitive engagement variability in different parts of the whole time (1 minute).ResultsComparison of cognitive engagement variation in both fluency tests showed statistically significant differences. The differences in repeated measures ANOVA with group as an independent variables reached P < 0.0001. Factor differentiating the profiles in verbal and figural fluency was first 15 seconds after the tasks started.ConclusionsThe beginning of task was the most difficult part for patients with schizophrenia, which may indicate that the overall worse performance of fluency tests is associated with significant difficulties in mobilizing the cognitive activity.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Validity and Reliability of the Polish Adaptation of the Ruff Figural Fluency Test

Normative studies of the Polish adaptation of Th e Ruff Figural Fluency Test (RFFT) were conducted on 475 men and women aged 16-79, taking into consideration such factors as gender, education, and place of residence. Clinical studies were also performed on a group of patients with left -, right-, or bilateral hemispheric brain lesions, Parkinson’s disease, Huntingon’s disease, progressive obturational lung disease, dementia and depression. Th e results support the utility of the RFFT as a measure of executive functions. Th e validity and reliability indices of the Polish version of the test are similar to those reported by Ruff (1996). However, the sample Polish test performance differs notably from American samples performance and this difference is discussed.