With the increasing degree of aging, the proportion of functional decline in the elderly is increasing year by year. Early identification of functional decline is of great significance for realizing healthy aging. Delphi method has been used to construct and verify the function impairment screening tool (FIST) for the elderly.

To evaluate the feasibility, reliability and validity of the function impairment screening tool among community-dwelling older adults.

From March to August 2022, 145 elderly people aged 60 and above from different communities in Beijing were selected to evaluate the feasibility of the scale using the scale acceptance rate, scale qualification rate, and scale completion time; internal consistence reliability was evaluated using Cronbach's α and split-half reliability coefficients; construct validity was evaluated using exploratory factor analysis; and criterion validity was evaluated using Spearman's correlation analysis.

The FIST scale contains 3 dimensions with 16 items: ability of daily living (6 items), ability of domestic life (5 items), and ability of social activities (5 items). The FIST scale acceptance rate and scale qualification rate were both 100%, and the scale completion time was 1-2 min. The Cronbach's α for the FIST total scale was 0.924, and the Cronbach's α for the three dimensions of ability of daily living, ability of domestic life and ability of social activities were 0.588, 0.817 and 0.892. The corrected item-total correlation for the FIST corrected entries ranged from 0.058 to 0.898, and Cronbach's α after deleting an entry ranged from 0.910 to 0.928. The Spearman-Brown coefficient for the total FIST scale was 0.911 and the Guttman split-half coefficient was 0.709; the Spearman-Brown coefficients for the three dimensions of ability of daily living, ability of domestic life and ability of social activities were 0.703, 0.709 and 0.932, and the Guttman split-half coefficients were 0.646, 0.695 and 0.822. The exploratory factor analysis extracted four initial eigenvalues >1 male factors with a cumulative variance contribution of 78.61%, and the factor loadings for each entry ranged from 0.585 to 0.940. The Spearman rank correlation coefficient between the total score of the FIST scale and the Barthel index was 0.876 (P<0.001) .

FIST has high feasibility, reliability and validity and can be used as an assessment tool for physical function impairment in community-dwelling older adults.