Dovepress the words “key,” “toothbrush,” and “lamp” were used, and the subjects were informed that they would be asked to recall the words later. A score of 0 was used to define the case group with cognitive impairment. Measurement of depressive illness Depressive illness was assessed using the Montgomery– Asberg Depression Rating Scale,22 a subscale of the Comprehensive Psychiatric Rating Scale.26 Nine questions and one observational item cover the symptoms of the DSM-IV criteria27 for depressive disorder. Symptoms and signs were rated on a scale ranging from 0 to 6 points, with a maximum score of 60. A mean score of 20 or less was defined as no severe depressive illness.28 Measurement of physical function Timed Up and Go The Timed Up and Go (TUG) test measures the time (in seconds) it takes to rise from a chair, walk 3 m, turn, walk back, and sit down again.29 A chair with armrests and a seat height of 45 cm were used, and the time from leaving the seat until seated again was measured. The subjects were allowed to rise using their preferred method. High test–retest30 and intra- and inter-rater reliability29 have been demonstrated for this test in older people, and the results show correlation with the Berg Balance Scale (r = -0.81) and self-selected walking speed (r = -0.61).29 Walking 15 m and 2 × 15 m, including a 180° turn From a 2 m flying start, the subjects were instructed to walk 15 m, turn at a marker, and return to and pass the starting point before stopping. The time was recorded for the first 15 m and 2 × 15 m for both self-selected and fast speeds. The walking speed (WS) was calculated (m/s), using the time for the first 15 m. Measures of WS at both self-selected and high speeds have been found to be highly reliable (intraclass correlation [ICC] $  0.903) and significantly correlated with muscle strength in the lower extremities.31 The 2 × 15 m walking test is a more complex test, which includes both a longer walk- ing distance and a provocation of balance. The reliability of the 2 × 15 m walking test at both speeds has been shown to be very high in elderly women (ICC 0.95–0.98). The results also correlated with balance tests, such as one-leg standing (OLS) and tandem stance (r = 0.39–0.64).32 Step test Subjects were placed in front of a block 7.5 cm high, positioned stably against a wall. The subjects stood, with feet parallel, Clinical Interventions in Aging 2012:7 Cognitive impairment associated with slower physical test results at a marked distance of 5 cm from the block. They were asked to place one foot entirely on the block and then return it to the floor, repeatedly, as quickly as possible. Subjects were unsupported, but the examiner stood close by for safety. The total number of steps completed during 15 seconds was recorded, first for the right and then for the left leg.33 The best value from two tests of each leg was used in the analysis. The test has been shown to be reliable (ICC . 0.90) and to correlate with self-selected walking speed.33 Chair stands Subjects were asked to rise from a chair, five times, as quickly as possible, with their arms folded and their hands on their shoulders. The chair had no armrests, and the height of the seat was 45 cm. Subjects were instructed to stand up completely between repetitions. Before the test, the subjects were asked to rise without using their hands, to ensure that the procedure was safe. The test was performed once, and the time required to complete five stands was recorded. High reli- ability coefficients have been reported (r = 0.80; ICC = 0.89, 95% confidence interval [CI] = 0.79, 0.95).34,35 Performance is associated with muscle strength and balance, as well as sensorimotor and psychological factors.36 One-leg standing – eyes open With their eyes open and their arms loosely hanging, the subjects were asked to stand first on the right leg and then on the left leg, for as long as possible. The raised leg was flexed at the knee joint, with the foot well off the floor. Timing began when the subject lifted the foot. For safety, the examiner stood close to the subject throughout the tests. The clock was stopped when the subject touched the floor with the raised foot, changed the position of the supporting foot, or after 60 seconds had elapsed. Subjects were barefoot during the test, and a trial was carried out before testing. The best result of two tests was used in the analysis. Performance was categorized into four categories: ,10 seconds, ,20 seconds, ,30 seconds, and $30 seconds. The reliability has been shown to be moderate (r = 0.69),34 to high (ICC = 0.93–0.99)37 in middle-aged and older people. Procedures of measurements of physical function Each subject was given verbal instructions and a demonstra- tion of each test. Each subject was tested on a single occasion, and the tests were carried out in the following order: OLS, step test, chair stands, TUG, and walking 2 × 15 m. Subjects wore their ordinary shoes, except in the OLS test. A standard submit your manuscript | www.dovepress.com Dovepress 197